I had my stock cat/o2 sensors/muffler replaced with 2 ntk sensors and magnaflow converter and muffler. I took it out on the highway to see how loud it was and at 70mph i was at 2600 rpms. definitly not what i expected with the new parts and upgrading from a 2.5 to 3" exhaust pipe. Do i need to be concerned something is wrong or do i just need to let the pcm learn the new o2 sensors?

Thanks,

 

How is the exhaust going to have anything to do with rpm? My 2500 with 4:10's hangs around 2200 at 70. Was OD on?

 

Maybe it's not going into OD then. Do you feel it shift?

 

I was positive the exhaust wasnt throwing anything off but i figured the 02 sensors might. The od was on. Its always on atm because the button is broken and i havent fixed it yet.

 

Take it out on a nice, long, straight, stretch of road with minimal traffic, start from a dead stop, and make sure you are getting all four gears, and TCC engage.