my stock oil pressure gauge on my 1989 will only register at the second small mark on the gauge at 65 lbs.25 lbs.at the first small mark.there are seven small marks on the gauge and two longer ones at both ends.the indicator is slow to move.takes almost 40 seconds to go from 25lbs. at idle to 65 lbs. at 2000 rpms.same way going back down.i have a new sending unit at the block.i freshened up the gauge cluster as per jim lanes write up.even soldered a ground on the board behind gauge cluster.i also tried another gauge (used),same thing.i would really like to use only the factory gauges and not put an aftermarket gauge in the truck.i would really like the needle to move more if that is possible.any ideas? i'm ready to give up.by the way,my 90 doesn't act like this.the needle goes to almost 1/2 gauge when running down the road.

 

Well sounds like your gauge is working properly then....

The factory Oil pressure gauges pretty much all act the same. The fact your 90 moves quickly and registers more accurately I think is an anomaly.

You could send your factory gauges down to Redline Gauges and have them fit the stock gauge cluster with a mechanical oil pressure gauge.

 

Get a mechanical gauge. I'm running one, and my factory gauge works great. I just don't mess around with oil pressure in a vehicle that has a motor worth more than the truck