6801

why are the stock oil gauges off so bad. my autometer shows 60psi 40 psi code brand new guage. i changed the oil and the needle spun past 100psi and wouldt work. i put the stock one back on and it shows about 15 warm and 40 cold. i put a used one back on and im back up to 60. is it better to run a line from above the oil filter instead of behind the intake?. also i used the stock sending unit and my abs light went out.

wrd1972

iTrader: (12)

This is my opinion. I have had 2 aftermarket sensors and one showed 25# at idle and the one I have now shows 20#. Both of these are NOT GM sensors, they cam from different parts houses. Its a variance in tollerances that are causing the differences. Also I think the PCM does not monitor the oil pressure so there is no computerized correction being provided to balance things out or self calibrate. If I am wrong, someone chime in.

If you want to make the dash guage more accurate to your mechanical unit, pull the needle of the dash guage and reinstall it to show the correct reading. Just be careful pushing it on.

jaycenk

iTrader: (1)

Mine is wrong too and I put the mechanical on there and then went back to the stocker and now I know what the stocker should say. I just ignor the fact that it tends to get stuck and jump and is also wrong. If it falls to 0 I know I better pull over and make sure it's the gage thats gone bad. Thats about all I use it for now.

fleetmgr

I think the best you can say about the stock gauge is that it will tell you that you have some oil pressure or you don't have any.

ADM

I put in a high pressure pump, changed the sensor to aftermarket.

I run 20w50 Castrol and get 60psi at cold idle, 20psi at hot idle, 40psi during normal cruising and up to 50psi at WOT (when car is warm).

Its freaking crazy!

SexyTransAm

iTrader: (6)

20w50? wow

wrd1972

iTrader: (12)

20W50 is not that unusual. But to have 20# at hot idle with it seems a bit low and indicates loose bearings.

JB_97ws6TA

iTrader: (6)

20 psi hot idle does not indicate loose bearings

wrd1972

iTrader: (12)

Notice I said with 20w50 oil.

I will restate that.
In my opinion, 20# at hot idle with 20W50 oil indicates bearings that are more on the looser side than the tighter side like one might find in a factory built LT1. 20w50 in a new LT1 would have some very high oil pressure. I know this because I once saw a guy do it and the hot idle was around 50-60. Put the 5w30 back in and it was around 25 or so.

When I say loose, I am am not saying its a problem.

ADM

I forgot to mention I was running the same hot idle psi when I was on the stock pump, and I was running 10w30. The cold idle was 40psi, and under hot WOT I would get 40psi. The needle always fluctuated back when I was using the stock sending unit and the stock pump when on hit idle.

It still did so with the new sending unit and GM high pressure pump. I have yet to run a mechanical gauge to confirm the accuracy of the gauge on the dashboard.