4l60 torque converter won't stay locked

A local automatic shop said I can tap a certain wire in the plug on the side of the transmission, then run it to a toggle on the dash, ground the switch and done. $5 lockup switch should work.

lt1tyrell wrote:
It's a 92 k1500, Trans temps in the pan are hitting 205-210 when trying to maintain 55-60mph.

I wouldn't be worried about 210*F. Engine oil will be that hot.
Just change your tranny fluid more often if it worries you.
Go to DEXRON-VI. It's the best.

Does your cruise control work? If it doesn't, check your brake switch. My torque converter would lock and unlock right away and I noticed the cruise control wasn't working either. A bad brake switch makes both not work correctly.

if you unplug the throttle position sensor it will lock the torque converter

Ok thanks guys

ECM still controls converter lockup going back into the 1980's.

I would not override the ECM's decision on when to command TCC engagement, the ECM will engage at any speed the conditions are met. To do otherwise may damage the converter, the computer know how much torque the TCC can withstand.

You basically have 2 options here, deeper reduction in the final drive or smaller load on the hitch.

lt1tyrell wrote:
Yup I know it is a 4l60 with a tv cable. Already has a big cooler installed and a gauge with the sender in the pan. It works great other than the fact that I can't keep it locked.

Ok that changes things, lol.
Check into the throttle valve cable adjustment procedure for that truck and see if that helps.
Other than that or TCC solenoid flaking out, you are only making about 190 hp at the crank with that TBI motor.....I had a 93, it was weak.....had to mod it and eventually get a bigger TV.

Yup I know it is a 4l60 with a tv cable. Already has a big cooler installed and a gauge with the sender in the pan. It works great other than the fact that I can't keep it locked.

lt1tyrell wrote:
It's a 92 k1500, 6,000lb high side trailer. Won't stay locked up over about 45-50mph. Trans is in good shape, is there a way to wire the torque converter lockup solenoid to a toggle switch so that when towing I can hit the switch? Trans temps in the pan are hitting 205-210 when trying to maintain 55-60mph.

Ok, 4L60E came out in 1993. I think the 700R4 was renamed 4L60.... No E in 91 or 92.

Look at the throttle linkage for a throttle VALVE cable and or lockdown cable. If you have these it is not computer controlled.

It's a 92 k1500, 6,000lb high side trailer. Won't stay locked up over about 45-50mph. Trans is in good shape, is there a way to wire the torque converter lockup solenoid to a toggle switch so that when towing I can hit the switch? Trans temps in the pan are hitting 205-210 when trying to maintain 55-60mph.