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Camshaft bearings

My low oil pressure in my 2001 jeep grand cherokee I am told might be due to bad cam bearings. If so, what would be an estimated cost of having them replaced?

Which engine? Miles? I’m wondering how one diagnoses ‘bad cam bearings’, as opposed to main and rod bearings…

The jeep, a 4.0 6cyl. with 95000 miles. Spent 600 for oil pump replacement. Not the problem. When i give it gas, oil pressure increases. Has just started making noises like maybe a lifter.

You need to find someone else to look at the vehicle for starters.
Camshafts do not run on bearings; they run on bushings in SOME cases. Cam in block will have bushings and overhead camshaft engines often run the cam strictly on the surface of the cylinder head with no bushings involved.

Put simply, any replacement of an oil pump to cure a low oil pressure problem is a sign of wild guessing.
The oil pump is the first thing to see any oil. If one is going to use the logic that the pump is worn out then it stands to reason that any part that comes after the pump will be worn even worse. In a nutshell, the engine is gone or going.

Texases has the correct point; worn main and rod bearings.
If someone is going to go to the effort to drop the pan and replace the pump then why not drop a few bearings caps while they’re in there and take a look at the main/rod bearings? That would only take a couple of minutes and could answer the question.

For what it’s worth, being a tech of about 35 years or so I can say that I’ve yet to see a worn out oil pump. Maybe some day.

Low pressure according to your dash gauge? It would be good to verify whatever you are using against another temporarily installed gauge. Lifters can be troublesome with good oil pressure.

Bearings in the air cooled VW’s for camshafts.But cam bearings are down the list for the cause of the OP’s oil issues.

Thanks for the reminder on that one. I had forgotten all about the old air cools having bushings.

You know, there’s a mechanic I know (now deceased) who was a great guy and a good tech along with being a whale of a car customizer.
He used to mess around with a lot of Ford and Chevy engines and whenever there was a problem with low oil pressure, oil light flickering at idle, etc. he always reverted to an oil pump fix.

It never failed that he would replace the pump first and if that didn’t cure it then it was back off with the pan and throw a set of bearings in it.
Depending on the crank journals sometimes this worked and sometimes it didn’t. It always amazed me that an oil pump is the first suspect whenever a problem like this exists.