Rear Main Seal Bearing Cap. - Jeep Cherokee Forum

Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here XJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.

Rear Main Seal Bearing Cap.

Reply

 
 
 
Old 11-01-2011, 09:51 PM
  #1  
CF Veteran
Thread Starter
 
aquickmopar's Avatar
 
Join Date: Jan 2011
Location: Virginia
Posts: 1,635
Year: 1999
Model: Cherokee
Engine: 4.0
Default Rear Main Seal Bearing Cap.

Im in the middle of replacing my rear main seal and oil pan gasket on my 96 4.0 cherokee. When I dropped the oil pan there was some sort of long bracket plate thet connected each bearing cap together I had to romove that to be able to romove the rear main bearing cap to change the rear main seal. I believe once I change the rear main seal the rear main bearing cap bolts get torqued to 80lbs. But what torque spec is the long plate I had to take off for all those? And what torque spec for the oil pan as well?
aquickmopar is offline  
Reply With Quote
Old 11-02-2011, 01:57 AM
  #2  
kjc
CF Veteran
 
kjc's Avatar
 
Join Date: Aug 2011
Location: Blue Springs, MO
Posts: 1,012
Year: 1993
Model: Grand Cherokee
Engine: 4.0L Laredo
Default Main bearing / oil pan bolts torq

Here's what I could find in the FSM

As far as the sort of long bracket plate that connected each bearing cap together.. I couldn't find anything on it. I'd just make them good and snug.. inch/lbs not ft/lbs Hope this helps some
Attached Images  
kjc is offline  
Reply With Quote
Old 11-02-2011, 04:19 PM
  #3  
CF Veteran
 
s14unimog's Avatar
 
Join Date: Dec 2009
Posts: 1,396
Model: Cherokee
Default

Originally Posted by aquickmopar View Post
When I dropped the oil pan there was some sort of long bracket plate thet connected each bearing cap together.
= Crank Girdle

I don't remember if I hit 80ft/lbs on them or not when I did mine. I think I just snugged it down good. It's bracing everything together, so it's not as important as the caps are.
s14unimog is offline  
Reply With Quote
Old 11-22-2011, 12:55 AM
  #4  
Senior Member
 
jeep19xj91's Avatar
 
Join Date: Jul 2011
Location: Red Lion, PA
Posts: 675
Year: 1991
Model: Cherokee(XJ)
Engine: 4.0
Default

Thats called a main girdle, it basically strengthens the whole bottom end. It probably gets torqued to the same as the mains but dont take my word for it.
jeep19xj91 is offline  
Reply With Quote
Old 11-22-2011, 08:16 PM
  #5  
CF Veteran
 
5-90's Avatar
 
Join Date: May 2008
Posts: 3,018
Year: 1988
Model: Cherokee
Engine: AMC242
Default

Originally Posted by aquickmopar View Post
Im in the middle of replacing my rear main seal and oil pan gasket on my 96 4.0 cherokee. When I dropped the oil pan there was some sort of long bracket plate thet connected each bearing cap together I had to romove that to be able to romove the rear main bearing cap to change the rear main seal. I believe once I change the rear main seal the rear main bearing cap bolts get torqued to 80lbs. But what torque spec is the long plate I had to take off for all those? And what torque spec for the oil pan as well?
That bracket that you're referring to is the "main bearing cap brace" - it was added in 1996 (I'm not sure why, since the AMC is a seven-main I6 block it's plenty stiff...) but there you go.

Torque the main bearing cap screws to 80 pound-feet, torque the retaining nuts for the brace to 35-40 pound-feet. Apply assembly lube to any bearing you remove or loosen - and be generous with the stuff (cheap insurance.)

The oil sump screws have two torque values - the 1/4"-20 screws (7/16" socket) torque to 84 pound-inches/7 pound-feet, and the 5/16"-18 screws (1/2" wrench) get 132 pound-inches/11 pound-feet. DO NOT OVERTIGHTEN THESE SCREWS!.

Using the later one-piece moulded oil sump gasket means you don't have to worry about fighting to get four pieces lined up right, and don't have to get the corners sealed. Just make sure that you get the end rails in the proper place, but that should be fairly obvious. Do not tighten any of the oil sump screws until you have all of them in place and the threads engaged! Trust me on this one... No sealer should be necessary for the gasket proper, just make sure the mating surfaces are clean.

That should do it for the advice on this job - let us know if you run into anything else.
5-90 is offline  
Reply With Quote
Old 11-07-2015, 11:47 PM
  #6  
Newbie
 
Join Date: Oct 2015
Posts: 3
Year: 1999
Model: Cherokee
Engine: 4.0L
Default Main Bearing Cap Bolts, Main Bearing Cap Brace/Girdle Torque

The Jeep 4.0L main bearing cap bolts are custom bolts found only at a Jeep dealership. All 14 of these bolts have a 1/2" diameter partially threaded (1/2 - 13) hex bolt that hold the bearing caps to the engine block. The other end of the bolts, have a 3/8" diameter threaded (3/8 - 16) stud that holds the bearing cap brace/girdle to the seven bearing caps.

You will need a 13/16" deep socket for the custom hex bolts and a 9/16" socket for the nuts that hold the bearing cap brace to the bearing caps.

The 13/16" hex portion of the bolt is torqued to 80 ft/lbs and the 9/16" nut holding the bearing cap brace to the bearing cap should only be torqued to 35 ft/lbs.

If you over torque either portion of the bolt, Replace the Bolt!
You can only find these custom bolts from your Jeep Chrysler dealership from the Parts department. As of November 2015 in my region, a new main cap bolt runs around $6 and a new nut for $1.

Beyond my better judgement, I used a cheap torque wrench that did not pop at 35 ft/lbs after moving from 80 ft/lbs and the nut received probably about 60 ft/lbs before realizing that something was definitely wrong with the wrench. Needless to say, at approx. 60 ft/lbs the 3/8” threaded stud thinned/twisted/stretched where the nut was over torqued so I can imagine it probably wouldn’t take much more force before twisting/breaking the 3/8" threaded stud right off the bolt.

1996 and newer engine models have a main bearing cap brace/girdle, so if you have a brace and are considering an upgrade to ARP hex bolts or studs instead of factory replacement bolts, the bearing cap brace will not work as it can only fit over a 3/8" stud; ARP bolts and studs are a solid 1/2" diameter end to end and possibly too short for the additional thickness of the brace. As of this writing, ARP did not make a two size bolt or stud for the Jeep 4.0L to compensate for a bearing cap brace if you have one. FYI
I preferred the extra structural support the brace provides to the main bearing caps so I went with one factory replacement bolt and nut which was also much less expensive and time consuming… $7 in my case.

So my two cents to those replacing the rear main crank seal for the first time:
Do Not Use a Cheap Torque Wrench! They may not be reliable.
Don't go over 80 ft/lbs and don't go over 35 ft/lbs and Do Replace the Bolt from your Jeep dealership if either gets over torqued!

I hope this can be as useful to someone out there like the Cherokee forum posts have help me avoid some of the pitfalls in Jeep maintenance.

Last edited by 99 Jeep Cherokee 4.0L; 11-08-2015 at 07:41 PM. Reason: typos
99 Jeep Cherokee 4.0L is offline  
Reply With Quote
 
 
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
t.mcginley.jr
Jeep Builds
90
03-03-2018 10:06 PM
MOPAR87
Accessories
3
01-02-2016 06:52 PM
shelby5041
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
39
11-07-2015 02:22 AM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

Thread Tools
Search this Thread
Quick Reply: Rear Main Seal Bearing Cap.


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description: