Hello. I'm a newbie. Just got a '77 Dodge sl6 truck. Fabulous rig. I took it out for a high speed run, and at about 55 mph, the oil gauge went down to practically zero. At lower rpm, the pressure came up to about the 35 mark. The oil is fine, full up and clean. Am I looking at a sender unit or a sensor going bad, or something else. Has anyone had this kind of thing happen?

_________________
1977 Dodge Custom 150

Welcome here. Probably a faulty gauge. If the oil pressure had actually dropped off to zero, you would have heard about it (rods knocking, engine self-destructing). The sender is a logical place to start. Also it will also be a good idea to service the oil pressure relief valve to make sure it's doing its job, as described in these two threads: thread 1, thread 2.

_________________
一期一会
Too many people who were born on third base actually believe they've hit a triple.

Thanks for your reply. I'll check the valve as you suggested. I kinda figured if it were really zero pressure, I'd have symptoms, ie dead truck. This is such a cool site-lots of mopar experts!

_________________
1977 Dodge Custom 150