What are the causes the oil light to come on ???? My d2 oil light is on, So I replaced the oil pump and housing, and the light is still on! I don't know what to do next. Any help will be welcome. The d2 is a 2002 and has 175,000 miles on it. the engine runs strong.The heads were replaced 15,000 miles ago. The d2 is in need of paint but is a good truck still. I don't want to take it to the junk yard just yet,

 

oil light on and won't go away

 

Oil pressure switch turns light on when it grounds itself

 

probably best to use a mechanical gauge to verify the oil light is coming on for the right (or wrong) reason. it could be the oil pressure switch has failed, there is a short in the wiring, or, even after the oil pump change, you still are not building enough pressure.

if the oil light is correct and you do have low oil pressure, this could be caused by a cam shaft that is beginning to "walk". only fix for that is a new cam shaft, assuming of course the journals are still good.

i had this happen in my '04. cam shaft "walked", which caused low oil pressure. fortunately, the journals were still in good shape. i ended up putting in a Crower Stage 2 cam shaft for the little extra power/hp.

 

Thank you for confirming my worst nightmare. That I need a new engine. Now I need to look for a engine or take it to the junk yard. Dam Dam Dam. I will miss the D2 .Thanks for the info. Dam Dam Dam off to the junk yard I go.

 

The cam doesn't walk, a cam bearing does. Several threads with pics in the forums. I got a truck once and found a cam bearing in the oil pan. Usually caused by an overheat. Can be repaired by installing a new cam bearing. Not super easy. Most shops will tell you it needs a new engine because they won't take on the task of repairing it. Hard to find a shop that will take on that kind of a job.

 

@scubateacher Start simple get the pressure checked, any competent shop should be able to do it. Or buy a new sensor and install it.

You are a long way from it is junk. Camshaft bearings are a pain in the butt on a traditional, But they can be replaced or even re-seated.
If it is the bottom end bearings they are easier
A clogged oil pickup or failed o ring on the pickup can cause issues as well

Also are you running the correct oil weight 0 anything is not recommended, generally 10/30 or 10/40

 

Extinct, you are correct. it is the cam bearing that walks. sorry for the incomplete information. it was the cam bearings that walked on my '04.

 

feels like you're jumping the gun here; unless you have already used a mechanical gauge to measure the oil pressure and not posted that information up.

get more conclusive testing done. as stated by others, any competent shop can test the oil pressure.

 

Please get it diagnosed properly or sell it to someone who wants to fix...these trucks are sweet once the issues are worked out and shouldn't be going to the junkyard. If you want a brand new, solid axle 4x4 you are looking at 70k+ so my logic says its cheaper to rebuild the engine and I did just that when my cam bearing walked.