At idle, when warmed up, the pressure looks to be around the first line iirc. This puts it at about 18-22 (I'll have to look again to see if it's slightly over or under, can't remember right now). What's normal for these, during normal driving it goes up past the middle line for sure, just making sure the idle is sufficient(granted the gauge is accurate)
Normal oil pressure on 4.0?
markzeronine
21 - 40 of 57 Posts
Joined
·
185 Posts
I'd have to guess 2000 was the last year with a "real" gauge. I have a late 2000 build year.
But yeah looks like I'm normal. Thanks guys
But yeah looks like I'm normal. Thanks guys
my BMW has a "dummy" gauge and its oddly comforting
but i dont think its as bad as you guys describe - i tap in to the computer and i can see the true collant temperature and it will start to move if the car gets too hot. I do like that under normal conditions it never moves - and the few times i see it move i know there is something wrong, so it can work both ways, and it gives plenty of time.
but i dont think its as bad as you guys describe - i tap in to the computer and i can see the true collant temperature and it will start to move if the car gets too hot. I do like that under normal conditions it never moves - and the few times i see it move i know there is something wrong, so it can work both ways, and it gives plenty of time.
Joined
·
1 Posts
along the same lines - on oil pressure
I've got a '97 wrangler - 4 cycl - and for the most part the oil pressure reads about 42. Twice in the last month, both times the car was idling at a long light, the pressure started to fluctuate, and then dropped with the warning light/buzzer going off. I tapped the gas and the pressure kicked back up. Now a lights I keep an eye on the pressure and if it starts to drop, tap the gas. When the car is actually moving, the pressure is steady at 42.
The mechanics reply was $500 to replace the oil pump, which he claims commonly goes on Jeeps. Any thoughts? Real problem, something going, or basically normal.
If there were just idiot lights, I wouldn't have notice anything, except for the two quick lights/buzzer.
thanks in advance,
joe
I've got a '97 wrangler - 4 cycl - and for the most part the oil pressure reads about 42. Twice in the last month, both times the car was idling at a long light, the pressure started to fluctuate, and then dropped with the warning light/buzzer going off. I tapped the gas and the pressure kicked back up. Now a lights I keep an eye on the pressure and if it starts to drop, tap the gas. When the car is actually moving, the pressure is steady at 42.
The mechanics reply was $500 to replace the oil pump, which he claims commonly goes on Jeeps. Any thoughts? Real problem, something going, or basically normal.
If there were just idiot lights, I wouldn't have notice anything, except for the two quick lights/buzzer.
thanks in advance,
joe
Joined
·
420 Posts
My 2005 sits in the middle, but climbs while under load so it cant be a total dummy guage.
Mine is 2005 and does the same. This should be normal ??
Joined
·
437 Posts
Same with me
Yes it is normal. Mine sits halfway and then when I get moving it climbs just a tad and sits there while driving.
I noticed with my 91 YJ with the 2.5 I noticed low oil pressure it meant it was low on oil.
Normal pressure has gone way up!
My 2002 Wrangler 4.0 with 172,000 miles normally runs at about 40-50 PSI at 50-55 MPH. In the past couple of weeks it has begun showing progressively higher pressure to about 78 PSI at 50-plus MPH, always stopping just shy of 80 PSI. Only 2,500 miles on oil and filter change. Oil level is at full line. Am I causing damage at 80 PSI? Why would the pressure just start increasing? Should I try replacing the oil filter or replace the guage? Is there any way to electrically check the guage? Thanks, guys!
My 2002 Wrangler 4.0 with 172,000 miles normally runs at about 40-50 PSI at 50-55 MPH. In the past couple of weeks it has begun showing progressively higher pressure to about 78 PSI at 50-plus MPH, always stopping just shy of 80 PSI. Only 2,500 miles on oil and filter change. Oil level is at full line. Am I causing damage at 80 PSI? Why would the pressure just start increasing? Should I try replacing the oil filter or replace the guage? Is there any way to electrically check the guage? Thanks, guys!
