I was thinking of rebuilding my engine which only has 105,000 miles which is not much for these engine. The thing is I didn't put those miles on this truck and I know it was run hard and was not kept up right. So with that being said I would like to upgrade rotating assembly and keep it reliable due to being in the Hot Shot business.
I see that Ross & and Mahle have a set for the 5.9. Which one of these pistons would you all pick and which pins and rings should I use? How much can I bore over stock or should I keep the same bore size? Now for the rods where can I find a forged or billet rod? Any info would be great thanks. Happy New Year everyone!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!

 

I've done just what you want to do and this is what i found.

Unless you plan to build strictly a race truck, you don't want to use aftermarket pistons. They're too soft/light and won't stand up to extended mileage. You'll be rebuilding before you know it, not that they aren't some sweet slugs.

Standard Cummins pistons are what's recommended as they're some of the best out there. You can shave them to gain lower compression which can benefit.

Same thing with the rods. Unless you plan on 1500hp, it's not necessary. You can get shot peened Cummins rods that will handle plenty for not much more than a stock rod costs.

as for boring... the Cummins block can only be bored twice and can only have a max of .0040" taken out. That's pushing it pretty thin though. .0020" over is a good place to be if that's what you want to do.

IMO, if you want another 100K out of it... you should probably just put everything back to stock specs. You can do other things to gain mileage and power.

 

Cunningham rods is what will go in my truck.

 

tritont thanks for the info. Are there any .0020 over bore stock pistons?

 

well, if you have no damage, the cylinders shouldn't need to be bored and you can go back with stock size pistons. If you do need to bored it, you still use stock pistons and the gap is taken care of with the correct sized rings.

I don't know whether Cummins sells different sizes pistons or not.

 

you can im pretty sure get it bored out and get sleeves dropped in. everytime u redo the engine you just drop in new sleeves and pistins then. might cost more but if you keep truck long enough its a option.

 

These engines don't have sleeves.

 

your right, but they can be sleeved. As for the rods, I would leave the stockers alone. And yes, .020" is what cummins considers .5 mm.

 

They can be sleeved but it's not the "wet sleeve" that larger (semi) engines use that are made to be replaced . The sleeve you use in these engines are "salvage sleeves" that are pressed in block that has been machined for them. Those are not meant to be replaced and are real thin.

 

no they arent sleeved i know. I heard you can get a dry sleeve put in its place. and it wouldnt need to be PRESSES in. You can hit them in with a block of wood / sledge or dead blow hammer. I put dry sleeves in mack 300 engines about 10 times already. They are thin but guess what. they are easily replaced once they go and they last a long time. The costly thing would be getting the **** engine block machined for them. Youd have to remove engine for that.

 

with only 105,000 miles I would run it 200,000 more then think about a stock rebuild or get a new truck. hot shotting is cool, just dump your truck every 300k or 5 years and get a new one. you will save $ in the end.

 

In at work we have had a couple of 5.9 Cummins and C7 Cat engines machined for sleeves. It is for repairing a damaged cylinder and is not meant to be removed and replaced as a wear item. They cut a lot of meat from the cylinder and put in a universal liner. The liner looks like it is 1/2in. thick. They then bore the repaired cylinder to the correct size and center the hole in the block. The machine shop we use at work will not reline an already repaired cylinder.

 

anyways at 105000 miles u r crazy to even think of rebuild. i wouldnt worry until about 700-800000 km.

 

I am thinking of just honing the block, mill the pistons, drop in a new set of rings, shot peened the rods and install ARP rod bolts if they have them. I don't have to worry about the machining process due to have access to a machine shop. When I am not Hot Shoting my real profession is a Machinist. I graduated from School of Automotive Machinist (SAM) 4 years ago but only worked on gas engines. Although now diesels are on the menu. I have a 1970 C10 that I will be placing a modified 6.6 Duramax. I am also considering porting and oringing the cylinder head. From what I can see on the head I would have to mill the intake of in order to port the head properly. As for the intake I could have my buddy Beck who builds sheet metal intakes for pro stock and other organizations build me one.

 

If I won the lottery, I'd go to SAM just because they are supposed to be an excellent school... and that would be my hobby. Heard nothing but GREAT things about them... lucky sob....