The speedy sleeve for the front seal from cummins is a seal kit but the one from a parts house is thin enough that you can use a standard seal. Good thing because I didn't want to buy the seal twice.

 

Dont use the thin one, the seal will eat through it in a week.

 

Will it really? I've already ordered the parts and was going to install them this week.

 

Never put one on a Cummins, but I did use one on my 92 Jeep Cherokee inline 6. I put 110,000 miles on it without problems. I also had 230,000 mile on it when I sold it. I bought it with 120,000 miles.

Its up to you. Personally I try to use Cummins parts, because they arent far from me and are open till midnight. But its your money.

 

I measured everything out and it turns out that the grooves aren't far enough in to cause the seal any problems. They were from when the previous seal was installed and the installation ring was left in there behind the harmonic. It should seal. If it doesn't then I'll buy another seal and put RTV on the timing cover and do away with the gasket and that should for sure get the cover back into good metal, but I think that I'm in the clear.