while i was getting my new truck ready for inspection, i noticed the exhaust on these newer trucks has a small resonator just before the cat. my question is how restrictive is this? If i cut it off and just put a piece of pipe in its place, would it affect anything like the O2 sensor readings?

while i was getting my new truck ready for inspection, i noticed the exhaust on these newer trucks has a small resonator just before the cat. my question is how restrictive is this? If i cut it off and just put a piece of pipe in its place, would it affect anything like the O2 sensor readings?

That is a new twist on things. I have not run nto it.
Could it be a pre cat?
Any 02 sensors befor or after it.
What engine and transmission?
MT

That is a new twist on things. I have not run nto it.
Could it be a pre cat?
Any 02 sensors befor or after it.
What engine and transmission?
MT
yea other people have mentioned a resonator on the new trucks so i guess that is it. its a small canister about 5-6in long at the bottom of the y-pipe before the cat. engine is the 4.3 vortec csfi w/ auto trans. there is 1 O2 in the y-pipe on the drivers side and 1 O2 after it but before the cat.

yea other people have mentioned a resonator on the new trucks so i guess that is it. its a small canister about 5-6in long at the bottom of the y-pipe before the cat. engine is the 4.3 vortec csfi w/ auto trans. there is 1 O2 in the y-pipe on the drivers side and 1 O2 after it but before the cat.

I am not real sure about it but it maybe a pre\small cat.
You might check the parts book and see what it says about it.
Unless you have to much back preasure I would not replace it.
If you find out for sure what it is let us know.
Good Luck
MT