My valve adjustment is way overdue, and besides my #6 cylinder valve cover has been leaking for a while....so.....
I ordered a valve cover set from ebay Gen-u-wine Cummins!(GREAT price) about a year ago. Ok....maybe 2 or 3.....Dont be judgmental.
I didnt open the box until this past Thursday. (MY fault!)
6 nice new valve cover gaskets
and 6 I dont know what the eff theyre for gasket/grommet things. 
Theyre part # 3935449
Google says they're isolators for ?....I have no idea. :/
No problem...or so I think...I'll call Cummins.
couple hours later.....
Apparently nobody in this state has a parts stock.
Had to cross reference a Federal mogul part # through NAPA. They come in packs of 20......
.....OK. I dont mind having parts I can actually use. Besides Cummins wants something like $3~ish ea, and I can get a pack of 20 for $20. Yea! 
Ordered on Thursday, said they'd be here Saturday morning.
Guess what? THEY DIDNT SHOW!



Now I'm getting pretty angry. My truck has been apart since Thursday.
Back to google. I re confirmed. Nobody in the state (Marine dealers, off road equipment, generator places, etc.etc.etc.) has any of these in stock.
I finally found a NAPA that has an O ring assortment.
WOW, a "dorman" for O rings. Must be a mirage. I have to go see this myself.
YEA! They DO have one, and an O ring that looks like it'll work!
It's part # 727-2606 a grand total of .63 cents each! The specification on the o ring is 10x2.0. I guess that's metric.
15 minutes later I'm up and running.
This is a public service announcement.:-laf
I ordered a valve cover set from ebay Gen-u-wine Cummins!(GREAT price) about a year ago. Ok....maybe 2 or 3.....Dont be judgmental.

I didnt open the box until this past Thursday. (MY fault!)
6 nice new valve cover gaskets


Theyre part # 3935449

No problem...or so I think...I'll call Cummins.

couple hours later.....
Apparently nobody in this state has a parts stock.

Had to cross reference a Federal mogul part # through NAPA. They come in packs of 20......


Ordered on Thursday, said they'd be here Saturday morning.
Guess what? THEY DIDNT SHOW!




Now I'm getting pretty angry. My truck has been apart since Thursday.
Back to google. I re confirmed. Nobody in the state (Marine dealers, off road equipment, generator places, etc.etc.etc.) has any of these in stock.
I finally found a NAPA that has an O ring assortment.
WOW, a "dorman" for O rings. Must be a mirage. I have to go see this myself.
YEA! They DO have one, and an O ring that looks like it'll work!

It's part # 727-2606 a grand total of .63 cents each! The specification on the o ring is 10x2.0. I guess that's metric.
15 minutes later I'm up and running.
This is a public service announcement.:-laf