Hey everyone, i have a 2007 Chevy Silverado Classic LS crew cab that is having some problems with the TCC, or at least i think it is. I recently had dual exhaust put on it, (dumps with flowmaster 40's), and naturally its louder, well when i get to about 43-45mph the TCC will engage, but my RPM's fluctuate, and not like other posts ive seen where you can notice the RPM gauge jumping. It fluctuates slightly and i can hear it in the exhaust very obviously. When it reaches about 55mph it will smooth out and sounds great. I know it has to do with the TCC because if i mash the brake and disengage it, it doesn't fluctuate. It seems to do it just in the initial engage 45mph zone. I never noticed it before with the stock exhaust, but then again i couldnt hear it since it was quiet. Is there something i could do? its still under warranty, but im not sure if the exhaust might have messed with something. The pipes are stock past the cats and then the custom exhaust starts. Im not sure what my options are. maybe the PCM needs a tune to increase the TCC engage speed? oh and the engine is a 4.8L vortec. not sure what the tranny is. It just bugs me when im in town going 45 and it surges.