will they fit?

 

I know the 4.8/5.3 y pipes are different then the 6.0. Hope that helps a little bit.

 

I'll add a question to the mix. Does a 5.3 Avalanche use the same Y as a 5.3 Silverado (both '02's)? Remember an AV is on a Suburban frame.

 

how are they differrent?

 

I can't give you an exact answer but I can tell you that my Edelbrock shorty headers said that they fit 4.8, 5.3, and 6.0 but they came with a different header to pipe gasket for one side if they were to be installed on a 6.0.

There is some difference.

 

Mine said the same damn thing...

 

I don't think that factory 6.0 pipe is a y. I'm pretty sure they're true dual to the muffler. That might be why they're set up different.

 

Ha, I just saw that movie...Strokerace

 

I'm not sure about the original question if an 02 y will fit 04-05, but I can explain how the 4.8/5.3 is different than the 6.0. As StrokerAce mentioned, the 6.0 is 2 separate pipes which go to a dual inlet mid pipe/muffler, while the 4.8/5.3 is a y-pipe that goes into a single 2.75" pipe. The exhaust manifolds are also slightly different in the way that one of them attaches to the front pipe. creederado posted up some pics of the different manifolds and pipes a while back when he swapped his factory 5.3 GMC ex-cab exhaust over to 6.0 exhaust into a Magnaflow catback.

 

I agree