On PSD's we use the 6637, but I see you guys talking about all kinds of other filters. So which is the best to use that bolts right in?

 

mine at napa was a 2790.

 

Ya I was seeing the 2790. Is that better than the 6637, or is that just the proper fit for the cummins?

 

thats just the right fit, your stock intake tube will fit right over it. its a reeeeaaaaalllllllyyyyy big filter tho haha. its fun to pop the hood have people go WHAT THE HELL IS THAT???

 

X2 ^^^^ and yep they fit right over the intake tube real nice.

 

^oh bad-*** guys! So I dont need a piece of exhaust piping or pcv or anything? The 2790 will clamp right to the intake tract?

 

yes, mount the filter on a chunk of exhaust tubing, pvc, or abs. If you mount the filter directly the the tube it can come off, letting unfiltered air in.

 

What size pcv should I use? 4" od or id?

 

measure the insside of your filter

 

I never had a 2790 BHAF come off the stock inlet tube on my '97...not in 3 years of daily driving. I had one pop off the tube on my ol 1st gen CTD and it sucked a rag laying in the fenderwell up through the turbo...BOOM!

Wix & Napa Filters & Accessories: FleetFilter Secure Online Store #42790 is only like $44. I buy all my filters from them.