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Murray the Cop
04-25-2005, 11:58
I have been dealing with this problem from when this truck was new in 03. I will sart from the beginning to give you the best overall picture I can. Bought new in 03, first diesel. Ran it for say 10,000 and caught the HP bug. Tried a Quad box( 135 hp) that shifted so hard sent the truck into limp mode a few times. Got rid of it fearing it would hurt the tranny. But shifts were never so crisp as when I had it and never again since. Went with a juice and found the shifts very mushy and delayed. I thought it was the defuel option, which in part I'm sure it was or is. I now have 50,000 on the truck and have been trying everything to get rid of the delayed shifts I am getting from 2 to 3 mostly and sometimes between other gears. I have been to Michigan twice. Once to have Eric put in a stage three, that didn't help and completely screwed up the first tranny. Fluid pouring out of the breather every time you got on it. Then decided that a new tranny would fix it so again headed to Michigan so Eric could install a stage 5 from suncoast.( From LI New York, Mind you) All seemed fine untill after the learning period and the truck was right back to shifting like ****. Delayed shifts that seem to be dalayed longer the more HP I put through the engine. Meaning that in stock form now you can hardly feel the delay and as I increase the HP it gets worse and worse. Which has been the problem from the beginning. Tried to have an ECM nad TCM programmed by Eric but it didn't work out. For some reason niether one came back from him with my vin in them. I have since purchased a TECH 2 to see if I could figure something out but really have no idea what I am doing with it. The shift feels almost like driving a standard and just pessing the clutch in the middle of driving. Not sure if you get the picture but the most predomonant is the 2 to 3 when it happens and it feels like a slip for say 2 seconds then it shifts. I am about to give up on this truck and trade it in or just sell it and go with something else. I could relly use a little help to get this figured out. Even a recomendation as to someone reliable in the area would be much appreciated. The drive to Michigan is ridiculous from here and it doesn't seem to help anyway. Thanks.

More Power
04-25-2005, 20:03
This has been a puzzle I've considered for quite some time. Add more power, and the slow/lazy shifting gets more pronounced. I took a couple of BD's Allison techs for a ride in Lil Red this past Saturday to demonstrate this very issue. What I'd like is for the Allison to upshift like a performance TH400....

The top performers in the quarter mile are using a combination (programming, power products, Allison build) that produces faster/firmer shifts. Part of the answer is understanding the "adaptive learn" the Allisons use. Drive it easy, and it'll shift easy. Drive it hard for a long enough time for the Allison to learn the drill, and it'll firm the shifts. Unfortunately, a typical driver can't hot-rod to the track. I'm told some guys are using two TCM's - one for the track and one for street use. Swapping in a firm shifting adaptive learn TCM at the track is supposed to help with performance.

MP

Murray the Cop
04-26-2005, 04:58
Driving it stock except for an exaust has been a pleasure as far as the shifts go. I can still feel the slip but not nearly as bad. Can't wait to tow the 5th wheel with the truck stock. I guess I'll have to figure in a little more time traveling. I have an ECM and TCM waiting to be programmed. I think my problems might have something to do with the effect of the first quad tunner on the ECM. I do remember having to bring the truck back when I first got it for a tranny reprogram because of some weird shifts ( no reverse or something, can't remember exactly). I have tried differnt combinations of programming etc. to get better shifts to no avail. I'm not sure the shift I have is the same thing you are talking about. This slip shift happens anytime in any gear and is really pronounced. If you were standing out of the truck you would say to yourself, that guy needs a new tranny. I appreciate the reply but am not really sure where it leaves me. Are you saying that this is what I got and there is no fix? Is the TSS, or whatever its called, a full reprogram of the ECM? Might be worth trying.

More Power
04-26-2005, 07:34
It's hard to know whether what you're describing is within the "normal" range of transmission operation, or not. I suspect that if your trans was slipping more than it should it'll build heat quickly while towing.

After just completing a 1200-mile towing excursion with a 7500-lb trailer, I never saw trans temps above about 190, even in stop-n-go freeway traffic on 405 near Seattle. This was with Tow/Haul engaged. T/H firms shifts and locks the torque converter in gears 2-5.

Check your transmission ATF for fluid quality. A slipping Allison will darken the ATF.

MP

Jim Brzozowski
04-26-2005, 08:41
Think you hot rodders should find some computing guru to make something to diable the adaptive learning part of the computer and put in its place a selectible switchable shift shift firmness so you could run soft on the street and burn the tires on the strip. Surely there is someone out there that can do that. I know it would get really uncomfortable to have one that chirps the tires at every shift on the street, but for the best times you need quick solid lock up on the strip without any defuel.

Inspector
04-26-2005, 19:52
Since I tow heavy I have noticed and can see on the Attitude showing what gear I am in that when the trans downshifts it will sound and seem like a slip until it locks. It will stay locked when it then upshifts. I for some time thought that it was slipping but being able to see what was going on has eased my mind. I tow in level 2 only and tow/haul and I don't rush into anything while towing. I just let the trans do the thinking. I love this truck. By the way I have had great service from the Edge box.. Great for towing.
Denny

Murray the Cop
04-28-2005, 04:13
The slip shift is from 2 to 3 on medium to hard accelleration after the truck is warm. It will happen under the same conditions each time but not every 2 to 3 shift. I find it hard to believe it is in the tranny being a complete replacement and having the same problem before and after it was done. I appreciate the attempts to help but I'm still where I started. I don't run on a drag strip, the truck is an everyday driver and used to tow my camper for family vacations. The added hp is for ease of towing and a little fun the rest of the time. It is not a question of the problem I'm feeling being normal. The dmaxallitech is the one who did all the installs and felt the shift. If it was normal I'm sure he would have said so. Just wish he would have felt it before the work instead of going on my description. If he would have had any feeling at all that the shift wasn't caused by bad clutches in the tranny, I would have saved my time and money and dumped the piece of **** then. I think there is some sort of electrical problem, and now that the warranty is up, no one is willing to chase it. To add insult to injury I was offered 19000 on a trade at a dealership. Enough complaining. If anybody has an idea of where to look for the problem please post. With all do respesct, I do not need driving lessons or ideas about how it might be normal. Thank you

Sincerely, Super Frustrated

madmatt
04-29-2005, 19:45
see my post under your previous posting about your tranny problems. a lot of shifting complaints come back to fuel system problems.