TCC Shutter

Anyone having trouble with Torque Converter Clutch Shutter in their 2500 Avalanche? I bought mine used with 21000 miles on it and it runs great. The 8100 motor is strong. Back to the question. I have had it at the dealer several times, they can feel the shutter between 45 & 60 under slight load conditions. There checks says it has too much exhaust back pressure. Truck came with a flowmaster and dual exhaust, too loud for me, so I had a stock muffler and single exhaust put back on it. This did not help the problem though. I have mention to the dealer that the exhaust has nothing to do with it, but they will not replace the converter. Anyone else having this problem. Thanks.

power programmer or dealer ecm reprogram

A new computer was installed and programmed and it is still doing it. I even bought a HyperTech programmer and changed the shift points and shift firmness and still getting the same TCC shutter. Someone told me to have the trans flushed and use a cleaner. Haven't done this yet. Will have a fluid exchange done when I do it. But have my doubts that this will fix it. Looks like it is going to need a new Torq Converter.

they tryed tellin you that it was because of backpressure issues? wtf lol pm me their number my i know the 8th best tranny builder here in san antonio tx for aamco give me that dealers number and etc and ill have my friend call them up and give them a ear full lol jk, but really you should call the tranny places around you and tell them what the dealer is telling you because thats bs, anyone knows that the shutter is a common problem in chevy tranys well the torq converters