hey guys i got a ?. In the morning i start the jeep and the oil pressure guage reads like 60 and everything is fine and dandy. its when i have been driving it around for a while and the engine is warmed up and its warm outside that the guage will drop to around 40 or lower while idling. do u guys think its the oil pressure sending unit? if so i should just be able to do a quick swap of the "faulty" one right. (its right above the oil filter right?). thanks in advance.
Just let me get my hands on the guys that decided to install torx bolts on JEEPS!
That is perfectly normal. Cold oil has a higher viscosity resulting in a higher pressure at cold start up. Once its warmed up it will drop. 40 at idle is pretty good pressure. Around 20 at idle is normal for high milage +100k.
Less then 10 at idle and you need to have a good look at your main bearings
That is normal. Once the oil is warmed up the oil pressure should drop some at idle. As long as the pressure builds along with the RPMs you are fine. One of the local engine builders told me many years ago that as long as you have about 10 psi per 1000 RPM all is good. This is coming from a Ford guy that mainly builds race engines.
1990 Jeep YJ 4.2
Howell EFI, BDS 3.5" lift, M.O.R.E 5/8" Boomerang shackles, 1" Daystar BL, 1" JKS MML, TFI, Crager soft 8s w 35" Dunlop Mud Rovers, Ford 8.8, 4.88s, Dana 30 E-Locker, Terra Flex SYE, Tom Woods CV shaft, Warn M8000.
In 96 the Mustang changed from a "real" guage to a guage that is nothing more than an idiot light wih a needle. People wouild see the guage moving and think that there was a problem then head off to the dealer so then the dealer would have to convince the customer there was nothing wrong.