Okay I have a 1999 Chevrolet Silverado. Just recently I have heard a ticking sound sometimes when I'm accelerating but then it will go away. Today I noticed that when that ticking sound was going that the oil pressure gauge would be almost at 0 and then it would pop back up to normal and the ticking sound would go away.

I have no idea where to start on troubleshooting this problem so what do you guys think it is?

 

Sounds like an oil pump system issue to me. I wouldn't even drive it until the problem is repaired, Could cost lots of $$ if you do. The ticking sound is likely your lifters not getting oil.

 

See that's what I thought. For example, a car running low on oil you hear that ticking sometimes, but typically it doesn't go away. This comes and goes and again, just started. It's parked for now.

240K on the engine mileage wise. I assume that the pump is inside the oil pan? Trying to find a schematic. It's a 5.7 V8.

 

When is the last time you changed the oil and filter? Have you checked the oil level?

 

Oil level is good, and it wasn't dirty.

 

I would remove the oil pan and check for sludge and check the oil pickup for the pump. If it all looks good, I would install a new oil pump since I am already in there.

 

There is a pressure regulating valve in the oil pump assy. Sometimes they get something stuck in them or need to have uneven surfaces smooth out. Would be easier to check that out before diving into a new pump although you still might need to replace the pump body assy.

 

I had a guy at work who works on engines as a hobby. Said that maybe I should also try a thicker oil, like a Rotella T, but seems like if the pump is having problems with factory recommended oil, then it really would have an issue with thicker or heavier weight. Am I wrong in this line of thinking?

 

I would check the exhaust manifolds for loose or missing fasteners. Also, check to make sure there are not any cracks in the manifold.

 

Will do.

I'm also thinking of revisiting the oil. After some research tonight, suggestion is to diagnose the issue and eliminate other things. All of these are good suggestions and I intend to check them out.

As for the oil, I'm going to drain it, take the filter off and cut it open and look inside. If I see a lot of sludge, I'm guessing that is going to be a source of low oil pressure.

Something to note: This is primarily used as a farm truck, so not a daily driver. Since I got it, I have not changed the oil, but I haven't driven it much. Maybe start with the basics?