What's the max temp for continuous use in the Alli?

[chuntag95]

It's starting to get a bit warm down here. We are hitting 95 most days and my Allison is hitting 200 on most of them. I have the Fred Scoop installed and that has kept it out of the 220 range, but I can still hit 200 easy. Is this a problem long term? :confused: Am I being overly cautious? redface.gif What do you think about adding a second cooler or a temperature controlled fan on the existing one? I kinda like the second option because the keeps me from not warming up in the winter. I have heard figures of 90% of all tranny failures are heat related. Also, I read that temps over 180 are reducing the lifetime. :eek: Who had done something other than the scoop?

[mackin]

I find when it is Hot it will easily match engine temp .... Allison says max temp 225...

I have a chart (on my other computer)that states tranny temp and life ... Ultimately anything above 175 shortens life two fold ...

I would switch to Tranysnd and or a synthetic of choice and add a deep pan for added capacity all be it only two quarts ...

But the choice is yours,some feel it's no big deal ...Me I would considering you only have a 36K warranty then your on your own ...

If your a power adder even so ....

Mac

[chuntag95]

Mac,
I already have the transynd, but didn't go with the deep pan. Looks like that might be in my future. Did you see a temp differnce when you put the deep pan on?
Chris

[GM Smitty]

Chris - It's been pretty warm here too. My tranny temps have been hovering around the 190-200 mark driving around town and I was thinking it was a bit warm for my taste also.
I also have the Fred scoop. I didn't see much of a difference in temps since switching to the deep pan and Transynd either. Using tow/haul helps a bit to drop temps. I can't see the scoop making a difference around town, but on the highway, the temp seems to drop about 10 degrees or so once I get moving.
It's real tight in the front of the tranny cooler....a fan would have to be awfully thin to fit. I started to look into it, but then we got into fall and my tranny temps fell with the cooler weather. Haven't thought about it since.
Josh

[DalDMax]

Chris,
Anything to take your mind off of the filter issue huh :D
Has anyone given thought to applying heatsinks to the bottom of the OEM trans oil pan to remove heat?
I haven't seen my trans temp go quite that high yet, and I get into a little traffic every evening leaving the downtown Dallas area. Something different in the 03s?

Adam

[chuntag95]

I found one at Summit Racing that is only 2.25" thick and 7.25 in diameter. I measured and it will fit behind the cooler in front of the radiator. The fan plus a thermal swithc will be about a C note. At this point, that's not much to keep a $6K tranny alive longer. I have had some slipping and strange stuff when she get's hot. I don't know if I believe the gauges on this thing or not. The oil pressure and tranny temp just make me wonder, you know? :confused: I guess I need to order some more parts. Boy, my wife's going to kill me if she ever finds the bill. :D

[mackin]

=>At degrees Life Expectancey conventional erl ....
175 240,000
195 120,000
220 50,000
240 25,000
260 15,000
295 4,000

Mine when ambient temps in the 90's and humid match the operating temp ..... Rarely idling it will reach a deuce or better ... But come down to match operating temp once on the move .... I use tow haul constant in stop and go .... I really seen no drop in temp with deep pan and synthetic, that I can recall, has been a long long time since I switched ... But that is irrelevant to quality of fluid with synthetic have higher break down temp in viscosity index resulting in less wear .... More capacity speaks for itself .....To each there own, but I want what is best ..... All heavy service Allison's come deep paned Transynd ......

Mac

=> These are average prices I have gotten them localy cheaper at Detroit Allison .....Right Tony ... ;)

=> Pan: 29536522 $48.87
Gasket, not needed : 29536526 $29.36
Filter-Suction, Deep: 29537966 $21.22
Spin on filter: 29537268 $8.87

Trynsnd 5 gallon pail $128 bucks ...Let me know if it can be beat ...... ;)

[ 06-26-2003, 07:17 PM: Message edited by: mackin ]

[DalDMax]

Chris,
Is the temp lower when moving than when in stop and go by very much? Have you looked for a HD/Severe duty fan clutch for the DMax? Just thinking that if you are going to spend money to move more air, why not upgrade the main cooling fan?

