[v8s10]

i've got a 92 yukon 4x4. Having issues with the lock up torque converter. what is happening is. It locks up as normal when truck is cold, but after about 5 minutes, it unlocks. while cruising on the highway it stays unlocked, but when i get to a hill and give it more gas, it will lock, then when i ease off the gas, it unlocks again. I would like to fix the problem properly instead of installing a switch to lock it manually. what actually tells it when to lock and unlock? thanks for any help.

 

[Hogg]

Installing a TCC lockup switch doesnt necessarilymean the TCC will lock.

Does your cruise control work?

Maybe the brake switch is going out? Whenever the brakes are applied the TCC unlocks.

peace
Hog

 

[brian0605]

It sounds like a vacuum switch problem. I am not 100% sure how they set up the O/D on that. But I know they used vacuum switches to activate lock up on some set ups, so that when vacuum increased and stabilized at cruise it would close and engage the torque converter. When you give it gas it would cause the vacuum to drop and open the switch and unlock the converter. Take a look at the vacuum switches and wiring to them. Just a suggestion!!!!!!!! Brian

 

[v8s10]

i have replaced the brake light switch and yes the cruise control works great. the torque converter is locking up...just seems like not at the proper time. and it could be a vacuum problem. It is a 300 hp crate engine with edelbrock intake and throttle body adapter, mild rv cam. wondering where does it get the vacuum signal?

 

[brian0605]

I don't know on the stock set up? But you should be able to take it to a reputable local transmission shop and they should be able to clue you in on how to get it to work with the edelbrock. Good luck.Brian :thumbup: