Newbie with questions re:1995 5.7

BigWheelinBubba · May 9, 2005

I just bought a 95 2500HD ext. cab 2wd. The problem is has is it has low oil pressure when hot. The gauge falls down to about 13-15psi. I also hear a slight valvetrain tick all the time. Its very faint but noticeable. I bought the truck because it was cheap. I figured worse case scenario i'd have to put a motor in it.

Anyhow can anyone give me some advice? I'm into cars and very skilled mechanically. Can I get away with replacing the oil pump with a high pressure pump or should I get a stock replacement? BTW the engine has 140,000 miles on it and runs great otherwise.

Oh and another question: Are the 95 engines equipped with a roller cam?

Thanks in advance for any help.

Mike

BigWheelinBubba · May 11, 2005

40 views and not one response??

mmmikkke · May 11, 2005

I have a 1995 K3500... Hey, wait a minute. They didn't have a 2500HD in 1995... At least they didn't call it an HD...but I digress.

Anyway, I have 144,000 miles on the truck, and my minimum oil pressure is around 20, usually between 40 and 60 while driving. So that should give you a reference point...Something is worn more than mine, with equal miles. Maybe this truck has worked hard...

Friz · May 11, 2005

At 140k, I'd say that's decent oil pressure at idle. A good rule of thumb is 10 psi oil pressure for every 1000 rpm.

Usually it's not the oil pump that wears out. An oil pump is probably the simplest mechanical device on your truck and it is constantly flooded with oil.

Usually, the crank and/or main bearings start to get a little worn and oil squirts out the side rather than travelling the length of the crank. That's where the pressure loss is.

A slight tick in the valvetrain may be a worn, loose, or sticky lifter.

No rollers, just plain old hydraulic lifters.

With that high mileage, if it runs good but makes a little noise, I say enjoy it until you either want to or have to replace the motor.