Weird oil pressure, time for a guage, or high volume pump?

[uglytruk]

My recently aquired '87 Sub 6.2 runs really well, doesn't smoke at all, and is quiet cold or hot. So why when I'm riding around does the oil pressure appear to drop? I noticed it as low as 5 lbs, and the needle seems to respond to RPM, so I sorta trust it. I thought the oil pickup might be blocked with sludge, so occasionaly I'll turn the engine off for a few seconds, then re-start. All while going down the road at 60 mph. I filled with Rotella syn 10W40, AC Delco filter. Oil was clean after 1000 miles, a sign of frequent maintenance. Odo shows 70k, mabe 170k. Temperature is below freezing, runs 200f. I will change sender, and might install a quality mech guage.

So my question is, does somebody make a HIGH VOLUME oil pump? Melling lists only the standard unit. I would also install the steel shaft.

 

[pauly383]

I can't say anything about the diesel pumps , as I just don't know .

What I can talk about is the damn factory gauges . Replacing the sender may not fix it , as it does already move with rpm . Try another gauge . In my case the gauge was bad and always read low , and never went more than maybe the first notch .

Mine always read low , until I scored some more gauges to try out . I liked the look of mine , so I swapped the ceramic resistor off the back of the newer one that was know to work , onto the old one . My oil pressure read right after that . I have over half at idle warm now , and over 3/4 when driving , and can peg it when the temps and viscosity is at teh right spot .

Now I have swapped the whole gauge . Found a newer one that read to 80 psi ( my 83 stock one was to 60 psi ) .

 

[colbystephens]

what's normal cruising speed oil pressure in the 6.2?

 

[pauly383]

Have no idea about that . I just knwo about the gauges in the k trucks .

Try these threads :
http://www.coloradok5.com/forums/archive/index.php/t-18007.html
http://www.coloradok5.com/forums/archive/index.php/t-24800.html

 

[uglytruk]

I'm going to put a tee in the sender, and also change to the sender from my "dead" Banks 6.2. It was reliable. And the old Stewart Warner mechanical is the way to go. Maybe I'll use a 3/16th (instead of 1/8th) line to get a more accurate reading...

 

[uglytruk]

My '83 gas 305 definitly has more oil pressure than what little I've seen of the Diesels. You'd think it would be the oppossite as the diesels run such high compression. Lots of pressure to keep off the the rod bearings...