[DalDMax]

Something else.. I haven't had time to check but...on most all other trucks I've seen the trans oil goes through the radiator as well as the aux trans oil cooler to help warm the trans oil when it is cold. If this is the case on the DMax as well, and you get the trans oil nice and cool,and then it is pushed through the radiator which is hotter.......

[chuntag95]

I usually see around 150-160 if I stay moving. It's the stop and wait for the @!#%*& traffic, DART Rail, trains, and old and ugly that I get stuck behind. If I get on the highway and go for a while after getting up in temps, I'll get down to 190 or maybe 180 best case. I ordered the fan and temp controller. I don't want to defeat the warmup side, but I also don't want to cook it in traffic. I'll play guinea pig on the fan and see how it does. The second thought I had was an inline thermostat that would open up a second cooler when it hit 180 or so. They have them for oil, so the line is big enough for the Alli. Just can't leave well enough alone, but the temps have bothered me for a while now.

I keep saying _______ is my last project for a while. :rolleyes: I can say the fuel filters and lift pumps are a done deal. Went almost an entire tank without catch any air in my little sight glass. I didn't have to bleed at all when I filled up last night. :D

Back on topic - I orderd the fan and the adjustable temperature controller and they are due in week after next. The question is push vs. pull, but I think I will do pull since I have the scoop already. I have not looked into a HD fan clutch as I would HOPE the general put one on to begin with. It is a 3/4 Ton HD truck. :rolleyes:

As far as 03 vs. 01 and 02, the front grill is different and there is a more direct air flow into the tranny cooler (as I understand it). That was the whole scoop idea. The scoop gained s few degrees, but only enough to keep me from panic. At least the tranny hasn't had anymore funny shifts since I got the scoop and I have not hit 220 again either. Being an enginerd like I am, my thinking is why get 20 degrees cooler when 40 will do. :D

Modify On!

[DalDMax]

Chris,
I was installing the JK Headlight harness on my truck this weekend and while I had things apart, I noticed that there appears to be room for a much larger trans cooler.
If you doubled the size of the trans cooler wouldn't that achieve the desired effect without another electro-mechanical device to fail?

Of course the more heat you disperse in front of the evaporator, the intercooler and radiator the harder those have to work......

[a64pilot]

Chris,
Have you verified your temp? I noticed on another post you had one of those fancy infra-red thermometers. If your actual temps are what the gauge shows it sounds like your tranny has a problem. Your truck is still under warranty isn't it?
A lot of people are driving in the same conditions you are with much higher gross weights and have lower tranny temps. Maybe you should try getting the dealer a chance to replace it while it is still stock and under warranty.

[pinehill]

Quite a while back, several people here (mdrag & SoCalDmax?) installed high quality auxilliary tranny temp. probes and guages. As I recall, the tranny fluid temps as measured by these add-ons were about 20* lower than what the cheesy OEM guages showed.

[pinehill]

Quite a while back, several people here (mdrag & SoCalDmax?) installed high quality auxilliary tranny temp. probes and guages. As I recall, the tranny fluid temps as measured by these add-ons were about 20* lower than what the cheesy OEM guages showed.

[chuntag95]

DalDMax,
My concern with just adding another cooler is the winter. I want it to reach operating temp eventually. I did consider an inline temperature control valve that would open up to the second cooler at 180 degrees. Still thinking on the best way to go, but the fan can be removed easily.
a64,
Yes, I am under warranty and I did take it in about being hot last year. They couldn't find anything. It wouldn't shift into OD the otherday, so it probably needs to go back and get checked. I might do that next week before our vacation. I can hit it with the laser to verify, but I don't know where the temperature sensor is relative to the cooler. Taking the temp at a different spot than the probe won't tell me much. I was going to use that method to determine what temp I need to set the controller at. The fan and controller should be here tomorrow and Thursday.

