Engine/Transmission (1994 - 1998) '98 12v auto transmission

Seeking some advice. This truck has a switch installed that locks the TC. Just put a 75hp fuel plate in; woke it right up. Then a cab over camper gets thrown in the back that weighs about 2K. With the TC locked, the trans slips, no surprise considering the trans has over 200k on it. The advice I'm seeking is this: can I get away with just replacing the TC with a more robust one or should the trans be completely rebuilt? If just the TC is replaced what is the next weak link? Prior to the new plate and install of the camper The trans fluid was changed. It is now burnt. This truck has an easy life as it belongs to a 78 year old man and he takes it pretty easy. ( I have no doubt he had to "try it out") The truck has gauges, 4" exhaust, kdp, good air filtration, etc. I warned him, more power is a slippery slope my friend....

Thanks.
Jon

 

A lock up switch has to be used wisely.My guess it was not.Throwing added power at an old trans has never been a good idea.Pull the trans and have it built for the added power and do some research before using a t/c lock up switch

 

I installed 215 injectors around 2001 in my '98 12V auto and slid the plate almost all the way (adjusted for smoke control). Around 2005, I installed ATS triplelock TC and valve body. Late 2012, the engine finally stripped the splines out of the trans' input shaft. So as good as the 47RE is, it can still be damaged over time by a very moderate power increase. Until the splines got eaten, the truck ran like a raped ape.

You mayn't need billet input, intermediate and output shafts; but you will need to drive sensibly: lift the throttle some just before the TC locks up. And don't hammer the throttle (on/off/on or just off/on) when the TC is locked. Be aware that it doesn't take much extra power to break things and that it can take time for things to break.