Shuddering at very slow speeds?

[Cliffee]

I recently started experiencing shuddering in the drivetrain when slowing to a stop or just when coasting from a stop without touching the gas. Its definately not fuel related almost like the torque converter is slipping.
Any one ever experience this?

[dmaxalliTech]

Well, lets narrow it down a little.. Does it do it in Nuetral when slowing? Do you notice it on accel at same speeds? hmm, I see you have 03 so you have the one piece shaft already, Unless you have a long box with that CC. You could also try shutting the truck right off and see if its still there.. if it is, its in the driveline.

[Cliffee]

It does it in Drive or revers. Nothing in nuetral. If I sit at a standstill and let off the brake wile in drive it will shutter off the get go than smooth out after I start moving. AS I hit the brake I feel it shudder right as its about to stop. Another test I did was put on the emergency brake while in drive, stopped. When I give a tiny bit of accelerator it will shudder just like the engine is missing but its not. I think its a torque converter issue. Iam also starting to notice late downshifts when slowing down.

[403turbo]

My truck did the same thing. Take a look and see if you have any moisture around the bell housing. I just got off the phone with the shop, my truck is in right now for a serious transmission leak. Time for a new TC. They tell me that a mounting lug has actually cracked the weld where it is attached to the TC housing. :eek: :eek: :eek: :mad:

Don't ask me how this can happen without the whole unit being loose but that is the situation. For a mere $2200 I can be back on the road. :rolleyes:

Dmaxallitech...........that drive to Grand Rapids is looking really good about now.

Does this sound like a legitimate diagnosis or is someone blowing sunshine up my A$$?

The TC goes for $1200 all by itself, I am looking at an ATS or Suncoast replacement, then at least I'll know that it will hold together.


The small shutter at about 3 mph when rolling up to a stop without foot on brake was something that my truck did as well, it does feel like the TC slipping somehow.....probably worth getting it documented by the dealer.

But it may be just an Allison thing.

Truckless in NY

Matt

[403turbo]

My truck did the same thing. Take a look and see if you have any moisture around the bell housing. I just got off the phone with the shop, my truck is in right now for a serious transmission leak. Time for a new TC. They tell me that a mounting lug has actually cracked the weld where it is attached to the TC housing. :eek: :eek: :eek: :mad:

Don't ask me how this can happen without the whole unit being loose but that is the situation. For a mere $2200 I can be back on the road. :rolleyes:

Dmaxallitech...........that drive to Grand Rapids is looking really good about now.

Does this sound like a legitimate diagnosis or is someone blowing sunshine up my A$$?

The TC goes for $1200 all by itself, I am looking at an ATS or Suncoast replacement, then at least I'll know that it will hold together.


The small shutter at about 3 mph when rolling up to a stop without foot on brake was something that my truck did as well, it does feel like the TC slipping somehow.....probably worth getting it documented by the dealer.

But it may be just an Allison thing.

Truckless in NY

Matt

[Cliffee]

Jeeez.
At what milage did the shuddering start?

[403turbo]

I bought the truck used, it had 20K miles when I bought it. It shuttered from day 1 with me. I thought it was brakes at first but noticed it even without brake pressure. Like I said it may be a normal Allison thing, I didn't mean to scare you. It may be totally unrelated to my current woes......or not....dunno.

My second thought after brakes was the TC, and I think you are correct, the TC feels like it is trying to get grip but just not holding on. With RPM's on the motor all shuttering goes away. Its just a real low speed, engine at idle thing.

Might be worth checking out, we have seen a few Torque convertor related issues in the last month or so.

[dmaxalliTech]

403.. stock conv for 1200 and ATS for 1500... no brainer there. go with the stage one kit and get it done since your apart...

[George Gozelski]

I have an 02' cc long bed 3500 and I've been experiencing driveline shudder at take off. Does the general only take care of cab and a half trucks that have the shorter driveline? Seems really odd to me if that's the case! Does anybody out there have any current info on the subject? Do the new 3500 crew cabs have a 1 piece or two piece shafts?