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: Wacky oil pressure guage


Diesel Dragon
01-12-2005, 12:34 PM
I have been having trouble with my oil pressure guage reading low or "0" :eek:
Started about 3 month's ago. When truck was not yet fully warmed up but not cold either usually temp guage would be at 180 deg but I don't think the thermostat opened yet, when I would come to a stop and idle the guage would read 0 and the DIC would say low oil pressure, and if I reved it up the pressure would only go up to 30 psi instead of 60. The guage would not be steady and would go wacky from 0 to 30 to 60.-:t
I brought it to the dealer who had it for a couple of days and of course they "could not duplicate" it so what he did was change the oil pressure sending unit for me. I thought that was a good possibility for the problem too.
All was well for a couple of months and then it started again. so back to the dealer I go and he tries another sending unit again saying something about a new part # and maybe it was redesigned.
Well this time it only lasted a few days and started again.

It only does it intermintentlly, some times I could go a week with no problem's and sometimes it would do it a few days in a row, but it's always been only when the truck is just getting up to normal operating temp but hasen't gotten fully hot yet. Once the temp goes up to 200 or so it won't do it again for the rest of the day even if it cools back down to 180.

Oil level is good and I don't hear any mechanical knock like it was actually starving for oil, so I think it's a electrical problem and not a mechanical one but who know's. Truck is sitting on level ground, and it will read bad whether it's idling (0 psi ) or running at 2000 rpm's (30 psi).

I had problem's with the guage cluster last year when it would not come on when truck was started but after I found the batt cables loose at the starter and tightened them up I have not had a problem with the cluster since.:)

And this time it's only the oil pressure guage that's acting weird the other's are fine.

So to recap:
1. Temp is about 180 but not warmed up yet.
2. Once it fully warm's up it works normal again.
3. Oil sending unit's have been changed twice already.
4. Only does it intermintally, some times I can go a whole week with no problem's, and other times it's every day for a week.

So does any one have any idea's or had a similar problem with their's and had it repaired.

Any Tech's heard of anything like this before?

I'm baffled :confused: and I don't like that little chime on the DIC "ding ding ding" oil pressure low.


Thx for any help
Diesel Dragon

aprr454
01-12-2005, 05:05 PM
Might be the gauge itself, in the cluster. I just got a new cluster last night and the oil pressure gauge is screw up. 120psi at an idle.

TazMan
01-12-2005, 09:24 PM
I got a new cluster because of speedo pegged at 140. The cluster came off an older truck. The oil press is 120 until it warms up to 180+. I have not gone back in... yet.

Diesel Dragon
01-13-2005, 11:09 AM
Aprr454 and Tazman,

Are your guages screwed up all the time, when the engine is cold and hot, or only at certain times like mine?

problemchild
01-13-2005, 11:33 AM
My whole cluster had to be replaced because the guages were "sticking" or reading eratic.

But my oil pressure guage is low all the time 55 cruise 14 idle

Diesel Dragon
01-13-2005, 11:41 AM
You have the worst luck PC

Try changing the Oil pressure sending unit. When the dealer changed mine last time the pressure went from 60 at cruise to 65. Idle is still the same at 25

aprr454
01-13-2005, 04:58 PM
My oil pressure gauge reads 35-40 at idle when engine is fully warmed up. 85-90 at 55mph. Start it when its cold, 120 at idle.