jday47

i recently cut my exhaust off completly right after the Y after the cats and i put on a thrush welded muffler with a 45 point out with a tip and its dumping out the side but it isnt actually sticking out the side the truck, anyway since id did this i lost about 2mpg but i do like the sound of it very low rumble i was just wondering if anyone had any recommendations on what is a good sounding exhaust that wont kill my gas mileage

My03fx4

Are you sure that its not just because your driving more aggressively, because you like the sound?

OTG02

Hehe that's why my mileage went down. Liked the sound LOLol.

My03fx4

Mine too after I installed my headers. Lol

jday47

no because i hqve purposly been driving like a grama the lastt 2 weeks and im only gettin 16mpg and before i was getting 18. at first when i did my exhaust i was drivin ape **** crazy and gettin 15 lol

A'den Kyramud

Mine did the same thing mate, I went from stock to a flowmaster44 dumping in front of the passenger wheel (3.5" with a 4" tip), and I lost about 1mpg. Mine's a 4.2L as well.

bdtaylor1979

Don't know if its true or not, but I heard somewhere that if you cut the exhaust short or put on too big diameter pipe it will affect back pressure and could affect performance/mpg's. Just something I heard somewhere.

I have a spectre stock style replacement filter, all 4 original cats and a magnaflow 11236 muffler with dual exhaust straight out the back and get 17-18 mpg's with mostly in town driving.