I read through the transmission posts but I didn't really see the same problem that I am having. I have a 2000 Tahoe, 5.3L, 4wd with approx. 145K miles. For the past 6 months toa year I have noticed that when I try to speed up to either pass or go up a hill the truck will shake instead of downshifting when I press the accelerator. This doesn't happen everytime but it seems to have gotten more frequent lately. This seems to happen no matter what speed I am traveling. When the problem first started I don't recall it occurring as frequently as it seems to now. When the truck begins to shake I can press the tow/haul button and usuallythe transmission will immediately downshift as it should and the shaking will go away. Since it happens when the tranny should downshift I was wondering if there could be something wrong with the torque converter.

I had the transmission fluid flushed around 75K miles and the filter replaced about 15K miles ago. I believe the solenoids were also replaced when they replaced the filter.I rarely haul anything and the truck has only been off road a few times. When the problem first began to occur I took the truck in to my mechanicwho also rebuilds transmissions. He drove it but he said he wasn't sure what was causing the the problem but he suggested that it may be the torque converter.

I'm sure someone else has seen this problem andI am looking forward to hearing what the solution is. Thanks in advance!

 

I'd check the motor and transmission mounts, make sure there not torn.

 

I hadn't thoght of that, I'll check the mounts. I don't notice the problem when starting from a standstill, only when trying to pass or increase speed.

 

i have a 2000 tahoe 5.3 v8 4x4 the transmission stopped working in all gears. had it towed home.the next day i started it and put it in gear and it's been working good iv'e drove it around the yard but not on the road. can anybody tell me what might be wrong with it thanks tim