Just quick question. Ive never heard of anyone running the overhead on our CTD's. I know on big trucks youre supposed to set the valves every couple 100K miles. I know that there are alot of this dodges with 200, 300, 400K miles on them out there. Is it ever necessary to run the overhead on these cummins motors, (5.9 or 6.7) ???

Sorry for the double post!

 

Yes. I believe at 100k you are supposed to lash the valves. If that is, what in fact, you mean by "run the overhead"... which is a term I've never heard of and may have thrown a few guys off here.

 

Yes, 100k for running the overhead. However, I've yet to see a truck that was off enough to require adjustment but we run them anyway. The valvetrain in these critters are pretty darn good.

 

Yes that is what I meant by that! Just an old "trucker" term Ive heard my Dad say over the years referring to setting the valves. This was just a topic that came up in conversation between me and some other diesel truck owners, and none of us knew whether you were ever supposed to, or needed to. Thanks for the info though!

 

You should probably run the valves on your truck. I havent checked the 6.7 yet but I know that when I had my 04.5 every valve was out at 36k miles! Most Cummins gurus seem to say set them at 40k miles then every 100k after that. The later adjustments tend to be within spec.