I had problems with my 2005 LLY sticking in fourth gear when passing on the highway. I kept getting a TCM fault. I took it in to the dealership since it is under warranty and they cleared the code. I had to do this three times. Then one day I installed the tow tune and my programmer starting ...

[quote="hayoda"]When I purchased the Diablo Predator for my 2005 GMC 2500 HD Diesel I was pleased with the performnce and increased gas milage. Well that changed after a while and I started having problems with my transmission dropping into 4th gear and sticking there. When it happend the first time ...

When I purchased the Diablo Predator for my 2005 GMC 2500 HD Diesel I was pleased with the performnce and increased gas milage. Well that changed after a while and I started having problems with my transmission dropping into 4th gear and sticking there. When it happend the first time I was on the ...