99 yukon exhaust

[redwood logger]

So forgive my ignorance but my 99 Yukon (California rig) obviously has an aftermarket Muffler because it says MagnaFlow on it but I'm not sure about the rest of it. it has two small welded in catalytic converter looking things one on each pipe before the pipe turns into one and heads for the muffler is this the stock setup? If so what are the odds that these could be plugged up? It runs good but doesn't seem to have the power it should have with the 5.7 engine. And it has blown its second donut at the Joint between the manifold and pipe

 

[GoToGuy]

99 California GM has twin cats. Having leaking exhaust can affect tune and power. Still have poppet injection or upgraded?

 

[Schurkey]

it has two small welded in catalytic converter looking things one on each pipe before the pipe turns into one and heads for the muffler

The service manual will have exhaust illustrations to confirm. At least, the '97 manual does.

Far as I know, GM used a muffler with dual inlets, not a "Y" pipe and a single-inlet muffler.

I don't think that's stock. But I did install a "Y" on my exhaust, and a single-inlet muffler. So I bet my exhaust looks much like yours.

 

[L31MaxExpress]

The service manual will have exhaust illustrations to confirm. At least, the '97 manual does.

Far as I know, GM used a muffler with dual inlets, not a "Y" pipe and a single-inlet muffler.

I don't think that's stock. But I did install a "Y" on my exhaust, and a single-inlet muffler. So I bet my exhaust looks much like yours.

Some if not all of the 5.7L 2 door Tahoe/Yukons as well as the later vans in the 2000s had dual cats into a Y-pipe into a single muffler from GM.