I have a 2001 2500 cummins with a flat bed. I want to put duals on it instead of the single wheels. I have tried a set off of a 99 3500 but the rims hit the rotors on the brakes. I am assuming the 3500's have drums in the rear and the 2500's have discs and this is why they wouldnt fit. Any suggestions would be appreciated. Thanks.

 

If you do indeed have rear disc brakes I think you need at least a 17" wheel to fit...

 

And here I thought this was another exhaust post.

OP, sorry, I can't help ya. Haven't a clue.

 

Welcome to DF! I don't know much about dually's, but would you not need the whole axle from a dually truck to fit dually wheels?

 

I believe the 3500 axles were narrower as well, were they not?

 

You need a conversion kit

http://www.arrowcraft.com/products.php#kits

 

Maybe something as simple as wheel spacers? (Although personally I'm not a fan as it pushes the weight distribution out further on the lugs)