[fred]

hi, ive seen 95 deg temps here too, i working on a liquid add on for the cooler this week ,i get back if it works any better,it would work for short periods of time like when towing up a hill,but we"ll see

thanks,fred

[dmaxalliTech]

Chuntag:

I can hit it with the laser to verify, but I don't know where the temperature sensor is relative to the cooler The temp sensor is part of the pressure manifold switch inside the trans and bolts directly to valve body.

Mackin:

Pan: 29536522 $48.87
Gasket, not needed : 29536526 $29.36
Filter-Suction, Deep: 29537966 $21.22
Spin on filter: 29537268 $8.87

Trynsnd 5 gallon pail $128 bucks ...Let me know if it can be beat ...... Mac, those are good prices, but to answer your q.
Pan, yes
filter, yes
spin, yes
transynd bucket, no
gasket, who cares

[chuntag95]

dmaxalli Tech,
Thanks. Now I know that the temps are not going to mesh. I need to break down and put in another SPA(s) for Tranny temp and oil temp and oil pressure. I'm not a fan of the accuracy of the OEM gauges, but at least I know I am consistant. I wonder if the 210 I hit yesterday is really that high and if I am cooking the tranny sloowwwwlllyyy. Almost better when you don't know sometimes, you know? :rolleyes:
Fred,
What do you have in mind?

Chris

[BigO]

Just got back from vacation towing 9,300 lbs, 5th wheel. Pulled from Los Angeles,CA to Phx, AZ in 111 - 116 degrees based on built in temp gauge. The trany temp gauge ran right at 200 degrees or 195 all the way, (running 70 MPH) stock tranny fluid. Will be changing to Tranysnd at 20,000 miles.

[chuntag95]

Dropped her off this morning to get the tranny looked at. Told them about the time it would not shift into OD. Told them about the hard shifting and told them about the slipping when the fluid gets to the 210 range. I'm talking slipping to the point of being afaid you have lost the tranny. The response I got was how bullet proof these Allisons are. Bullets are not the problem, :mad: heat is. I can just imagine what would happen if I actually towed heavy with it. :eek: I guess my truck just doesn't like city living. :rolleyes: I run Transynd, change my spin on at every oil change, watch my temps and don't abuse my truck. There is no reason for this tranny to run 210. The fluid also didn't look or smell so good. It wasn't burnt, but it wasn't sweet smelling either. I might go to Mobil or Amsoil transmission fluid. I'm glad I got the extended warranty to 75K and 5 years. I hope I don't need it.

[a bear]

Chris,
Is the heat causing the slippin or is the slipping causing the heat ?

[chuntag95]

Tommy,

I think the only time it has slipped, it has been hot, but am not 100%. I can't really say one way or the other, but if it slipped and wasn't hot, that would explain why sometimes it get's hot and others it's just fine. Maybe they will find out something, but at least I got it on record that it is having problems. It was getting hot last year and I took it in, so this is twice now. I really love my truck, but it scares me that I might end up on the side of the road next week on my way to KC. If it was just me, no biggy, but I'll have the wife and kids, and them, I don't mess around.

Where did you get your temp gauge and probe that you used on the fuel? Would it fit down the tranny dipstick tube? I could check the temp that way and see how close or far off the gauge is, but then again it slipped, so the temp isn't the bottom line issue here either.

[a bear]

Just a cheap-o from walmart but very accurate. One of those indoor/outdoor types. The one I use only goes up to 160 degrees though.

[chuntag95]

Nuts. Anything that has a high enough temp doesn't have a long enough probe. Maybe I will sacrafice the one I have at home to try and get a reading before it get's too hot.

[ChevysRus]

Looked into adding a second cooler for the tranny a while back, but deep pan solved the heat problem.

