Wheel Bearings turns into my axle rebuild thread - Page 2 - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Grand Cherokee & Commander Forums > ZJ Grand Cherokee Forum > Wheel Bearings turns into my axle rebuild thread

The RuffStuff "I can't go to EJS" Sale!Offset Tie Rod Kit From RuffStuff!Check out our NEW Steering Stuff!

Reply
Unread 07-23-2013, 12:23 PM   #16
zjosh93
Registered User
1993 ZJ 
 
Join Date: Aug 2010
Location: Austin
Posts: 994
Are you sure about the shop only taking off 1/2 thousandth from the cap? The caps look like investment castings and it looks like they took enough off the take the crown off the casting. I also don't see how cutting 1/2 thousandth from the cap is going to repair ten thousandths of wear into the housing and cap (5 thousandths on each side). I was looking as the angled section near the end of the cap and it looks visibly shorter than the uncut cap. I'd think you'd need to cut at least 10 thousandths which is about how much that looks like.

Also, why didn't Jeep cut the ends of the caps in the first place? That seems like a problem waiting to happen. If the mating surfaces aren't flat and similarly shaped they will wear into each other over time and you will lose your bearing crush especially with aluminum.

zjosh93 is offline   Reply With Quote
Unread 07-23-2013, 01:35 PM   #17
stageninja
That Rigger Guy
 
stageninja's Avatar
1997 ZJ 
 
Join Date: Apr 2007
Location: Indianapolis, IN
Posts: 566
Quote:
Originally Posted by zjosh93 View Post
Are you sure about the shop only taking off 1/2 thousandth from the cap? The caps look like investment castings and it looks like they took enough off the take the crown off the casting. I also don't see how cutting 1/2 thousandth from the cap is going to repair ten thousandths of wear into the housing and cap (5 thousandths on each side). I was looking as the angled section near the end of the cap and it looks visibly shorter than the uncut cap. I'd think you'd need to cut at least 10 thousandths which is about how much that looks like.

Also, why didn't Jeep cut the ends of the caps in the first place? That seems like a problem waiting to happen. If the mating surfaces aren't flat and similarly shaped they will wear into each other over time and you will lose your bearing crush especially with aluminum.
After measuring both caps, Inside the top of the 1/2 circle and the height of both caps, none of the measurements were the same even within the same cap. I have good contact now and with proper torque everything is tight. I can see why the "reputable shop" had to persuade the shim into place. I used a brass rod ie; if your going to beat something into place use a softer material between the beater and the beatee.
brass_rod.jpg

My next post is the gear patterns.
__________________
Mine '97 White, ZJ Ltd, 5.2, Up-Country Suspension, Kolak ignition, Kolak/Magnaflow Exhaust
Her's '98 Chargold ZJ Ltd. 4.0 2wd
Our 1st '97 White, ZJ Ltd, 5.2, The parts Jeep for 5 years...R.I.P. Sent to Pic-A-Part 5/17/2013

stageninja is offline   Reply With Quote
Unread 07-23-2013, 01:39 PM   #18
stageninja
That Rigger Guy
 
stageninja's Avatar
1997 ZJ 
 
Join Date: Apr 2007
Location: Indianapolis, IN
Posts: 566
Now that I have checked gear patterns I think that "reputable shop" reversed the factory shims.
The 1st 2 photos with yellow paint are with shims oriented as they came apart during tear down.

The 2 with blue/green paint are after I reversed them.
gear_pat_1.jpg

gear_pat_1a.jpg

gear_pat_2.jpg

gear_pat_2a.jpg

What do you all think?
__________________
Mine '97 White, ZJ Ltd, 5.2, Up-Country Suspension, Kolak ignition, Kolak/Magnaflow Exhaust
Her's '98 Chargold ZJ Ltd. 4.0 2wd
Our 1st '97 White, ZJ Ltd, 5.2, The parts Jeep for 5 years...R.I.P. Sent to Pic-A-Part 5/17/2013

stageninja is offline   Reply With Quote
Unread 07-23-2013, 01:45 PM   #19
zjosh93
Registered User
1993 ZJ 
 
Join Date: Aug 2010
Location: Austin
Posts: 994
What is your backlash either way? They make a case spreader for the Dana rear end but I never hear about people using it. I suppose using a brass drift works just as well.
zjosh93 is offline   Reply With Quote
Unread 07-23-2013, 02:09 PM   #20
stageninja
That Rigger Guy
 
stageninja's Avatar
1997 ZJ 
 
Join Date: Apr 2007
Location: Indianapolis, IN
Posts: 566
Quote:
Originally Posted by zjosh93 View Post
What is your backlash either way? They make a case spreader for the Dana rear end but I never hear about people using it. I suppose using a brass drift works just as well.
I've always heard you can crack the aluminum case if your not careful with the case spreader.
I know I will be chastised for this but I don't have the backlash measurement. I have been successful with factory shims and using the gear pattern with marking paint and the guide in the FSM.

