Guys, I was in Detroit this weekend and the car was absolutely fine the whole time we were there even up until the morning that we were leaving. So we get on the highway to come back home to Grand Rapids and I noticed that my oil pressure was only reading about 30-32 psi at 75-85mph. So I 2-wayed my buddy in the lead and told him that we needed to hit the next exit and check out the problem. We get to the gas station and notice that at idle the oil pressure only reads about 10 psi. Now remember, this is what the guage was saying. So I pull the dipstick and its about 1.5 quarts low... strange, but my rear main appears to have bitten the dust so maybe it leaked that much on the 300-400 miles we drove that weekend. SI buy a few quarts of oil and add it to the motor and I get the idle psi up to about 15. Get back on the highway and drive all the way back home (150 miles) and it sat steady at about 34psi. Well... now when I get to a stop light it falls all the way to 0psi. Now, I am not certain if its just the sending unit because even at 0 psi the motor idles perfectly normal. Never misses a beat, power is all there just like normal.

Any opinions? Could the block be cracked? I have heard that a cracked block can sometimes never appear to have any problems in the performance of the car.... what do I do?

 

My 350TPI always read real low pressure its right below 30lbs at 65mph and when it idles its on redline but i do have 204K miles and its never been rebuilt...my car has never had a performance problem either so i figure as long as she runs good and doesnt miss or anything she must be good to go...

 

Mine does the same thing as well, floats at the redline when warm at an idle. I wouldnt trust the stock guage as far as I could throw it...I think the Haynes Manual I have says that minimum oil pressure is 20 lbs at 2000 rpm, or something like that. As long as you have pressure above idle, everything should be fine.