I am in the process of building a truck -12 valve-. While I have the engine out would it be a good idea to change the bearings? 195,000 miles on it and to my knowledge has been well taken care of.

 

I'm interested too. I've got 203,000 miles on mine, but it still runs great and has good oil pressure.

I read somewhere that Cummins suggests new rod bearings be installed at 300,000 miles. Anybody know for sure?

 

If you have it out replace them its a lot easier to do it now and they don't cost that much. There is only one crank thrust and they do get loose.

 

At 200,000 I dont think you will see much wear....however if the engine is going to be out, I would consider rod,mains and all new gaskets. OEM parts only.