4l60e Super Harsh 1-2 Shift
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 878
Likes: 2
From: BC
4l60e Super Harsh 1-2 Shift
I'm trying to diagnose a really harsh 1-2 shift with a 4l60e. Its not actually in a Vette but a Suburban.
The transmission seems to shift fine, not slip and lockup works etc. But the 1-2 shift is like having a truck driving in the back of you when it changes.
So the problem is:
The 1-2 shift seems late
The 1-2 shift is very servere
I can ease the trans through the 1-2 shift by closing the throttle when I think its ready to change. It still produces a firm shift but at least you don't suffer whiplash.
I have access to ALDL and its using the E6 (not to be confused with the more common 6E) deffinition. No engine or transmission error's are currently stored.
I've found several possible answers online but neither indicate a way to diagnose them.
Any help greatly appreciated
The transmission seems to shift fine, not slip and lockup works etc. But the 1-2 shift is like having a truck driving in the back of you when it changes.
So the problem is:
The 1-2 shift seems late
The 1-2 shift is very servere
I can ease the trans through the 1-2 shift by closing the throttle when I think its ready to change. It still produces a firm shift but at least you don't suffer whiplash.
I have access to ALDL and its using the E6 (not to be confused with the more common 6E) deffinition. No engine or transmission error's are currently stored.
I've found several possible answers online but neither indicate a way to diagnose them.
Any help greatly appreciated
Drifting
Joined: Aug 2006
Posts: 1,624
Likes: 2
From: Canandaigua New York
Had the same problem with my 98 Silverado.
We thought the TCC was stuck and it turned out it wasn't.
The dealer put in another trans (under warranty luckily) and while doing it discovered
the wiring, going to the trans, was pinched between the tranny and body, which frayed the wires and shorted them out.
I would start with checking the harness.
We thought the TCC was stuck and it turned out it wasn't.
The dealer put in another trans (under warranty luckily) and while doing it discovered
the wiring, going to the trans, was pinched between the tranny and body, which frayed the wires and shorted them out.
I would start with checking the harness.
Le Mans Master
Joined: Feb 2005
Posts: 6,479
Likes: 565
From: Clearwater Florida
..... My '93 Suburban shifted hard 1-2 but it wasn't late ... kinda like it had a shift kit in it for 1-2 only ... Thursday before the 4th it broke after only 304,000 miles ... I spent the 4th weekend replacing the trans but haven't opened the old one yet ... my guess is the reaction planetary disintegrated by the junk in the pan ..................
