OT: GM Truck Tranny ? / Problem
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Has anyone else had this happen?
I have a 2002 2500 Avalanche with the 8.1L and 4L85-E Transmission 4spd Auto. It has the 4.10 rear end.
My driveway has a bit of a dip to it, about 15 feet infront of the garage. It drive the AV up to the garage door, and leave it overnight, so the vehicle is pointed nose up by about 15 degrees. When I come out the next day, fire up, and stick it in Reverse, the truck merely rolls down the incline, into the dip, and does not provide power to back up the rest of the driveway for about 20-30 seconds. This is a very intermittant problem. Also, sometimes, the transmission has more problems for the first 30 minutes of driving, by slamming into each one of the gears as it automatically shifts. This is a horrible problem to be having with a brand new truck, purpose built, and purpose bought to haul my boat. I have not had the boat behind the truck during any of these problems, but that is irrelevant. I believe the harmonic balancer and/or the torque converter are having major issues with draining fluid into the pan overnight, like something may have a crack or a hole in it, and it drains only when that hole ends up on the bottom when I park it for the night. Does this sound feasable? I really need some help here. The Chevy dealer has had the truck twice, both times NTF. The second time, they replaced the Valve Body. It is still having this intermittant problem.
Pleease no Chevy/Ford/Dodge/Avalanche battles back and forth on this thread. I bought the truck. I love the truck. I do not know much about trannys, and I need this fixed before the warranty expires. You know how hard it can sometimes be dealing with warranty crap. The dealer makes no money on this, and they like to replace as little as possible. I am about to demand a new tranny. Please help me understand what could be the problem with this one, so I can speak the terms when I talk to the Service Manage.
I have posted this on www.PickupTruck.com and www.ChevyAvalancheFanClub.com. I am looking for ANY and ALL knowledgeable tranny inputs, and OSO has a wealth of ALL, well rounded information.
Thanks so much, everyone.
I have a 2002 2500 Avalanche with the 8.1L and 4L85-E Transmission 4spd Auto. It has the 4.10 rear end.
My driveway has a bit of a dip to it, about 15 feet infront of the garage. It drive the AV up to the garage door, and leave it overnight, so the vehicle is pointed nose up by about 15 degrees. When I come out the next day, fire up, and stick it in Reverse, the truck merely rolls down the incline, into the dip, and does not provide power to back up the rest of the driveway for about 20-30 seconds. This is a very intermittant problem. Also, sometimes, the transmission has more problems for the first 30 minutes of driving, by slamming into each one of the gears as it automatically shifts. This is a horrible problem to be having with a brand new truck, purpose built, and purpose bought to haul my boat. I have not had the boat behind the truck during any of these problems, but that is irrelevant. I believe the harmonic balancer and/or the torque converter are having major issues with draining fluid into the pan overnight, like something may have a crack or a hole in it, and it drains only when that hole ends up on the bottom when I park it for the night. Does this sound feasable? I really need some help here. The Chevy dealer has had the truck twice, both times NTF. The second time, they replaced the Valve Body. It is still having this intermittant problem.
Pleease no Chevy/Ford/Dodge/Avalanche battles back and forth on this thread. I bought the truck. I love the truck. I do not know much about trannys, and I need this fixed before the warranty expires. You know how hard it can sometimes be dealing with warranty crap. The dealer makes no money on this, and they like to replace as little as possible. I am about to demand a new tranny. Please help me understand what could be the problem with this one, so I can speak the terms when I talk to the Service Manage.
I have posted this on www.PickupTruck.com and www.ChevyAvalancheFanClub.com. I am looking for ANY and ALL knowledgeable tranny inputs, and OSO has a wealth of ALL, well rounded information.
Thanks so much, everyone.
Last edited by Sydwayz; 10-09-2002 at 04:35 PM.
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Well, just document that you reported the problem under a warantee period. Because I could show that I had a warantable repair I was sucessful with having repairs covered outside of the milage/time window.
I'm no trans expert, but the hesitation does sound like a pressure problem. I would agree with your idea of the trans bleeding down.
I'm no trans expert, but the hesitation does sound like a pressure problem. I would agree with your idea of the trans bleeding down.