Was going to add a second cooler with a lever type valve to shut off the In Line flow in winter to bypass the second cooler and turn it on again in summer. Problem was our stock cooler has large, very large "coronary" and have not found similar aftermarket cooler that could give same flow rates. Don't need another pressure point in the system and starve the Tranny of full flow capacity. Could just get a stock second cooler I suppose.

Maybe if something "big" comes out, will consider it again. Was going to mount it underneath and add a louvered shield. Anyway never gets over 200 even when towing in 100 degree ambients since adding deep pan and changing Transynd twice in 30K. Maybe your Transynd is still mixed with a little Dex. Think about changing again to get 99.9% pure Transynd. Might make a difference depending on how you made the first changeover and how much of the DEX you got rid of.

Second stock cooler "stacked" with a cutoff valve might be just the ticket now that I am thinking about it again.

Good Luck

[chuntag95]

I had not thought of just using a valve to control summer vs. winter. I was going to use a factory cooler due to the large diameter. I did find some race car oil coolers that were large enough, but in the same price range as an OEM. I am going to do the deep pan and change the fluid when I get back from Vacation. I leave Saturday and would like to do it before, but don't see anyway to get the parts or find that time. Highway should be okay.

Mac, did you see any difference between the Transynd and the Mobil ATF? I think it was you that changed it out.

The update from the stealer was they could not reproduce anything. No getting hot, no slipping and it always shifted fine. At least I have it on record.

[DalDMax]

Chris,
Did you give up on a cooling fan?
How many more quarts will the deep pan hold over the OEM pan?

[chuntag95]

DalDMax,

Give up? Me? NEVER! :D I am planning on looking at it tonight when I get it from the stealer. I think I will have to adjust the mounting to get everything to work. I'll just have to see how hard that will be to do.

The advantage to the second cooler, either controlled with a thermostat bypass valve or a manual valve, would be no electrical noise. Between cell phones, CB, radio, Satellite radio (in route) I don't need any more noise. Any solution will have to be easy on me. I will over design to avoid working too much, which usually ends up being more work. ;)

IIRC, someone correct me if I am wrong, the deep pan adds 3-3.5 quarts to the capacity. I used 4 gallons for my flush with the OEM and it is recommended to use 5 when adding the deep pan.

You know, if GM would just design them like me, I could save a bunch of work and money.m :rolleyes:

[Lone Eagle]

chuntag95, I seem to remember that the people that make after market coolers have the solenoid kits to bypass the coolers in winter. Later! Lone Eagle ;)

[ratlover]

Originally posted by chuntag95:
You know, if GM would just design them like me, I could save a bunch of work and money.m :rolleyes: If GM had you as a part of thier design team the price would be in Porshe country :eek: tongue.gif

It would be cool(albeit overkill to the gills) but I could never afford it :(

[chuntag95]

I have found a bypass valve that is temperature controlled. The only problem is it's at 185 +/- 10. I would be fine with the minus 10, not the plus. Anyhoo,

I installed the fan last night. My temp controller had to be mounted within a foot or so of the cooler due to the very short wire on the probe. The probe was 1/4" diameter, better known as HUGE when sticking it inbetween fins. At 170 on the factory temp it did not turn on this morning. I have not got the manual switch installed as of yet. I need to adjust the temp down if possible. Some interesting issues were the grill center post being in the way. I offset the fan to the right looking at the cooler. I think that would be the cooler side, so I put the probe on the other. Had to mount it in the push mode as I didn't take time to make new brakets and cut off the old ones to mount behind the cooler. There is room to get a larger cooler in there, so that might be a different option. It was a pain trying to get the scoop, fan and grill to all fit correctly. I need to take some more pictures as the first ones were when I couldn't get the grill on. redface.gif I also need to get the thermostat control working at a good temp. I can go down from the factory preset of 160 to 150. Don't know what that translates to on the factory gauge. I'll keep you informed.

