Darin M.

I recently bought a '91 LX 5.0 with 94,000 miles. The car is totally stock and runs great (besides being slow).
I noticed that the oil pressure is low when I first start it and very low (almost in the red) when hot. It has had regular maintainence since at least 2001. The oil in it now is 10-40.
I've had a few 5.0s and this one is the only one that worries me with the oil pressure. What could it be? Should I go with a 20-50 oil or try something else?

Thanks,
Darin

WhiteWindsor

A thicker oil might put a band aid on it but wont solve the problem. I would do a compression check and get another gauge, they are notorious for not reading correctly. Do a compression check and see what you have. Are you burning or losing oil anywhere?

WhiteWindsor

forgot to add, it could be internal. But at least withthese simple steps you can rule them out.

PRO50SC

The first thing I would do is screw in a mechanical gauge and check it. It might just be a faulty sending unit. Look at the simple things first.

Darin M.

No smoke, no drips, clean oil and coolant. It's actually very smooth. I'm hoping it's the sending unit like Pro50 said.

VaRust

Thats what was wrong with mine.

mjr46

exactly^^^^^^^^^...no need for compression checks until you can verify the functionality of the gauge and or sending unit..first things first.....like pro says if the mechan reading confirms a low pressure issue too..then it's internal but if not...it's a sending unit or gauge issue..most likely a sending unit