Well, now that my truck has a whopping 200,000 miles on it, I'm due for my second Cummins recommended overhead. I understand the reasons for it, and have seen what happens when a Cummins never gets overheads, but I am hesitating. The reason I am hesitating is because I am getting the best fuel mileage out of my truck that I have ever gotten. I'm currently averaging 6.19 mpg, and have had some trips average over 7 mpg. It is a virtual guarantee that my mpg will drop after the overhead, and how long it will take to go back up is anyone's guess.

Part of me is saying that I need to get it done, because it is a preventative maintenance item, but another part of me is saying "If it ain't broke, don't fix it". What say you, all the CAD experts?

 

Just set the truck on fire and collect the insurance. We all know it's only a matter of time anyway.

 

When I had my first one done at 110K, I noticed a definite mpg drop. I honestly don't remember when it started to go back up. All I know is that I started getting 6+ mpg about 30,000 miles ago, and I hate to ruin a good thing. But I know that the overheads are important, especially on Cummins.

 

I just had my C-15 done. Last one was 113,000 miles ago....they told me yesterday to get it done sooner...suggested 65,000. All but 1 injector were out of wack..and 4 exhaust valves as well.

 

When I brought mine in the service manager asked why, did your MPG drop? I said no and he said I shouldn't have it done. I wanted it done anyways and everything was perfect except for the jake spring which was broken.

 

Cummins are much different. If you don't get them done, you can get valve slap against the pistons, causing wear on the crankshaft.

 

I have an acquaintence in Las Vegas that does insurance adjustments on Commercial equipment. He was telling me the other day about the surge in "Fires Of Mysterious Origin" reports he is handling lately.

He says even the trucks that are salvagable/repairable are going for half of what he could have gotten a year ago.

I told him to find me one so I can start out on the cheap. He has a nice car hauler, but I have never hauled cars before. The trailer was bent up but the tractor is good.

 

I have one friend who doesn't an overhead every year, regardless of the miles. I would do what the manufacturer suggests. After all, they built it. :wink:

 

I've already decided to do it. I'm curious if it will affect my mpg this time.