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How long are you letting the truck warm up ot operating temps??
Under my search for the last 2 months of trucks I have been informed by several owners and a couple dealers that the most common complaint about the allison tranny is the warm up time.
The computer is programmed to obtain operating temp and/or pressure being it will allow it to shift.
Does not matter if is 'warm' outside.
Cold winters it takes longer.
Under my search for the last 2 months of trucks I have been informed by several owners and a couple dealers that the most common complaint about the allison tranny is the warm up time.
The computer is programmed to obtain operating temp and/or pressure being it will allow it to shift.
Does not matter if is 'warm' outside.
Cold winters it takes longer.
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This is not an Allison Tranny. It is an M32 4spd Auto. Bsag, (Brett Dean) who sold me the truck, just called me and explained this is somewhat common. I am still not sure. At least the initial shift/roll problem. The torque converter is draining depending on where the teeth end up each time I park it. Puzzles me though, as my Tahoe did not do this at all. As far as the continuted slamming shift problem for 30 minutes or more after I start to drive it, that could be a bad pressure sensor/sender in the tranny, or a problem with the TPS on the engine, but the TPS would lead me to believe I would have more problems. I am going to watch it for a while; especially as it gets colder; and maybe find a GM dealer with a sharp tranny specialist to have everything looked at. I have over 30K left on the warranty, but I do not want these slamming and shifting problems to wear the transfer case, u-joints, drive shafts, and differentials to a point they are going to blow right after the warranty expires.
Thanks MFB and Cord for your repsonses. Thank you Brett for the call. I have owned a lot of vehicles, and never had something like this. I am going to keep an eye on it. My brother-in-law has the exact same truck, and parks the exact same way I do, tilted nose up. He has had not problems with over 10k on the truck.
More inputs appreciated.
Thanks MFB and Cord for your repsonses. Thank you Brett for the call. I have owned a lot of vehicles, and never had something like this. I am going to keep an eye on it. My brother-in-law has the exact same truck, and parks the exact same way I do, tilted nose up. He has had not problems with over 10k on the truck.
More inputs appreciated.
Last edited by Sydwayz; 10-10-2002 at 11:01 AM.
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Sydwayz, I think I had the same problem as you. Does it shift like it has a shift kit, really bang the gears hard. If so, thats what mine did. The dealer said the solenoid in the trans that makes it shift smooth had a broken wire. They didn't even open the trans to fix. Saw the parts replaced, not a trans man but it has worked perfect since. Just a thought hope this helps.
mike
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I sorta have the same problem on my Jeep Grand Cherokee......granted the truck has 116K miles on it so i'm sure that plays a big factor in this but in the mornings when i start off, the truck wont move right away when shifted into drive or reverse. I start the truck and shift into neutral for like 30seconds. I guess it builds up pressure through the trans and then i shift no problem. This only happens over night when it stands for a good 8hours. I look at it this way...it keeps me from tearing up the engine when its cold! This way atleast the engine has had some time to circulate oil and trans is lubed good too. ![Smilie](/forums/images/smilies/smile.gif)
This is no excuse for a new truck though...
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This is no excuse for a new truck though...
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BE CERTAIN that after each time you brought the vehicle in teh service writer closed out the work order. If not, it will appear that the vehicle was only in once. If you have to lemmon law it this can abe a big stumbling block. Just make certain it is closed out and you get a new workorder for each time you go in. Good luck.
Shane
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Thank you everyone that has responded so far. I think I am going to find another service dealer; one with more experience on HD trucks. Thank you especially, Mr. Goodwrench.
I have gotten a few responses from the other two boards, but nothing like the responses, PMs, and calls from here. OSO truly is a huge help.
I have gotten a few responses from the other two boards, but nothing like the responses, PMs, and calls from here. OSO truly is a huge help.
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Brian, which dealer are you using now??
Wally-you have the infamous Chrysler hard seals, it will get owrse eventually but a change with the new Chrysler spec trans fluid might help(or maybe not) so you could just wait till it pukes all the way.
Wally-you have the infamous Chrysler hard seals, it will get owrse eventually but a change with the new Chrysler spec trans fluid might help(or maybe not) so you could just wait till it pukes all the way.