Has anyone ever had the shift solenoids in their auto trans start to go bad? My trans is shifting very hard when the fluid is cold, but when it's up to temp it's normal and smooth. i did some googling that seems to be pointing towards bad "shift solenoids"? My starter went out last week, so i'm familiar with the concept of solenoids slowly going bad until they fail. Would it be logical to assume that when the fluid is cold and thick, the weak solenoids are having a hard time doing their thing?

 

Try a stronger battery. The solenoids are electric so when the truck starts up on a weak battery the transmission cant shift as well until the alternator can supply a strong current and boost the battery. I went to an Optima Red Top that has higher CCAs than the stock battery did and the transmission's moring sickness went away.

It had the same effect on my Lexus IS300.

 

Anyone?

 

That's interesting, I would have thought the voltage with the engine (alt running) would over come a low battery but it is worth checking. Especially if both the battery and alternator are marginal.

 

The Alternator on these trucks is very weak at idle, so all of the accessories are reliant on the battery right after startup. I've considered the 140amp upgrade using a GM alt.

http://www.ultimateyota.com/index.ph...6&topic=9965.0

 

Does it sound to you guys like this could even be a shift solenoid thing? or does it sound like more of a valve body thing? or Insert other option here???