I notice my oil pressure drops to about 25psi at idle a week ago, it was time to change the oil so I dident think much of it. I changed the oil today and its still at 25psi at idle. Befor it would hold stedy at 40psi now it dosent. what changed.

The oil that came out looked ok about 3500 miles from the last change. I use Delo 15-40 and Fleetguard filters and changed the oil about every 3000 miles.

 

put a manual guage on it ..... i think you have a 1/8th pipe plug on top of your oil filter housing to test pressure. you might be surprised

 

Thanks, I'll try that. any body else?

 

The factory gauge will show 40psi at idle after a long hot run (hill, load, etc); my real gauge shows ~10-12 psi at idle.

THe factory gauge is heavily damped and driven by the computer!

Install a real gauge & quit guessing!

HTH

Tony

 

the input is great. Though what Im wondering is what changed? Is the gauge just doing its factory (wired) thing. Im not too conserned, but the change is makes me think a little and was wondering your thoughts. thanks

 

I tend to agree it is the change that is worrying. I have the factory gauge it starts out at around 45 when cold then drops to around 38 when warm at idle. goes back to 40 under load.

 

The change that Im talking about is that 2 weeks ago it stayed stedy at 40psi all the time. within 5 day it decresed to 25 psi at idle when warmed up, 40 psi running and 40psi cold. So in a week when warm it decresed 15 psi.

 

You are using the gauge exactly as gauges are designed and it warning of you of something due to the change. I still concur, confirm with a manual gauge - most typical problem is the sender is going bad, but they aren't too cheap.

 

I was afraid of the sending unit. I'll check it with a manual gauge. Thanks guys.