Is it possible to leave the heads on and replace the rings through the bottom? My truck uses a lot of oil, close to a quart every 200 miles or so. It has good oil pressure and no noises so I want to pull the pistons out and put new bearings and rings in without taking the heads off as I believe they have been changed recently.

 

I don't think you can get them all out thru the bottom..... Plus, you would need to drop the crank, not something that can be done with the engine still attached to the trans.....

 

How about doing a compression test to make sure? The valve seals could be the problem here. Valve covers can leak a lot of oil also.

 

I will be pulling the engine and crank. Just want to avoid taking the heads off

 

Its not leaking. It's using. Valve cover gaskets are new. Compression is low. I haven't checked it but it can't hold itself on a hill.

 

Do a leakdown test. (requires an air compressor, and gauge set) That will tell you what kind of shape the motor is in, and where the problem is. (you'll be able to hear the air escaping, and where it is going.)

 

I will be doing a compression test this weekend just to confirm, but since it can't hold itself on an incline I'm pretty confident that the compression will be low. I'll also do a leakdown.

 

You are likely correct, but, having the RIGHT answer to where your compression is going will save you a lot of heartache. And probably a few bucks having to redo stuff as well. The heads on these engines are notorious for cracking around the valve seats, and if run like that long enough, will actually burn away the valve seat.... so, low compression.....

 

I believe the heads have been replaced. When I was doing my plenum gasket there was 3-15 wrote on both heads. When I changed the valve cover gaskets I didn't see anything obviously wrong with the heads. But like I said I will be checking this weekend.

 

Let us know what ya find out.