1994 Sierra transmission problems

I have a 1994 Gmc Sierra, extended cab, stepside, 4x4, 350 with 39,000 original miles. The truck is all original except a 3" body lift I installed and upsized tires from 245's to 31-10.50's about one year ago. I've had no problems until last saturday. The transmission(4L60) seems to disengage or something after an extended period of sticking in 1'st gear. It will do this for about a minute or less, and shifting through the gears seems to help the transmission begin working properly quicker. After this first episode, it won't do it anymore until parked for several hours and allowed to cool again. I have checked the fluid level since this began, and flushed and filled the transmission and replaced filter several months ago. I adjusted the linkage and the shift switch on the steering column per repair manual. The problem still exists. I would appreciate any help or advice. Is this a fluid heating problem? torque converter?

My vss was bad. $100 later,everything is great.

4l60e Trans Is Know For Problems Its Sounds Like Your Shift Servos Or Force Motor In Trans Wanting Io Go Out My Did Same Thing Is About A 500$ Job Good Like

[QUOTE=blackhawk5177]4l60e Trans Is Know For Problems Its Sounds Like Your Shift Servos Or Force Motor In Trans Wanting TO Go Out My Did Same Thing Is About A 500$ CHECK OR THERMOSTAT TRY 195
GOOD LUCK

I have a 95 Sierra that had the same problem: it stuck in 1st often. After much money spent on the tranny I found the problem was not the tranny but the ignition switch on the steering column. A new one was installed and I have had no problems with the tranny sticking in 1st anymore.

i have a 1994 gmc sierra truck and the transmission wont change gears after going past 28 MPH. it goes into first gear but after that it acts like its in nuetral. its an automatic

anyone? how about does anyone know where i can get an online guide for installing/troubleshooting my trans? if you do please email me at youkai_dog_demon@yahoo.com

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