2004 Wrangler TJ, 42RLE auto trans. F/R lockers, 5.38 gears, Warn Winch, Currie 4" Suspension
Joined
·
51,867 Posts
Most likely just a bad oil pressure sender, replace it with a Mopar replacement. Aftermarket oil pressure senders have a bad reputation, especially store brands. This is a very common problem with TJs.
Joined
·
1,193 Posts
Jerry, how bout the inverse? After warm n driving awhile (00, 4.0 auto, 137k, ) and at idle, always at 20 psi...exactly on that mark. Now a few months after chging oil sensor, now idles at 1 full tick mark Below 20.
Btw, used MOPAR sensor
Joined
·
398 Posts
Mine always runs extremely low. Below the 20 mark except for on cold mornings at start up it'll be in the middle. If i come close to killing it it'll drop down to nothing and the check gauge light will come on and go away when I put some load to the engine.
2004 Wrangler TJ, 42RLE auto trans. F/R lockers, 5.38 gears, Warn Winch, Currie 4" Suspension
Joined
·
51,867 Posts
Acceptable oil pressure is 10 psi per thousand engine rpms. The oil pump is engine driven so the real oil pressure rises and falls in step with the engine rpms. Early TJ oil pressure gauges show the true oil pressure complete with its ups and downs. Later TJs around 2003 had their oil pressure gauges reprogrammed to stay mid-scale no matter what the real oil pressure is. The factory changed it because most new TJ buyers had never had a real oil pressure gauge before and too many refused to believe the oil pressure was supposed to vary up and down. Dealers were getting buried in complaints about the oil pressure dropping at low or idle engine rpms, they asked the factory to reprogram it for that reason.
Joined
·
96 Posts
..Sounds like Jeep adopted Ford's idiot oil gauge (idiot light shaped like a gauge) philosophy to con/mislead less than knowledgeable consumers...
Does anyone know if some functionality can be returned to the gauge by installing a pressure sensor as on some older Fords? ... or is the "gauge" entirely computer driven?
Enjoy!
Does anyone know if some functionality can be returned to the gauge by installing a pressure sensor as on some older Fords? ... or is the "gauge" entirely computer driven?
Enjoy!
2004 Wrangler TJ, 42RLE auto trans. F/R lockers, 5.38 gears, Warn Winch, Currie 4" Suspension
Joined
·
51,867 Posts
All TJ gauges are 100% computer driven.
Joined
·
1,193 Posts
So Jerry, given that mine is an 00, is my drop in oil press real? Never dropped below 20 on the mark till month or so ago. Cause(s)?
2004 Wrangler TJ, 42RLE auto trans. F/R lockers, 5.38 gears, Warn Winch, Currie 4" Suspension
Joined
·
51,867 Posts
Yes your oil pressure variations are, as described above, 'real' and normal. Just keep in mind the rule-of-thumb of 10 psi of oil pressure per thousand engine rpms being acceptable to know if it's ok or not. And perhaps you just never noticed it dropping at idle rpms.
Joined
·
13,786 Posts
When in doubt get a good mechanical oil pressure gauge and use that for the readings. That takes all guess work out of the equation. It will help to verify if there is a problem with the dash gauge, sending unit, the oil pump and/or bearings.
Joined
·
96 Posts
Thanx!
I was afraid of that...
looks like its time for an A pillar gauge pod
https://www.quadratec.com/products/12500_211.htm
along with an electric oil pressure gauge and electric transmission temp gauge...(had too many broken oil lines (messy) and blown mechanical gauges to use them, personal choice).
I have heard that there are OPD (Oil Pump drive) problems on some 2005 and 2006 TJs; so I will likely order & install a Crown replacement OPD as preventative maintenance.
Still reducing the poor OEM design issues in this (new to me) TJ.
Enjoy!
All 05 and 06 4.0s have the defective OPDA. You need to pull it and check for gear wear and the shaft binding. Easy to do, and there are plenty of videos on how to do it out there. Failure can occur at any mileage. If it seizes and the gear fractures, you will have 0 PSI oil pressure and engine failure if you don't shut it down immediately.
21 - 40 of 57 Posts
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
-
?