[chuntag95]

The saga continues. I could not get the fan to turn on with the temp prob in the cooler. I decided to "test" it and put a lighter under it. It would finally kick on, but I couldn't get a temp. I used my laser to check temps and it was showing over 150 for the incoming line. I tie wrapped the probe to the line and covered with insulation. I should know this afternoon it it's going to work. If it doesn't, then we go with the low tech switch in the cab, which I am thinking about doing anyway.

[chuntag95]

Originally posted by ratlover:
If GM had you as a part of thier design team the price would be in Porshe country :eek: tongue.gif

It would be cool(albeit overkill to the gills) but I could never afford it :( [/QUOTE]

Sure you would! Porsche is the number 1 maker with the fewest breakdowns per J.D. Powers, so you would only have to buy one and it would last forever. :eek: I have a bunch more mods to catch up to Porsche money. :D I have a friend that has 2 Porsches and he is always messing with them like we do our trucks. You should see his parts bills. :rolleyes: If mods are in your blood, you can own a Yugo and tinker all the time.

[chuntag95]

Had a bad night for projects last night. Hosed up the fan blade when I realized I forgot to turn it over to make it a pusher. The thing stripped out and I couldn't get the nut off. :mad: I finally ripped it off and mangled it quite nicely. I used JB Weld to reconstruct it, but it's a little off center and out of balance. :eek: I sent a message to Derale asking if I could get a new blade. In frustration (when the rain started) I pulled the fuse and put the front back on. I did get the thermostat control working. The instructions were backwards on the controls. You go clockwise to lower the start temp, not counter. :rolleyes:

Question, since I have it off now, what side is better to mount the fan? I had it on the out, but am thinking the in would be better since you would have a higher delta temp on that side. A64? Bill? Tommy? John? Hoot? Mdrag? Mac? Etc.?

I think I am going to put a switch that will force it on and have a position to shut it off completely. Normal will be to run only when the engine is on and if you shut down, it shuts off with it.

Going on vacation tomorrow, so I hope I get time to finish this before I leave. If not, then next week.

[DalDMax]

Is the thermostat built into the fan unit?
The thermostat should definitely be behind the cooler. Of course it would be nice to have the fan in front of the cooler to help deflect bugs and whatnot coming in at high speeds

You've got me watching my trans temp while driving around in traffic now and only two or three times has it gotten close to 200.

[chuntag95]

Originally posted by DalDMax:
Is the thermostat built into the fan unit?
The thermostat should definitely be behind the cooler. Of course it would be nice to have the fan in front of the cooler to help deflect bugs and whatnot coming in at high speeds
The probe is in-between the end and the fins about 2 rows up. It is too long to put in from the back, but I might be able to take the cooler off so I can get it in from the back. The thermostat is in the fan controller and has a pot to determine the temp it turns on at. The probe has about 18" of wire going to the relay thermostat "unit" for lack of a better term. Here is the site for Summit Racing (http://store.summitracing.com/) and the part number is DER-16759. You can enlarge the picture to see the probe.

As far as the bug protections, most of the cooler is blocked by the bar across the grill anyway. :rolleyes: I have the Fred scoop still on there to help get the air down there.

[a64pilot]

Chris,
I would put the fan so it blows through the cooler. I think it may last longer if it dosen't get heated by the cooler.

[chuntag95]

A64,
That's my plan and how I had it on the first time. Hope to get it on tonight and have pictures posted before I leave. Don't get mad if I don't make it.

Chris

[a bear]

Chris,
You tryin to get me in trouble. Now you know if this works I'm gonna have to have one. Maybe I can use my Houston, Tx. driving to justify it. Nah! I think I'll just add it to the list of other sneak on mods. She'll never know. :D :D

[chuntag95]

Okay, I got it done. I have a single poll double throw switch with one side going to the ignition on line on the thermostat (temp controlled auto on) and the other going to a relay that applies power directly to the fan for a manual on. I'll let you know how it works out Friday after our trip. I also wired the diode side of a switch to see when the fan turns on with the termostat and put it on top of the column. I'll take that off when I get it set up to turn on when the temp is 150 to 160 on the gauge. I'm in trouble for completing it and better not take time to post pics or I'll be in divorce court. :eek:

[bhinrichs]

I have a 2002. Driving up and down I-76 in north-eastern Colorado, I just ran about 3 hours with the tranny sitting at just a shade over 200. The temp display in the mirror registered between 101 and 107 the whole way.

