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Hi everybody, I'm new to the forum and I just bought my first truck with a 460. It's a 1988 Super Duty dump truck. The truck is really nice, 10ft bed that is like new, really, just an all around nice truck that drives good and has zero rust. The motor has plenty of power and runs strong, no knocks, ticks, or any other noises, but on the oil pressure gauge it seems to read low. When first started, the needle goes to about the 'N' or 'O' in the 'Normal' range, but then drops to like half way between the word Normal and the white line on the low pressure side. The motor runs good with no noise so I'm wondering whats up? Should I be concerned? Thanks for the help!
Right now I'm going to put 10w40 in it with some Lucas and if that doesn't help maybe a high volume pump?
My 300 six reads the same way. You really have no idea of what the acuall pressure is until you install a mechanical presure gauge My 460 was getting around 25 psi at idle, and about 65psi on the highway. Has over 80K miles. mechanical is the way too go.
To check oil pressure for sure, install a mechanical gauge. Stock gauges suck for accuracy. To check your trucks stock gauge, with key on, engine off, ground the oil pressure sender terminal on the engine, gauge should read full scale, if it does change sender. If it doesn't, either gauge is bad or insturment voltage regulator behind dash is bad (in the latter usually the temp gauge will read low to).
It's very easy to do. You can either pull your electric sending unit altogether (meaning you'll lose your stock gauge) or you can buy a T and use both the new mechanical gauge and the old stock gauge. The oil pressure port is located at the back of the engine block, on top. If you look between the intake manifold and firewall you should see the sending unit. It simply unscrews. The mechanical gauge should come with adapters that will screw in place of this. Then they'll typically use a plasic hose which you need to run through the firewall to the gauge. Make sure it's tight and secure on both ends, not kinked anywhere and not rubbing on anything. You're good to go.
On a side note: My advice is to throw the plastic hose away and have a local hose shop make you a braided stainless hose instead. It really sucks when the fragile plastic line gets a kink and bursts unexpectedly spraying hot oil all over your legs. My buddy found this out the hard way on his wedding night. The stainless lines can cost more than you'll pay for the gauge but are definitely worth the money in my opinion. If you choose not to go this route then just be very careful to use grommets and check carefully that the plastic line doesn't rub or bend anywhere along the way.