On The Road Again

jn452 · October 9, 2009

I posted a topic about a 3 weeks ago asking for help on my truck and its lack of oil pressure. The basic problem was little to no oil pressure at start up and it would not increase with engine rpm. I have a 2004, 2500 with a 6.0 and a five speed. I was given some helpful hints but it did not seem like anyone else had experanced this specific problem.

Well the truck is fixed now and I just thought that it would be a good thing to describe the problems and what i did to fix it so that in the future this may help others experiencing the same problems I was.

I dropped the oil pan and pulled all the accesories off the front and removed the timing cover to expose the oil pump. The pressure relief valve in the pump was bad. I had planned on replacing it so this was no big problem, however I do not think that it was the leading factor in most of my problems. The pick up tube was bolted right but the tube was not tight to the pump. I could wiggle it back and forth. I ordered a new one from GM because it is still a factory part that you can not get anywere else. When I picked it up i was told by the parts manager that it was a redesign that would bolt tight and not move at all. He told me that GM had had some problems with the oil pumps sucking air because of the original design. I do not know what years this affects but know it does affect the 2004 year model. Now as long as i had everything apart I replaced the timing set and the water pump, fan clutch, belt and tentioners. put every thing back together and it runs great with good oil pressure.

I would highly reccomend replacing your timing set at about 200000 miles because my truck feels like i added about 40 hp and i am getting 16 mpg now when i was getting 13 mpg before. Like i said earlier the truck runs great and the oil pressure is doing exactly what is should.

One thing that I was told that i do not know about and would like your input is this. I was told that the bearing tolerances are so muck tighter on the new engines and specificly the 6.0 that using lucas synthetic additives was bad because it was too thick and would cause problems. I do not know if that is what caused my problems but i did not put it back in my oil when i refilled the engine. I do not know but I think that i will stay away from it and just use straight royal purple 10w 30 from now on.

dewfpo · October 9, 2009

I posted a topic about a 3 weeks ago asking for help on my truck and its lack of oil pressure. The basic problem was little to no oil pressure at start up and it would not increase with engine rpm. I have a 2004, 2500 with a 6.0 and a five speed. I was given some helpful hints but it did not seem like anyone else had experanced this specific problem.

Well the truck is fixed now and I just thought that it would be a good thing to describe the problems and what i did to fix it so that in the future this may help others experiencing the same problems I was.

I dropped the oil pan and pulled all the accesories off the front and removed the timing cover to expose the oil pump. The pressure relief valve in the pump was bad. I had planned on replacing it so this was no big problem, however I do not think that it was the leading factor in most of my problems. The pick up tube was bolted right but the tube was not tight to the pump. I could wiggle it back and forth. I ordered a new one from GM because it is still a factory part that you can not get anywere else. When I picked it up i was told by the parts manager that it was a redesign that would bolt tight and not move at all. He told me that GM had had some problems with the oil pumps sucking air because of the original design. I do not know what years this affects but know it does affect the 2004 year model. Now as long as i had everything apart I replaced the timing set and the water pump, fan clutch, belt and tentioners. put every thing back together and it runs great with good oil pressure.

I would highly reccomend replacing your timing set at about 200000 miles because my truck feels like i added about 40 hp and i am getting 16 mpg now when i was getting 13 mpg before. Like i said earlier the truck runs great and the oil pressure is doing exactly what is should.

One thing that I was told that i do not know about and would like your input is this. I was told that the bearing tolerances are so muck tighter on the new engines and specificly the 6.0 that using lucas synthetic additives was bad because it was too thick and would cause problems. I do not know if that is what caused my problems but i did not put it back in my oil when i refilled the engine. I do not know but I think that i will stay away from it and just use straight royal purple 10w 30 from now on.

Thanks for letting us know how you fixed your oil pressure problem.

I too have heard from many sources that all of the modern engines are manufactured to such better tolerances than they were in the 80's that there is no need and they DO NOT recommend any oil additives of any type. The oils we use today are so much better than they were in the 70's and 80's as well (and have been upgraded several times since then) but habits are hard to break for some folks. Just like 3K oil changes. I was never able to convince my dad otherwise. But then, when he was growing up, oil came in open top glass jars and you bought them at the gas station.

DEWFPO