Cruise Control

[Onebigcanuck]

2001/2500HD/SB/4x4/Dm/Al

I just took my first trip this year and I've had all the recent updates to the computer.

You can take it to the "BANK" with a new even heavier 5th (CGVW 18,650) it pulls no problem in overdrive and lugs great at 1800 R.P.M, even when climbing mountain passes.

What a diffence from last year

[AB_DURAMAX]

That's great news.....it was a bit frustrating in the mountains last year!!

[ram/tx]

Onebigcanuck...What updateds did you have done? I just bought a 2001 with the Allison and all I pull is a 3000 lb Bass Boat and my tranny shifts out of overdrive on the little hills we do have here in Texas. Does the dealer know about these updates or is there a place I can go to read about them and take to the dealer to make him do them? :rolleyes: :confused: Thanks for any help. This is my first Diesel and I am pretty well lost. Did yours have a hard shift from 2nd to 1th when you come to a rolling stop and then try to take off? Sorry for the long post.

[DmaxMaverick]

ram/tx

With most dealers, you have to play the game by their rules. Go to your dealer with the truck and complain that the tranny shifts too often on small hills, and it has the idle flare (lopey idle). Also add that the filterminder is always sucking down. This will create common complaints with common remedies. You will get the PCM/TCM updates and an updated air box (and a new filter element as well), if it doesn't already have one. You can tell if you have a new box if it has no snorkel, and is open on one side into the engine compartment.

If you go to the dealer and ask for all the new updates, they will tell you that GM requires a complaint that addresses the issues before they can get them. When you come back with complaints, they will likely spend a bunch of time trying to duplicate the complaints (you gave up your hand the first visit). Some dealers will just do it and fill in the blanks, but they are rare.

Definitely get the updates. They really make a difference.

[Vette Racer]

Hey, I have a 2002 cc dually and it downshifts every little hill with 6k on it. Do you think it would help if I took it back to the dealer and claimed the above problems.

[DmaxMaverick]

Vette Racer

If you think that it shifts too often, then by all means complain to the dealer. There is recently a newer update that addressed a few things. At the very least, GM will be getting the complaints and eventually (hopefully) eliminate the issue all together. Problem is, some are actually complaining that the engine lugs too much and doesn't downshift soon enough, not allowing it to use the full rpm range. Guess they will never please everyone, nor will they try. I would like to see them adopt multiple shift paterns, tuned to the owners needs/requests. It wouldn't be that difficult.

[Redhawk]

Would it help if you complained to the dealer that the problem happened mostly when towing? I doubt they could expect you to bring the truck and trailer down to the dealership to try and duplicate the problem. I think they wuld just go ahead and make the updates.

[Onebigcanuck]

For Ram Tex,

The update I got was Part number 15097103 CVN#0000812F.

Hope this helps

[ram/tx]

Thanks DmaxMavrick and Onebigcanuck for the information. I will get my truck down to the dealer this week and complain about the towing in cruise and lopey idle. DmaxMavrick, the air box in my truck has the flat top on it and I can see the bottom of the filter between the finder and the hole in the box. I suppose that I have the updated box in it. Don't see no snorkel. The truck does surge if you try to idle at about 2 to 3 mph. The wife almost runs over me everytime we hook up the boat. I had to sell my first born just to buy this truck and I will have to keep it for a very long time. I really like this site, seem like some good people and a wealth of information for us first time diesel owners. smile.gif

[HD Hauling]

The only reason that people think that this engine is lugging to much is because they don't know anything about diesel engines in how they have their power at low RPM's not the high RPM's like the gas engines.
The people should have been showed a tape showing what to expect from diesels.
This tape should be made from a company that knows how diesels are to perform because the GM Engineers only know one thing and that is keep the RPM's high when pulling.
That way you will not lug the engine to much but shorten it's life by the high RPM's!!
Besides all the GM trucks are good for is playing in the mud or pulling a boat like the commercials show on TV.
That's what you need a HD for?
Have a good day

[ram/tx]

I reckon all sites have the know it all's and the guy's post above mine proves this point. It was my money and if I want to pull a boat with my HD that is my business and you can go pull the world with yours if you want to, that is what makes the world go around, different strokes for different folks. HAVE A SAFE AND HAPPY DAY HD Hauling!!!!! smile.gif smile.gif smile.gif

[kerry witherspoon]

Hi one big, i am also calgary what dealer do you use, Ialso tow a fith wheel and a boat .
Love the Duramax

[Onebigcanuck]

Kerry,

I use Keith in Okotoks, Dennis is the Service Mng. and is a great guy

[HD Hauling]

Sorry fellows if I stepped on any feet.
I don't care what you guys pull with your HD.
I pull a 33' 5th wheel and every time I hook up to it I have to listen to this so called Built Like A Rock of a truck, scream every time it hit's a little bump in the road and then if your hitting a head wind it just stays in 4th unless you let off the peddle.
The point is if they got such a good product of Horse Power which they do, why treat it like it might break if they work it to hard.
Put the truck out their and let it prove itself by working it the way a diesel should be used.
And if they have a problem fix!!
Don't sit their behind their big degree's and hope nothing goes wrong so they don't have to face the consumers and say we have a problem.
They got big shoulders at least they should!
Again I apologize but I get carried away I guess because I've delt with diesels for years and when the GM Engineers said they "Don't What to Lug the Engine to Much" they stirred up a Bee's Nest!!
Have a Good Day
HD

[randym]

Is anyone aware of any upgrades for the 4L80E which I have in my 8.1 Suburban. When towing our 8500 lb TT I find it very difficult to tow in 4th gear and totally impossible to tow in 4th gear with the cruise control engaged. Seems to be the same inept programming that GM selected for the Allison which is unavailable for my application. Any insight would be greatly appreciated.

