Got a set of stacks on my truck and I love the way they look, just hate all the noise they make when towing. Have any or do any of you guys run the internal mufflers that grand rock has, and do they quiet them up any. thanks.

 

Anybody????

 

I thought about trying them...but I bought a Donaldson 51" muffler instead cause it was only $76 bucks shipped

 

I tried the drop in mufflers from GR and they are totally useless. They didn't make the least amount of difference. I haven't tried the QP style,they cost too much and would have to be cut to length. A muffler is going to be the only way to quiet them down.I have ordered a diamond eye and will be putting it on when it arrives.I have the cat on with no guts in it and it limits the length of muffler you can run.I don't want to remove the cat body for inspection reasons.Still trying to find a muffler that wiil eliminate the drone but fit the space I have available.

 

yea the drone is def killer, i love the sound but not the drone

 

yea i got the internal mufflers and they ARE useless 80 fricking bucks i cant get back

 

I got tired of the drone in my truck at certain speeds also. I'm going to be putting a 5" magna-flow muffler with 5" downpipe back. I'm hoping it gets rid of the drone.

 

A suggestion to check into is there are big truck mufflers that have the in on the end and the out on the side of the muffler. If you look under some of the large ryder/penske box trucks, they use this style. Don't know how quiet or restrictive it would be.

just a thought

 

I had thught about that as well.How restrictive are they is the big concern.These larger diplacement diesels have got to be able to move some volume I would think.

 

i used a 51" donaldson with my stack and have no drone, i have enough room to reinstall the cat as well if i ever need to

there is always the option of the 40" donalson too.....

 

How would you be able to cram all that under the truck?(cat and 51" muffler)I barely got the 27" diamond eye to fit with the cat in place.The cat is cut 4" behind the body(just enough to slide the muffler on) and I still had to do some custom cuts on the muffler to make it fit.