NGC-GM V8 low-ish oil pressure, recommended additives?

[brider]

I searched "oil additives" but that's about it, didn't see anything that I could use.

Looking for an additive, or recommended oil/oil viscosity, to help the tired engine (193k miles) in my kid's '93 Range Rover 4.2L V8. It's a mid-90's fuel-injected version of an old Buick engine, aluminum block.

Always ran as well as it could, but now the oil light is beginning to flicker intermittently when you might expect; at idle, when it's hot. I taught the kid to rev it slightly when it happens to make it go out (I have no idea what the actual oil pressure it since there's no real guage). No knocking or clacking....yet.

I've test-driven this thing enough to know that IF the idiot light is somewhat accurately reporting the good/bad oil pressure, it is not in imminent danger of grenading, it's just showing it's wear on the mains.

Is there an additive that is worth using to try to artificially prop up the pressure, or add a little insurance to the mains? I really don't want to disappoint the younger kid who gets his license this fall and tell him dad needs to swap/rebuild the engine (which I'll never get around to doing).

Thanks!

[Don G]

Repair the reason for the low pressure or run heavier viscosity lube like 10-40 or 20-50 until it fails....   DonG

[bodine99]

Run straight valvoline VR-1 60wt

[Vagrant]

Repair the reason for the low pressure or run heavier viscosity lube like 10-40 or 20-50 until it fails....   DonG

that's what I'd do! it truly isn't many miles if it was cared for.

[brider]

Repairing the low-end isn't going to happen it time for the kid to drive it. I may have hinted at a rebuild but I already decided long ago that the next step is to drop a good 4.6 into it if comes to that.

Rather than search the 'net for recommendations, I figure I'd ask you guys. I KNOW that amongst this crowd somebody has tried something that gives results.

Straight 60? Seems kinda severe, but that's what I asked for, recommendations! Won't discount it!

[larrys]

Remember STP oil treatment? My high school shop teacher told us that if you used it and your motor ran better, then your motor was toast. Run straight 40 weight until it doesn't.
Be well,
Larry

[NoSprk]

are you sure the oil pressure sender is good? they are simple switches and can fail. id check that its not leaking. oil all over the sender can mess with the connection

[bigbikerrick]

A couple of cans of the old "STP" would be good ,if you could find some. I dont think they make that old thick as honey product these days. Remember the "racers edge" advertisements with Andy Granatelli?  I used to use that in my air cooled VWs back in the 70s,and it would help with oil pressure when the engine got a bit "loose". I remember they only held 3 quarts of oil, which would get real toasty when running at highway speeds in the  hot Arizona desert. I cant even imagine what the oil temps must have been  like in those 3 quarts , in a 69 bug hauling 4 full sized adults, and their luggage,coming in off the interstate headed into Tucson, in the summer.
  Yeah, I remember the STP helping keep the oil light from flickering at idle!
Rick.

[egschade]

are you sure the oil pressure sender is good? they are simple switches and can fail. id check that its not leaking. oil all over the sender can mess with the connection

+1 for that OR going to a garage who will put a proper oil pressure gauge on it. Putting extra heavy oil in an engine isn't a good idea IF the pressure is actually OK. Would also avoid straight weight heavy oil as it may be TOO thick when cold and you actually accelerate your engine wear because it doesn't get to the right places. Try a 20w-50 if that's what you think will work. Amazon sells it at $16 for a 5 quart jug of regular.

[Antietam Classic Cycle]

https://www.harborfreight.com/engine-oil-pressure-test-kit-62621.html

[brider]

https://www.harborfreight.com/engine-oil-pressure-test-kit-62621.html

Now THAT'S what I'm talkin' 'bout, although the suggestion of an oil pressure guage reminded me that THAT'S what i decided to do before I forgot and asked you guys about additives. I probably have 2-3 kits in the garage that I never installed thru the years on several old trucks I had.

Still, that link Charlie sent looks like one robust guage, but it might look kinda out-of-place in the refined old RR interior....

[Antietam Classic Cycle]

Now THAT'S what I'm talkin' 'bout, although the suggestion of an oil pressure guage reminded me that THAT'S what i decided to do before I forgot and asked you guys about additives. I probably have 2-3 kits in the garage that I never installed thru the years on several old trucks I had.

Still, that link Charlie sent looks like one robust guage, but it might look kinda out-of-place in the refined old RR interior....

It's not meant to be installed permanently, it's meant to be attached for the test and then removed. I have one and it works very well when used as intended.

[bmc5733946]

I have seen an occasion where the wiring to the oil sender was connected to the sender by a sealed plug. When the oil pressure sender started to leak it leaked into the sealed cavity, the seal doing what it was supposed to do kept the oil from leaving and allowed pressure to be applied to the back side of the switch diaphragm which turned the light on, still had great oil pressure. The wire could also be shorting out intermittently, best to check actual oil pressure as others have noted. Snake oil never works. (ducking for cover)

Brian

[moto-uno]

  The snake oils in their time used to raise the viscosity about 20 on the scale , a 10w became a 30w , but you wouldm't expect
it to last . A thicker multi-weight is a perfectly fine alternative . You don't live in the Yukon do you ? If it stays above 70 degrees
at nigh twhere you're at , then higher straight weights would be fine also . You are no longer dealing with a new tight clearanced
motor  .  Peter

[Tom H]

Years ago when I added a mechanical gauge to my '62 F100 262ci 6cyl, it scared me as to how low the pressure got even though the light never came on. Still is running with 40wt in it after all these years.

BTW. don't ever add a gauge to a hydro guzzi, at hot idle you'll swear that it's going to lock up due to lack of pressure.

Grab a gauge and see what it's at. 5-10#'s at hot idle and it should be good for quite some time. This is provided that it comes up to a reasonable number at speed.

Tom

[brider]

Years ago when I added a mechanical gauge to my '62 F100 262ci 6cyl, it scared me as to how low the pressure got even though the light never came on. Still is running with 40wt in it after all these years.

I had a '66 F250 with a 300 ci 6-cyl, and same story, guage read alarmingly low at warn idle. Came up nicely at running speed, though.

[larrys]

I made a test gauge from a known good Stewart Warner oil pressure gauge and a grease gun 12" flex hose. 1/8" NPT threads. Fits all the boat engines I've built.
Larry

[LowRyter]

These cars with OD transmissions can give you a little bit of a double take at speed.  My Duramax goes pretty low once it's warmed up.

[oldbike54]

 Gotta wonder what Click and Clack would say about this ?

 Dusty