2001 Gmc Sierra Problem

[jivens15]

Ok so about 1500 miles ago my tranny went out completely. I had it rebuilt with a TCI Kit that came along with a shift kit. Its done great. The thing is that it used to shift hard into second but now theres barely any shift shock at all, maybe its just broken in? A couple more things, at 45-55 mph my truck while cruising, my truck will rev 200-300 rpm about every second. I've also noticed that a couple of times it will make a loud clanking noise and start studdering while cruising at about 45-55, You can feel it shaking in the floorboards! I ran a scan and i had a fuel pressure sensor code, and my heated 02 sensors are bad. Please anybody help

[jivens15]

also, its a 5.3 liter automatic with 153,xxx

[jayclover]

RPM changes and clanking/studdering...? Sounds the transmission is slipping. I'd take it to whoever did the rebuild to have it checked out...

[Cdale2k]

The Rev jumping at cruise sounds like an o2 sensor, plus with that scan i would probably have them replaced. This has happened on my truck, replaced the o2 sensors and had no problems after that. By the way, what type of exhaust are you running, I have heard that can affect how your o2 sensors work.

[Lincoln30]

I agree. Take it back to the tranny shop.

 

My after rebuild problems were not as bad as you make yours sound...yours sound more like the symptoms before my rebuild. I had some shuddering and clunking at times (not often) after my rebuild but three attempts to get the tranny shop to fix it didn't help (they are idiots). I asked a friend in the know about what to do and he said it's very common to have some debris in the tranny after a rebuild and flush (not just a drain and fill) would be necessary to solve the problem...he was right.