Oil pressure when hot? - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > TJ Jeep Wrangler Forum > TJ General Discussion Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 03-25-2012, 09:51 PM   #1
Jeeper
 
B-wils-TJ's Avatar
 
Join Date: Mar 2012
Posts: 97
Oil pressure when hot?

The oil pressure on my 4.0 tj is between 40-60 when first started, but drops to about 22 when it gets hot and is at idle.. I was wondering if this is normal because none of my other vehicles do this.

B-wils-TJ is offline   Quote Quick Reply
Old 03-25-2012, 10:37 PM   #2
Jeeper

WF Supporting Member
 
SippiTJ's Avatar
 
Join Date: Apr 2011
Posts: 266
Subscribed.

__________________
02 Apex
4 inch lift
Bilstein 5100 shocks
Smitty front and rear bumpers with tire carrier
Some other random little things.

I WANT TO GO TO MOAB!
SippiTJ is offline   Quote Quick Reply
Old 03-25-2012, 11:09 PM   #3
Jeeper
 
freeskier's Avatar
 
Join Date: Mar 2011
Location: Longmont, CO
Posts: 2,464
That is normal. On cold start the oil is thicker which creates more pressure. When it warms up the oil thins out and pressure drops.
freeskier is offline   Quote Quick Reply
Old 03-25-2012, 11:52 PM   #4
Jeeper
 
Join Date: Nov 2011
Location: Western Arkansas
Posts: 229
Totally normal for most vehicles. 22 psi oil pressure at hot idle will keep your engine alive. As my father-in-law said when I was concerned about my old Blazer oil pres dropping to 5 psi at idle; that's all a Chevy needs to run ain't it? It blew a few weeks after that....
Remus_Redbone is offline   Quote Quick Reply
Old 03-26-2012, 12:30 AM   #5
Jeeper
 
DevilDogDoc's Avatar
 
Join Date: Jun 2010
Location: Yucca Valley CA 20 miles from JV
Posts: 2,362
As long as it's over 13 at hot idle it's within spec per the FSM.
__________________
Violence may not be the answer but it sure cuts down on the stupid questions
DevilDogDoc is offline   Quote Quick Reply
Old 03-26-2012, 12:31 AM   #6
Jeeper
 
Sherpa's Avatar
 
Join Date: Oct 2010
Location: Lehi, UT
Posts: 1,049
Quote:
Originally Posted by B-wils-TJ View Post
The oil pressure on my 4.0 tj is between 40-60 when first started, but drops to about 22 when it gets hot and is at idle.. I was wondering if this is normal
It is normal. As someone else described, hot oil thins and will result in lower pressure than cold oil. Furthermore, oil pressure will rise and fall to an extent based on engine RPM.

Quote:
Originally Posted by B-wils-TJ View Post
because none of my other vehicles do this.
Actually, all of your other vehicles do this. Because consumers didn't understand the concept, they got nervous when an oil pressure gauge would drop in situations like you described. After many many complaints to dealership personnel, manufacturers began replacing actual oil pressure gauges with "dumb" gauges. A dumb gauge is really no more than a warning light; either the needle points to a "safe" reading or it flatlines to zero--there is no in between. Eventually, manufacturers realized the stupidity of installing these dumb gauges, so they were phased out entirely and replaced with warning lights.

Of course, this really pisses off those of us who (a) understand what is going on and (b) want actual functioning gauges in our vehicles.
__________________
Dempsey Bowling
My fleet: 91 Miata, 98 Wrangler Sport, 06 Mustang GT, 01 Suburban 8.1L, 14 Forte EX
Jeep mods: 4" longarm + 1" BL, 35" KM2s, 4.56s with dual ARBs... and lots of scratched armor
Sherpa is offline   Quote Quick Reply
Old 03-26-2012, 08:07 AM   #7
Jeeper
 
B-wils-TJ's Avatar
 
Join Date: Mar 2012
Posts: 97
Thanks for the info! Just wanted to check, I don't want to risk something like that on my baby!

B-wils-TJ is offline   Quote Quick Reply
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Engine running very hot! help please! Nicko YJ Tech Forum 36 04-15-2012 07:48 AM
Oil! Rear Breather Tube!! Help!!! dmitchell28 TJ General Discussion Forum 10 04-07-2012 04:43 PM
Can't diagnose fuel pressure problem dsmithwc04 YJ Tech Forum 6 03-26-2012 02:02 PM
Rule #1 when you have the top down..... mxman122 JK General Discussion Forum 33 03-25-2012 01:48 PM
Engine running way to hot! Please help! Nicko General Jeep Discussion 12 03-24-2012 10:27 PM


logo carid shop wrangler parts carid fender flares custom wheels store avs deflectors at carid
» Rates
Get low rates on auto insurance in Canada!

» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 02:58 AM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC