Hello, i recently brought a 2004 Chevy 2500HD 6.0 gas with automatic trans 4x4. work truck with 200,000 miles on it. I changed the oil and filter and replaced it with 5w30 high milage oil which was recommended. Then i noticed that the oil gauge fluctuates between 20-25 when start and idle but did goes up a little bit when step on gas. Before the oil change it was at 40
Some forums suggest doing a engine flush then drop pan and change the oil pickup O-ring. Some say the oil pressure sensor filter might be clog. Do you think 5w30 was too light, should have gone with 10w30 or 10w40 or 5w30 with Lucas oil stabilizer. Any thought on how to fix?
Thank you.
The previous owner may have used heavy oil to mask a worn engine that has an oil pressure problem. You might want to verify actual oil pressure with a mechanical gauge.
use the oil specified in the owner's manual