[hardwood]

HD Hauling,
I couldn't agree with you more about GM's fear of lugging the engine. Diesels produce the most significant proportion of their torque at low RPMs, like at starting from a dead stop. However, with the new calibration for the allison concerning 2-1 downshift and cruise business, your towing/hauling experiences will be much improved.

I, as well as you, apparently purchased our trucks for heavy loads, and we have high expectations, as I think we should. Before the allison update, I was disgusted with the performance of the hauling of my truck with trailers and different loads. Now, though, it is much improved. The update applies to 2001 and 2002 models.

Now if I could just find a pickup bed that is "really" heavy duty.

[ram/tx]

HD HAULING...I'M sorry if I jumped to soon. I thought you were making fun of me for buying a HD and all I pull for now is a boat. Well I only pull a 3000 lb boat and the Allison downshifts on these little hills in Texas with this light load and I can see why people like you who really do pull a heavy load with it, up big hills, would get flustrated with this downshifting. I traded in a 99 Chevy Z71 because of this same problem and now I have a Diesel that does the same thing, and this is why I am pi$$ed about this HD, and am just trying to find someone who had a fix for it. I didn't want to buy a 6 speed, because I'm to old to act like I'm driving a big rig, I just wanted to sit back an let the truck do the work, but as you said this Allison will drive you crazy downshifting and upshifting on every little hill you go up. I hope the new Calibration update everyone is talking about will fix this problem. Have a safe day and God Bless America.

[HD Hauling]

Hi fellows,now that we got that out of the way I keep hearing about a new calibration for the shifting.
I had one done last fall about the shifting,is there another one that is newer?
That one just left the mph drop to 4 mph and then shifted instead of the 1 mph drop.
Again there they should forget the mph drop and instead let the RPM's drop 200-300 and let it shift.If they did that you wouldn't hear so many complaints because it wouldn't shift so often unless your in the mountains.
I'm not home alot so I don't get on here that much.
Thanks
HD

[hardwood]

HD Hauling,
Check out the thread:

http://forum.62-65-dieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=7&t=003061&p=

It covers the allison update and 2-1 downshift phenomenon some of us experience. Mark5678 had his TCM and PCM calibrations checked at the dealer, but they said he didn't qualify for the new TCM calibration. You may want to have your truck checked at the dealer to see if you qualify for the latest and greatest updates.

I will note that the new calibration affects the fast learn, so when one's truck experiences a new driving condition, i.e. towing up hills, it seems to learn the shift patterns quicker than before.

I would suggest checking the thread I linked to provide more information about the new calibration.

[jallen]

Had the tech @ my Dealer update my TCM & now He will drop to 1800 rpm b-4 shifting down, & when driving in "normal" trafic conditions the trans shifts @ about 2000 - 2200 rpms where it used to shift arround 2500 or so.

I'm really happy with this modification. I did have to COMPLAIN harshly & explain that a few years ago I would simply adjust the detent cable by a notch & back off on the cruise servo a notch as well.... BUT now it is all COMPUTERIZED to keep me coming back to the dealer for work.

Thanks all this a GREAT FORUM, I have recieved lots of answers & explainations from the WEALTH of KNOWLEDGE we Share here.

Thanks

2002 K2500 D/A, 4X4
Crew Cab, Long Bed
Jordan Ultima 2020
DTA Ultra Boards With 4 inch drop
R D S Mfg. 60 gallon tool-tank
2002 Wilderness 32 foot 5 er
mine came with MPG smile.gif tongue.gif :D

[jallen]

Had the tech @ my Dealer update my TCM & now He will drop to 1800 rpm b-4 shifting down, & when driving in "normal" trafic conditions the trans shifts @ about 2000 - 2200 rpms where it used to shift arround 2500 or so.

I'm really happy with this modification. I did have to COMPLAIN harshly & explain that a few years ago I would simply adjust the detent cable by a notch & back off on the cruise servo a notch as well.... BUT now it is all COMPUTERIZED to keep me coming back to the dealer for work.

Thanks all this a GREAT FORUM, I have recieved lots of answers & explainations from the WEALTH of KNOWLEDGE we Share here.

Thanks

2002 K2500 D/A, 4X4
Crew Cab, Long Bed
Jordan Ultima 2020
DTA Ultra Boards With 4 inch drop
R D S Mfg. 60 gallon tool-tank
2002 Wilderness 32 foot 5 er
mine came with MPG smile.gif tongue.gif :D

[HD Hauling]

Hi fellows,thanks for the come back.I'm going to check out what you have given me.
Will take along a copy to show the GM tech at the dealer.Will let you know what happens.
HD smile.gif

[TBC]

Had the updates done on mine last Monday and it makes a big difference in the way it shifts and pulls. It doesn't drop out of OD on overpasses and slight grades any more. I have seen other comments on this forum that they too are able to tow in overdrive and cruise in the mountains. My dealer did it while I waited and it only took about 30-45 minutes and I was gone. The service bulletin number is 010730034 for excessive shifting (busy shifting).