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Oil pressure too high? Pics inside!

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Old Feb 9, 2012 | 04:40 PM
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Default Oil pressure too high? Pics inside!

Is my oil pressure too high? Or have I just never payed enough attention to the oil pressure gauge? I assume it should be more towards the middle of the gauge at only ~2200 rpm..

The first pic is at 2200 rpm. The second one is idling at 750 rpm.

Lemme know what you guys think!



Oil pressure too high? Pics inside!-image-4118343360.jpg



Oil pressure too high? Pics inside!-image-2750598591.jpg
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Old Feb 9, 2012 | 04:43 PM
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haha mine is always close to 80 but I think my guage is busted? it never fluctuates only when i turn my xj off does it go to 0? i dunno.
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Old Feb 9, 2012 | 04:46 PM
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is that fully warmed up? or within the first 20 min +/- of start up?

spec is no less than 13psi at HOT idle
37-75psi above 1600rpm

hot idle is considered with the engine fully warmed up (oil takes much longer to reach operating temp than coolant)
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Old Feb 9, 2012 | 05:28 PM
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I had been driving about 20 minutes.. So that would be normal pressure?

I was changing my oil the other night (after downing a few drinks) and forgot to change the filter. I figured the filter only held .5 quarts so I just added 5.5 quarts and decided I would do an early oil change next time since I missed the filter. I'm hoping I didnt over fill it and cause any issues haha.
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Old Feb 9, 2012 | 05:31 PM
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Originally Posted by The91XJ
I had been driving about 20 minutes.. So that would be normal pressure?

I was changing my oil the other night (after downing a few drinks) and forgot to change the filter. I figured the filter only held .5 quarts so I just added 5.5 quarts and decided I would do an early oil change next time since I missed the filter. I'm hoping I didnt over fill it and cause any issues haha.
well it's easy enough to check if you did or not lol

and you can change the filter without draining the oil - i would highly recommend doing so, the oil lasts much longer than a filter will. Some people change the filter every 5000 miles, but run the oil to 10000+ (verified ok by used oil anaylsis)

watch it on a longer trip and see if it goes back down to normal. What weight oil are you using?
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Old Feb 9, 2012 | 05:59 PM
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I've always used the basic castrol 10w30. I never let the jeep roll one mile past 3k between oil changes. I'm weird about maintenance ha.
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Old Feb 9, 2012 | 06:13 PM
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I think your oil pressure sending unit is failing. It is a VERY common failure on the 4.0 engine. When the fail, they fail with "higher" readings more often than lower readings, although it can go both ways.

I recommend purchasing these directly from Jeep. Well worth the extra $20 for the best reliability/accuracy/mating with your factory gauge.
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Old Feb 9, 2012 | 07:07 PM
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Originally Posted by tjwalker
I think your oil pressure sending unit is failing. It is a VERY common failure on the 4.0 engine. When the fail, they fail with "higher" readings more often than lower readings, although it can go both ways.

I recommend purchasing these directly from Jeep. Well worth the extra $20 for the best reliability/accuracy/mating with your factory gauge.
Yep, I had to replace mine last year. You could put 10 gallons of oil in it and it still wouldn't raise the pressure.
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Old Feb 9, 2012 | 10:49 PM
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Thanks for the advice guys! I'll look into that sending unit!
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Old Feb 10, 2012 | 09:38 AM
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Originally Posted by dukie564
well it's easy enough to check if you did or not lol

and you can change the filter without draining the oil - i would highly recommend doing so, the oil lasts much longer than a filter will. Some people change the filter every 5000 miles, but run the oil to 10000+ (verified ok by used oil anaylsis)

watch it on a longer trip and see if it goes back down to normal. What weight oil are you using?
I didn't know that.....thx!
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Old Feb 10, 2012 | 10:09 AM
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how much oil do you add when you swap out the filter, about a quart? or do you just check the level
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Old Feb 10, 2012 | 10:11 AM
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maybe 1/2 quart - prime the filter and install, run a few minutes, shut off, then check the level after it settles
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Old Feb 12, 2012 | 06:56 PM
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Mine is about 20 on hot idle and then goes to 50 when around 2000+rpm
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