Long story short, I didn't torque down my oil drain plug and lost all my oil. It's fine. I caught it before anything bit the dust.

But my gauge is confusing me. Instead of showing low oil pressure, it jumped around like it had a bad connection. I thought it was going to break the needle off. As it leaked oil, it went from a occasional jump to constant thrashing. But it always returned right to the middle instantly. It took the truck starting to tap for me to recognize the oil was low (I just changed it last week, so I was positive it was a bad connection, not low oil . . . until it tapped).

Shouldn't it get low if I have low or intermittent oil pressure? It doesn't really even move much if I almost stall it or stall it. WTH?

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2003 Ranger XLT Extended Cab, 4x2, 3.0, M5OD, 3.73 open

1989 Dodge D250, 4x2, 318, TF727, 3.91 open

*GONE* 1993 Ranger XL 2.3, M5OD, 114k, bent, mangled, dented, wrecked, smashed, and still ran good

My truck usually keeps oil pressure so idk lol

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95 Ranger XLT 4x2 2.3 I4 5 speed 206,000 *dead*
96 Ranger XLT 4x4 4.0 V6 5 speed 173,000 *alive*
D35 front, 8.8 rear, 3.73 gears, limited slip rear diff

The oil gauge is really just an idiot light. If you have pressure over 7 psi, or so, it reads normal. Otherwise, it reads low. It doesn't really read the amount of pressure...just whether there is pressure or not.

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2000 Ford Ranger XLT
Extended Cab
3.0 Flex
4x4
Manual Transmission
Offroad Package

The reason it was jumping around like that was because your oil was low enough that the pump was sucking air. No oil leads to the tapping noise you heard, you're lucky you caught it in time.

I heard that about it basically being an idiot light with a needle. Is there any way to convert it to an actual graduated gauge?

I'd like to know about it if my oil pressure is 9psi too, you know what I mean? Yeah, its good that it will let you know before its absolutely zero, but 8-10 is bad enough!

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2003 Ranger XLT Extended Cab, 4x2, 3.0, M5OD, 3.73 open

1989 Dodge D250, 4x2, 318, TF727, 3.91 open

*GONE* 1993 Ranger XL 2.3, M5OD, 114k, bent, mangled, dented, wrecked, smashed, and still ran good

I believe you can tee off the sending unit switch and run a mechanical gauge in the cab. I did it on a ford contour I had, same with the coolant temp. I was too cheap to buy a new gauge cluster so I ended up spending the same amount or more putting actual gauges in it. if you want correct readings use quality mechanical gauges, ie autometer. sunpro gauges are what I used and never had issues, then again it wasn't a all out race car, just a commuter. I plan on doing the same to my ranger, just cause I prefer gauges over idiot lights.

also if your engine has a min of 4psi of oil pressure your ok, my c15 cat in a freightliner has 11psi at idle and 62psi at 1500rpm. so if a 3.0l gas engine has atleast 4psi its alright. my cat is pushing 475hp with 1350ftlbs of tq. and It burns 5.23mpg.

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2001 Ranger XLT 3.0L v6 stock trans 3.73 264,000 and counting on original eng/trans/rear. MODS so far: Specter Washable airfilter, Throttle cable mod.
Coming soon: 4 wheel disc brakes, expo gauges, new 3.0 with new exaust.

Did some research today. The threads on the oil pressure switch are a 1/4-18npt. Basically a 1/4pipe thread. Any hardware store, lowes or home depot, should carry a tee in that size, most ice makers in freezers use a similar size. If they dont have it check with a plumbers supply.

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2001 Ranger XLT 3.0L v6 stock trans 3.73 264,000 and counting on original eng/trans/rear. MODS so far: Specter Washable airfilter, Throttle cable mod.
Coming soon: 4 wheel disc brakes, expo gauges, new 3.0 with new exaust.