can i just go to my local napa and get a rear main seal. or is it that much better to drive an hour to the cummins store to get the seal kit for tomorrow night?

 

i m in the same situation, i have to dive 1.5hrs to pick up cummins parts but for something like a rear main seal I think its worth it.

 

The cummins seals are worth the time and money. I believe they are teflon impregnated as the other brands are just neoprene or some such. If it was an easy seal to get to I would say yes go with a cheapy if you must, but what costs more, the effort to get a real cummins seal or doing the job twice?? Just did my rear main when I rebuilt the auto tranny and the seal kit was about $65 or so IIRC.

 

I wish we had thought ahead and got a cummins seal instead of the leaking napa seal I now have....

 

I have read the stickie and what are good # front and rear seals?

 

These are the seal kit numbers. The kit includes the seal, a metal intallation ring, and a plastic protective sleeve to slide the seal over the end of the crank. Front #3937111 $32.95. Rear #3934486 $69.55. The big secret with these seals is that they must be installed dry. No oil!!! just squeaky clean with brake cleaner on the crank surface.

 

If your crank shaft is badly groved Cummins has a repair kit that has a oversize seal and a sleave for the shaft.ken

 

I just put in a NAPA seal because the Cummins one I got was damaged before it was in my possesion. Looking at them side by side there was absolutely no difference except color and the fact that the NAPA one didn't say Cummins on it. This was the front seal.

 

Cummins quoted me $92.50 for the rear kit last night. I ordered it so i can just get my truck back on the road asap.

P/N # for the rear he gave me was #3934486

 

make sure you check your crank surface before you order too...i just ordered one before i looked and my crank surface is badly grooved, i tried seating it at a different depth but it started leaking already! and i took my time