What is the difference between the 51" Donaldson with the 4inch inlet/outlet with a 10" diameter and the 51" Donaldson with the 4inch inlet/outlet with a 9" diameter? Which one should i order?
Thanks Andrew

 

Hey there I have been through the muffler thing trying a magna-flo and a small bullet type muffler they both sucked.I now have a 51 Donaldson and I think its perfect I have a 06 short bed quad cab and the muffler fit fine in the stock location just cut some pipe off towards the front side of truck and it fit right in added a couple of hangers and its good to go.

 

I have the 40" Donaldson, should be louder than the 51. Got it for about $65 from ryder fleet products. No drone while towing my horse trailer. Model no M085171.

 

alMout does the 40" have both 4" inlet and outlet on center? As the 51" might be to quiet for me.
Thanks Andrew

 

It has 4" in and out, cross references to my 86127 Nelson as shown here:

http://www.cumminsfiltration.com/pdf...s/LT32002D.pdf

 

Yes, 4" in, 4" out on center, no baffles and a built in resonator. You will need a 4" to 3.5" adapter if you still have the stock 3.5" exhaust.

 

If you like a mild note and lots of turbo whistle through the exhaust, go with a Walker 4'' straight through muffler.. I bought mine from NAPA. I believe the model number is 21471..

 

Thanks for the help. Fisherguy you don't have any drone with the 40" Donaldson either right?

 

No drone, it's still not real loud either, most people can't hear the difference compared to stock. A nice low tone to it without being obnoxious.

I had to make up an off set for it, they used 2 - 45º bends in front of the muffler so the tail pipe angle isn't all whacky.
You can get the bends at Cummins too, or NAPA etc, or use a 'muffler delete' pipe.
Pics in my gallery, you'll see what I mean.
You use an offset Almout?