Another Tranny problem!!!

I own a 95 toyota 4Runner Limited V6 4X4 with an automatic tranny,and my tranny wont shift out 3rd gear when i first turn it on. I thought it was because I wouldnt let it warm, so I would let it warm up for about 5mins, but still no difference. Ive had this truck for about 2 years now. when I first got the truck I had no problems with the tranny. I would turn it on, take of, and it would shift fine. But as time went on it started to shift later and later, now I can go for about 10-15 minutes with out the tranny shfiting out of 3rd. but once it shifts, I have no problems for the rest of the day. Can anyone help out because I dont know whats wrong!!!!???

Replace the engine thermostat. The shifts are temperature-dependent.

But wouldnt my engine run hot if it was my thermostat???

If the thermostat is stuck open, your engine will take a long time to warm up, or never really reach operating temp.

Thanks for the advice. I'll change it tommorow, and get back to you on what happens.

I replaced the thermostat, and there was no difference. What else could it be? Maybe I need to change my trannys filter and oil???

It's a cheap potential fix, go for it. Sorry the thermostat thing didn't work. Could also be your engine coolant temperature sensor.