Mobil 1 and leaking ?? - Off-Road Forums & Discussion Groups
Jeep-Short Wheelbase All discussion of short wheelbase Jeeps: CJ, TJ, YJ and JK

LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 08-17-2004, 12:45 AM Thread Starter
webjeep's Avatar
Join Date: Mar 2002
Location: Richmond, VA
Posts: 921
Thanks: 0
Thanked 0 Times in 0 Posts
Mobil 1 and leaking ??

Ok, did the comlete teardown and rebuild w/exceptional machine work on the 360, got it all back together, installed and running like a champ. Did the break in with 10w 30 conventional and then drained and went to Mobil 1 10w30. Started leaking a bit from what appeared to be the rear main. I am about 2000 miles into the new engine and it is leaking like a seive from what still appears to be the rear main. I know that this is a problem with the synthetics, but i cannot afford to put this stuff in like its gas through my 4bbl. I have decided that i at least need to replace the rear main and i would like to continue running the mobil 1, but the question remains... will a new rear main fix the problem and if not, what do i need to do to fix it, this stuff is $$$. Any help or suggestions, this is the first time i have ever run synthetic in any of my engines.


webjeep is offline  
Sponsored Links
post #2 of (permalink) Old 08-17-2004, 02:17 AM
Keyboard Implanted
GeeAea's Avatar
Join Date: Sep 1999
Location: Pottstown, PA
Posts: 2,076
Thanks: 0
Thanked 1 Time in 1 Post
Re: Mobil 1 and leaking ??

Synth shouldn't have anything to do with that leak. A seal that new could care less what it sees. Well, perhaps aviation turbine oil would do a number on it.....

For more than you ever wanted to know about oil and it's effects on seals ..might I suggest BITOG
GeeAea is offline  
post #3 of (permalink) Old 08-17-2004, 04:09 PM
Join Date: Nov 2000
Posts: 2,687
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Mobil 1 and leaking ??

To state the obvious, there's something wrong with the seal or crank surface. Better replace the seal. It's possible the crank is worn from the old seal and won't seal up properly. Switching to another brand of seal sometimes helps if it rides in a slightly different spot on the crank. Be sure to oil the crank surface so it doesn't damage the seal on a dry start up.

If you do have a leaky seal, sythetic is worse, because it is less viscous at temperatures below operating temperature, and thus will leak more as it is thinner. It's the same viscosity at running temperature as a conventional oil.

Just compare how quickly it pours out of the container at room temperature compared to conventional oil of the same viscosity rating. I suspect this adds to the leak problems, as the oil is not at 190 degrees at all times, therefore not all things are equal.
TiminMb is offline  
Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the Off-Road Forums & Discussion Groups forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may not post new threads
You may not 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 On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome