Torque Lock Fix?

[99gmccrew]

While towing up some very steep hills I noticed my trans temp climbing to dangerously high temps, around 240 F to 250 F. I was telling a friend of mine about the problem and he told me of a way that he fixed the problem on his dodge cummins.
Apparently he found a wire from his trans that he could ground to his dash using a toggle switch that would lock his TCC manually when he needed to. He stated that it was only for locking the TCC and wouldn't shift unless the switch was off. Has anyone done this with a 6.5l or heard of why it would or wouldn't work? I'm thinking it may throw some codes.

Thanks

[LucasEnglish]

I know thay sell something like that for our trucks. I feel the only way to relly fix that problem is to run a external cooler. My truck used to get up around 250deg With the biggest B&M cooler thay make it now never gets over 180deg. I still run the radator cooler also. Helps keep the tranny a constant temp.

[HowieE]

Yes you can lock the convertor, but on the 97s and newer you run the risk of settin an 0742 code. The newer computers compare slip speed between the engine and the output of the trans while the convertor is locked. Under heavy load if you have any real power in your engine you can exceed the slip speed limits when shifting into OD and set this code. Once set the truck goes into Limp Mode and will produce very hard shifts until the truck is shut off for more than 30 sec.

BD sells a Torque Loc for the 4L80 trans but they have not solved the above problem.

If you are interested in using the BD it can be used if you are willing to select setting manually while driving. I have had to use mine manually for 3 years but by doing so can hold my trans temperature at 150 while the convertor is locked and seldom see it above 180 on hills that I have had to run unlocked. Its tricky but worth it if you are towing with a newer 4L80.

With the BD I can run in 3rd at up to 60 mph in areas were I want power but do not expect to go above 60. I can also lock the convertor in 2nd. above 33 mph for the real hills.

[rjwest]

see " cheap way to get tcc to lock in 2nd " post

Works great in 2nd and 3rd.
and will hold 4th untill it downshifts to 3rd