On my truck, the tranny temp seems to be directly related to the outside air temp. Below 80 and the tranny temp stays below 180. Between 80 and 100, I seem to get temps between 180 and 200, 100 and over 100 it seems to stick to 200 until I stop then it will climb to about 210. When I get going again it seems to go down to 200 again, but, it takes a while. I don't generally tow and I generally run a little over posted speeds.

The coolant temp nevers seems to move once it gets to 200.

I'm hoping that this added fan works out. I've switched to synthetic, been considering the deep sump, though I don't see how that would really help much.

I really appreciate you guys that try these things and let us know.

Thanks,

Bert

[sdaver]

Chris I found the amsoil synthetic tranny fluid to be too slick for my allison......caused much easier limp in 125 hot juice and an occasional limp in the 90 hp mode changed to transynd and the limp problems got much better.....the problems left for good with my trip to Ft Walton. Currently running dex 3 per joe at Suncoast....no limp.......my temps stay less than 200....I have seen more than 200 with heavy towing and consecutive 1/8 mile blasts.......but not in traffic (that I ever noticed)unloaded......good luck and have a safe trip :D dave

[mackin]

Hey Mr Direct Drive .....

Don't look away ,that's right I'm talking to you .... tongue.gif

That's some interesting info you threw out there ... Suncoast recommends Dex III ..... Wonder why ..... Did they give ya a reason ?? I personally would think Transynd would be best....
I do (it's not in my head) feel a bit of a difference that I've switched back, or it could just be I'm saving some grippage for the 26th Dyno Day in CT once again .... ;)

Nah member I dusted that 6'er Saturday night RIGHT AFTER THE FLUSH MIND YOU,I'm no girl .....If your scared stay home,brush your hair ...

Mac :D :D :D


Mac

[jjackson]

sdaver: I am running my '03 stock, and was planning to change to Amsoil syn tranny fluid, have you heard any negative reports from others who use Amsoil trans fluid..? I tow a 5'r @ about 13K pounds. Just got back from 4K trip and w/Dex III highest trans temp was 200, but would like to see it in the 180 range.

John

[pinehill]

Changing from dino to a synthetic tranny fluid is unlikely to provide any measureable reduction in temperatures. The benefit of the synthetic is that it is more resistant to thermal breakdown.

[chuntag95]

Well, I'm waiting on my second fan to come in. I kind of toasted the first one. I couldn't get the blade off to reverse it (missed that in the destructions the first time) and hurt the motor. It made it to KC and back, but died Sunday. I think is was a 100% user related failure, but bought a different brand that I can buy replacement parts for instead of an entire unit. :rolleyes: I am having a bit of trouble finding the perfect spot where the fan will cycle. It seems like it never comes on or it never goes off. I have a switch to manually turn it on if it doesn't come on when I want it to. I also have an LED switch wired up so the LED lights when the fan is on. I plan on taking that off when the setup is dialed in. Unless that doesn't happen, it's temp, but I have consided puting in an LED or light to just let me know it's on as I like the feature. :D

I have done some looking at the extra coolers and there are some out there that have fans on them already. You can get a stacked plate cooler for a little over a C note and the fan for an extra quarter up to a half depending on the number of passes and stacked plate vs. tube. You can get a switch to turn the fan on at 180 and a bypass that allows 10% flow till 180 and then opens to 90-95%. That would be another couple of Cs for that set up. Should have just started there considering the second fan :mad: . All in the name of continuous improvement, huh? tongue.gif

[DalDMax]

Chris,
I've been waiting for anyone else to jump in and say that they are having high trans temps as well.......
Have you had the dealer check to make sure the fluid is flowing as it should? Not sure if there is a way to check for that but...
Question, how long (minutes / miles) does it take for the temps to get up to 200 after the truck is cool like on the way home from work?

