Just purchased a 02 d max after my cummins was totalled since I gave up searching for another cummins amd really dislike dodge trucks anyway. Those cummins guys want to sell there beat up old wore out trucks but still think there the souped up diamond they built years prior before it's life of abuse. Anyways, I was putting in my gauges and was wiring the rail press gauge up and pulled the drivers intercooler tube off the turbo and it has a fairly thick film of dry almost soot like residue inside the tube. What would cause this? Poor filtration ? NeXT step I think I'm going to pull the tubes and IC and do a thorough cleaning. It did not have a filter on it when I bought the truck, I put a nice cone filter on 30 min after buying it. I also have this thud upon taking off, I've changed all the brakes u joints look good no bad bushings in the leafs, the rear shocks are shot. If I take off very slowly it's barely noticeable but taking off normally it feels like somethings very loose. I can't find anything. Ok ok one last question, on the cummins and fords uou open the oil filler and check for blow by, are these duramax the same generally theory? Thank you for the info sorry for the long read, been a cummins/powerstroke guy until now.

 

Do you still get the clunk on take off when doing a mild power brake?

The soot may be from the egr. Is your truck a cali or federal emissions truck?

The lb7's blow by can be checked at the pcv hose running down the passenger side of the engine or the oil fill cap

 

I Dont believe it's a cali truck ? OK when I open the oil cap while running I don't get a ounce of pressure, smoke or any kind of pressure. I'm assuming that's a good thing of its like the other diesels? I am leaning towards the slip joint needin to be cleaned and greased it only appears to do it when the suspension is being compressed or extended. All the u joints are tight and is a one piece shaft. Mounts are good so I think I have it narrowed to the slip joint. I hope anyway. I seen alot of guys say that they traced this problem to the shaft as well so I'll give it a try.