If I drive my truck for longer than about 30min I have all kinds of trans problems. First it'll start kicking in and out of lockup, then it'll hang up in 2nd gear instead of shifting to 3rd, the only way I can get it to shift to 3rd is to let off the throttle, it's also hesitant to go into O/D. Now it doesn't always do this, when I first start out it's fine, if I drive for awhile then it'll start. I replaced trans fluid, filter, and both batteries with no success. Any ideas? The trans fluid temp doesn't seem to have an effect, it'll be around 135* and act fine, 30min later still at 135* but now it's acting up. And I don't think it's electrical, because it'll start out shifting fine with no lockup problems. But after I've been driving awhile it starts acting up. Also if it's colder outside it seems to delay the problems, but the longer I drive it the worse it gets, sometimes it'll go away for like 5 min but it always comes back. What do you guys think?

 

Sounds like a bad TPS. Do a search on "TPS" and get all kinds of info on repair and adjustment.

 

But if it was something electrical wouldn't it be acting up all the time? I can about time it down to 30min before it sets in. That's what makes me think it's something internal wearing out.

 

My Tps would act up once in a blue moon,I would change it out that is more than likly whats hapening.

 

Check your battery connections , I had probelms with a 91, would go into overdrive for about first 20- 30 minutes then kick out . Long story short cleaned terminals and everything returned to normal.

 

Your truck has a hydraulic gov. and the only things controlled electronicly are OD and lock-up. How many miles on your truck? B/C what your describing here you have other things to check out. Check your grounds and tps but the hang-up your getting in second it not electrical but mechanical in the trans as charaterized buy your symptoms getting worse as trans heats up.


Richard

 

There's about 95k on the tranny. If I could just get the TC locking and unlocking problem fixed I'd be happy, because I plan on getting a new trans in Spring if not sooner. I'm gonna try cleaning my tps, but what grounds should I check? I already cleaned the terminals and put in new batteries. Thanks.

 

Check/clean the grounds to the chassis and engine block. Its a pain but well worth it if anything just to rule it out.