[chuntag95]

DalDmax,

I have had the truck in twice for running hot. Also, I had some slipping a couple of times. Both times the dealer said everything is fine and they could not duplicate any problems. I at least have it on record.

My temps don't shoot up fast. I can go for 15-20 minutes or ~10 miles of stop n go before hitting 200 most of the time. I can extend that time by turning on my fan before it gets to 160*. I also have the scoop, so that helps when the fan is not on as well.

From what I have gathered, Allison says we are fine up to 225* as long as it doesn't get there in 5 minutes or something which would indicate a problem. The deep pan and Transynd don't help much. Adding a fan on the stock cooler doesn't help much. Adding a cooler 3 times the size of the OEM does help but more testing is ongoing. Most people are telling me I am overdoing it on this one. I don't want to cough up $3-5K for a new transmission if I can spend $300 and make it bulletproof from a temperature standpoint. Just my 0.0002 (devaluation of the dollar and all). tongue.gif

[ratlover]

Are you some how puting a band aid on things? What did it run totally stock? You were having slipping problems wernt you?

I might be inclined to leave it totaly stock and let the dealer fix it. If they dont know what the problem is then wind her up till it pops. Leave it in regular mode and throw some fire wood in the back and go drag race some civics in traffic till she ****s. Once you get a good one or yours fixed then put the scoop and big pan on and such.

It just sounds like you have an actuall problem, not like you are just trying to improve things......it would suck to improve things to a point so it lives just beyon warranty.

Thats just my .000002(after devaluation and such ;) )

[chuntag95]

Originally posted by ratlover:
Are you some how puting a band aid on things? What did it run totally stock? You were having slipping problems wernt you?

It just sounds like you have an actuall problem, not like you are just trying to improve things......it would suck to improve things to a point so it lives just beyon warranty. I try and stay away from bandaids since they always fall off. tongue.gif I ran 210 totally stock and did have slipping when it was up there totally stock. I can't get the stealer to recreate. It is not consistant. I might try and get it hot and slipping and take it over to them.

I am afraid I do have an actual problem. The question is what is it. Is it a gauge off, an abnormally hot tranny, bad carma, :confused: If I can keep it running cool, then it should go forever. If I cannot, the it will fail (the only question is when). I agree there is a chance that I extend the life till warranty is up. But if I modify early enough, before any damage, it will work out. I need to get a gauge on it and see what it reads like Mac did. I think I am on hold for any other mods till I get the gauge in. If it is close to the factory gauge, then I need to find a different dealer to look at it or add/change the cooler.

[ratlover]

Originally posted by chuntag95:
I try and stay away from bandaids since they always fall off. tongue.gif [/QB]Especially when your not expecting it and at the most inopertune moment, like making soup......and I never seem to relize it till its too late.....

I'd say(and I am about as far from an expert as you can get) that if you had slipping then there is a problem.

[DalDMax]

Chris,
Just pulled this from Allison.com faq page
http://www.allisontransmission.com/service/faq/index***p#121

Note they say high temps shorten the life of the FLUID.


Q. ATF Temperature - What is a "normal" transmission sump temperature?
A. In normal duty, transmission sump temp runs in the 175-220 deg F range (79-104 deg C). Continuous operation above 220 deg F can shorten the life of the transmission fluid. TranSynd is recommended for continuous operations at elevated temperatures.
Back To Top

Q. ATF Temperature - What is the maximum acceptable sump temperature?
A. The TCM will set a sump overtemp diagnostic code at 251 deg F (122 Deg C). At that point, an alternate shift schedule will be invoked that is designed to reduce sump temperature. Additionally, a dash information light will illuminate to inform the driver that the transmission sump temperature is exceeding normal levels.