1st gear pattern showed I needed less backlash or to increase shim on drivers and decrease on passenger. The passenger side had a larger shim than drivers so by reversing shims I got the more accurate pattern. It appears the guy at the "reputable shop" didn't even use gear paint. It looks like he tore it apart and threw the parts in a bucket, put in the bearings, did pre-load by "feel" as I hear some do, and then slapped it all together.
__________________
Mine '97 White, ZJ Ltd, 5.2, Up-Country Suspension, Kolak ignition, Kolak/Magnaflow Exhaust
Her's '98 Chargold ZJ Ltd. 4.0 2wd
Our 1st '97 White, ZJ Ltd, 5.2, The parts Jeep for 5 years...R.I.P. Sent to Pic-A-Part 5/17/2013

stageninja is offline   Reply With Quote
Unread 07-23-2013, 02:14 PM   #21
zjosh93
Registered User
1993 ZJ 
 
Join Date: Aug 2010
Location: Austin
Posts: 994
Gotcha, in that case the second gear pattern looks better. I'd go with that arrangement.
zjosh93 is offline   Reply With Quote
Unread 07-23-2013, 02:30 PM   #22
stageninja
That Rigger Guy
 
stageninja's Avatar
1997 ZJ 
 
Join Date: Apr 2007
Location: Indianapolis, IN
Posts: 566
Quote:
Originally Posted by zjosh93 View Post
Gotcha, in that case the second gear pattern looks better. I'd go with that arrangement.
Yes the second pattern is way better. Have the gear paint cleaned up and the axle shafts installed. I'll get a couple photos before I close it up and fill with Lucas 75w-140 + 1 bottle of Mopar Friction Modifier.
__________________
Mine '97 White, ZJ Ltd, 5.2, Up-Country Suspension, Kolak ignition, Kolak/Magnaflow Exhaust
Her's '98 Chargold ZJ Ltd. 4.0 2wd
Our 1st '97 White, ZJ Ltd, 5.2, The parts Jeep for 5 years...R.I.P. Sent to Pic-A-Part 5/17/2013

stageninja is offline   Reply With Quote
Unread 07-23-2013, 03:49 PM   #23
96zedjay
Registered User
1996 ZJ 
 
Join Date: Jun 2012
Location: Cincinnati, Ohio
Posts: 277
Problem w/44a is thermal expansion.... Ultimately you need a tad more carrier preload and endcap crush then an Iron pig would have.
That and Dumb_ss's that jack the rear end up by the center section. Ideally the caps should be torqued into place and measured with a bore gauge then the caps clipped for proper crush spec. If you can get the diff and shims in easily without a spreader or heating the case likely you won't have enough carrier preload. Bottom pattern looks good. Make sure to clean everything. Remember the carrier and axle bearings swap spit in operation so if you do carrier bearings and the axle/axle bearing
is going it with take the other out or vice versa. Make sure the diff is clean inside. After bearing failure the debris has a tendency to get trapped by centrifgal force in the diff. and find it's way out later to trash the new bearings. Worse in trac-locs.
Just my $.05 worth after 40 years experience setting up rear ends.
96zedjay is offline   Reply With Quote
Unread 07-23-2013, 04:47 PM   #24
stageninja
That Rigger Guy
 
stageninja's Avatar
1997 ZJ 
 
Join Date: Apr 2007
Location: Indianapolis, IN
Posts: 566
Thanks. As my post began I started by setting up to replace the wheel bearings that weren't replaced with original rebuild. So yes those are done as well. I did in fact thoroughly clean the diff housing & axle tubes. Including running shop towels w/broom stick until the towels came out clean. After getting it back together I did my 1st 5 tire rotation since buying these tires 6 weeks ago.

Now I'm off for a test drive.
__________________
Mine '97 White, ZJ Ltd, 5.2, Up-Country Suspension, Kolak ignition, Kolak/Magnaflow Exhaust
Her's '98 Chargold ZJ Ltd. 4.0 2wd
Our 1st '97 White, ZJ Ltd, 5.2, The parts Jeep for 5 years...R.I.P. Sent to Pic-A-Part 5/17/2013

stageninja is offline   Reply With Quote
Unread 07-23-2013, 05:30 PM   #25
stageninja
That Rigger Guy
 
stageninja's Avatar
1997 ZJ 
 
Join Date: Apr 2007
Location: Indianapolis, IN
Posts: 566
Just came off the freeway. The roar is gone. The diff cover is not too hot to touch but gets uncomfortable to hold my hand on it for very long. Like 115-120 F or hot water from the tap.
__________________
Mine '97 White, ZJ Ltd, 5.2, Up-Country Suspension, Kolak ignition, Kolak/Magnaflow Exhaust
Her's '98 Chargold ZJ Ltd. 4.0 2wd
Our 1st '97 White, ZJ Ltd, 5.2, The parts Jeep for 5 years...R.I.P. Sent to Pic-A-Part 5/17/2013

stageninja is offline   Reply With Quote
Unread 07-24-2013, 12:57 PM   #26
970001zj
Registered User
1997 ZJ 
 
