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Message: [QUOTE="MAFoElffen, post: 957389, member: 14847"] Sort of and sort of not... That is what you you see in a gaser. I checked several Ford tech refrences. 3 sources. The Ford first had is at these ranges, tested at different RPM's: The second said the normal operating specs at operating temp: at curb idle, 10psi; at 3300 rpm, 40-70psi. The third said the minimum is 10psi, but it didn't say at what RPM. The fourth reference was someone who changed their LOP because the pressure was 5-7 psi at idle. Then installed a mechanical gauge at the same time to keep better track of it. He said when it's real cold, it'll idle at 60 psi, but normal operating temp and his pressure is still only 15-20psi. So... If it's 10 psi at 700 rpm normal operating temp and the idle drops to 500 rpm... Does tha mean 7 psi might be normal for 500 rpm? <-- That is a questions that comes from logic looking at those numbers. For me, I would think by logic, volume is more important than pressure in the low pressure oil in these motors. I would think 5 psi is low for even a 7.3l. The only physical measurement checks are done with the pump out, but if you have it out already, you might as well replace it with a Melling high volume pump while it's out. They are not hard to change. Symptoms of a bad LOP usually go along with hard starting or a hard start then dying. One other thing I found on 7.3l's was that there was a problem with the design of the sump pickup, that sometimes causes the pickup tube to crack. If you block the front wheels and jack up the rear end (or park it on an incline, nose down), and the pressure raises, then the pickup tube is most likely cracked. Raising it that way would raise the level at the sump above where it usually cracks. Checking and ruling that out might be a good idea... [/QUOTE]