[chuntag95]

DalDMax,
You made my day. I have Transynd in already. If I don't need to worry till 220, I'm good. Thanks for clearing up the transmission vs. fluid question. Also, I think that if I see the transmission headed over 220, then I will shut down to avoid hurting it or turn on tow/haul. I have not seen that high yet.

[DalDMax]

It sounds like the Allison will protect itself from damage due to high temps by going into a limp mode.

Now that you are feeling better about the trans temp.....How hot is your differential getting? :D

[chuntag95]

You had to ask didn't you? :( I have switches on order and will probably order the connectors, sensors and gauge soon so I can answer that question. Oil Pressure, Oil Temp, Transmission Temp and Differential Temp plus fuel system pressure all available by turning a knob. :cool: I am waiting on the quote for the connectors. The switches and knobs were 10.81 including shipping. :D I just want to build a couple of switch boxes with factory connectors. I think that will make it easier in the long run. I don't trust the oil pressure and transmission temp gauges on the dash, so I will double up those and I want info on the other three. I can never leave well enough alone. :rolleyes:

[BigLakeDMAX]

Chris,

Your temps sound alot like mine runs - I'm stock at this point. When temps are in the 90's, I can hit 200 or slightly over when in stop and go traffic while empty. We just got back from the Black Hills where temps were over 100 (111 f was the hottest), towing our 10k 5th wheel. Temps while towing were same as running empty - what really made a difference was stop and go traffic. I read something from Allison awhile back that idling in park will also cause fluid temps to rise and I've noticed this as well. The highest I've seen is 210 on my factory guage. I did change to Transynd and a deep pan before the Black Hills trip. This did nothing to lower the max temps I've seen, just takes longer to get up there. I usually run Tow/Haul while towing and have experimented with that empty as well. I still see the same temps with Tow/Haul, it just takes a little longer to get there.

I think we're OK with these temps as long as they're occasional and not constantly experienced. The Transynd should hold up better than dino at these temps, so I'm sticking with it. My Allison is the best operating component on this truck - very tight, no slipping, no problems so far and it still sees temps as high as yours. I am interested in your attempts to cool things off a bit as it just seems a good thing to do. I've looked into adding a second OEM cooler - as it has large tubing - with a fan back by the trans in the return line. If it's not too much, I just might do that.

Good Luck,

Don

[chuntag95]

The fan is no big deal, but it only slows down the temp rise like the big pan. If you want to add a second cooler, don't buy another OEM. You can get a nice stacked plate or 5/8" tube cooler for the same price that is twice the size or more.

Another guy on the page replaced his OEM with a unit 3Xs the size. He is reporting better results. I am thinking about using the same type of cooler myself. That or add a second smaller cooler of the same design with a temp controled fan on it. Would probably need to put a shield over it if you mount it underneath. Hmmmmmmm. You would need some 1/2" NPT by 1/2" or 5/8" barbs and cut into the return line. Should not be that hard. Probably even easier than the lift pump. tongue.gif

[Silver Bullet]

Chris,
You will be happy to know I hit 215-220 today driving home from Stewart and Stevenson with 20 qts of Dex III in the back! :eek: I think you travel on the hot side of town!!! My tranny has never topped 200 driving to and from work...but I was on the back streets driving a route similar to your daily travel route and look what happened!!! You may be gettin' your panties in a wad for no reason! :D

[chuntag95]

Hey now SB, let's leave my panties out of this. :mad: tongue.gif

220 Huh? :eek: Bet you were wishing you had a fan you could turn on.
Na Na Nana Na tongue.gif tongue.gif tongue.gif Glad you are changing that fluid since it's been crispyfied now. Are we going to have to scrape it out of the bottom of the pan? According to Mac's chart you are really due for a change now.