Join Date: Feb 2012
Posts: 1,865
good thread :twothumbsup:
__________________
[QUOTE=PolkaPower;]96+249's are basically RWD until it slips then the awe kicks in.[/QUOTE]
970001zj is offline   Reply With Quote
Unread 07-24-2013, 06:33 PM   #27
stageninja
That Rigger Guy
 
stageninja's Avatar
1997 ZJ 
 
Join Date: Apr 2007
Location: Indianapolis, IN
Posts: 566
Quote:
Originally Posted by zjosh93 View Post
Are you sure about the shop only taking off 1/2 thousandth from the cap? The caps look like investment castings and it looks like they took enough off the take the crown off the casting. I also don't see how cutting 1/2 thousandth from the cap is going to repair ten thousandths of wear into the housing and cap (5 thousandths on each side). I was looking as the angled section near the end of the cap and it looks visibly shorter than the uncut cap. I'd think you'd need to cut at least 10 thousandths which is about how much that.
After reading this reply several times; the housing was more discoloration than scored by the race. The cap wasn't worn evenly by the spinning race so the 10 thousandths would have been too extreme a correction as it would have created too much fleet angle on the axle as it came into the diff. The 1/2 or as you say maybe 1 to 2 thousandths, in reality, was the compromise to gain adequate purchase on the race w/o distorting or radically changing the fleet angle of the axle. If fleet angle is new to some; it's the term we use in theatrical rigging for the drive path under load. Ie: too radical a fleet angle = bad load path and potentially stuff falling out of the sky and hurting or killing people. Purchase is the grip or friction of one component to another. I am driving to Chicago on Fri. @ 2:am so this will be a real test as to whether this whole rebuild works or not.
__________________
Mine '97 White, ZJ Ltd, 5.2, Up-Country Suspension, Kolak ignition, Kolak/Magnaflow Exhaust
Her's '98 Chargold ZJ Ltd. 4.0 2wd
Our 1st '97 White, ZJ Ltd, 5.2, The parts Jeep for 5 years...R.I.P. Sent to Pic-A-Part 5/17/2013

stageninja is offline   Reply With Quote
Unread 07-24-2013, 06:49 PM   #28
stageninja
That Rigger Guy
 
stageninja's Avatar
1997 ZJ 
 
Join Date: Apr 2007
Location: Indianapolis, IN
Posts: 566
A little out of sequence but here are the photos after inserting axle shafts and c-clips. The second 1 caused me to wipe each gear tooth again
clean_diff_.jpg

clean_diff2.jpg

Tomorrow I will do an oil change before driving to Chicago, just cause it's about that time anyway.
__________________
Mine '97 White, ZJ Ltd, 5.2, Up-Country Suspension, Kolak ignition, Kolak/Magnaflow Exhaust
Her's '98 Chargold ZJ Ltd. 4.0 2wd
Our 1st '97 White, ZJ Ltd, 5.2, The parts Jeep for 5 years...R.I.P. Sent to Pic-A-Part 5/17/2013

stageninja is offline   Reply With Quote
Unread 07-24-2013, 07:52 PM   #29
zjosh93
Registered User
1993 ZJ 
 
Join Date: Aug 2010
Location: Austin
Posts: 994
Quote:
Originally Posted by stageninja View Post
After reading this reply several times; the housing was more discoloration than scored by the race. The cap wasn't worn evenly by the spinning race so the 10 thousandths would have been too extreme a correction as it would have created too much fleet angle on the axle as it came into the diff. The 1/2 or as you say maybe 1 to 2 thousandths, in reality, was the compromise to gain adequate purchase on the race w/o distorting or radically changing the fleet angle of the axle. If fleet angle is new to some; it's the term we use in theatrical rigging for the drive path under load. Ie: too radical a fleet angle = bad load path and potentially stuff falling out of the sky and hurting or killing people. Purchase is the grip or friction of one component to another. I am driving to Chicago on Fri. @ 2:am so this will be a real test as to whether this whole rebuild works or not.
Gotcha! I assumed that your machinist knew what he was doing but I was just curious because things weren't lining up in my head.
zjosh93 is offline   Reply With Quote
Unread 07-26-2013, 01:21 AM   #30
stageninja
That Rigger Guy
 
stageninja's Avatar
1997 ZJ 
 
Join Date: Apr 2007
Location: Indianapolis, IN
Posts: 566
3:20 eastern, headed for Chicago from Indy.
__________________
Mine '97 White, ZJ Ltd, 5.2, Up-Country Suspension, Kolak ignition, Kolak/Magnaflow Exhaust
Her's '98 Chargold ZJ Ltd. 4.0 2wd
Our 1st '97 White, ZJ Ltd, 5.2, The parts Jeep for 5 years...R.I.P. Sent to Pic-A-Part 5/17/2013

stageninja is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.