Will it hurt my truck to run no mufflers I looked under my truck yesterday and there is no mufflers at all.

 

nope not a bit. looks like the prior person removed it. is your exhaust a full 4" exhaust or just a replacement piece for the muffler?

 

It is a full dual exhaust but only measures 2 3/4 from the down pipe back. It is not very loud which I find surprising until you get on it then it can get loud.

 

I have a 4" turbo back single muffler and I recently removed the huge resonator (it's about 2 feet long and 8 inches in diameter). I made the exhaust come out before the right rear wheel so it wouldn't interfere with my spare tire. Now the truck gets a loud and annoying harmonic going on from about 1500-1900rpm. It's fine when I get faster, but it looks like no straight pipe for me. Time to put the resonator back on to de-resonate....