Diff pinion depth on a new(ish) JK
#11
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I used to do a fair amount of differentials and this is the first I have seen that were off like that. They have to be making noise? I think when they are assembled at the plant they have the exact housing specs and can install the right shim to do it quickly and keep the production line going. I'll bet someone changed the setting when installing the Ox Locker. Those gears will have a short life.
I'm actually inclined to believe that they would work... Look at the drive pattern (1st photo). It's not perfect, but it's not a bad shape, a little closer to the toe, which is good. It seems to cut off at the top, but it doesn't really. It actually fades close to the top. It could be a little more towards the root, but as long as it doesn't cut off at the top, it should be fine.
The coast pattern I don't like, but then it's used only in reverse.
Last edited by aro; 01-19-2016 at 10:50 AM.
#12
Former Vendor
Am I the only one who can't open the photos? I can only see the small photo which doesn't help much.
Words of wisdom when looking at patterns (especially used gears): Being centered heal and toe is not a major concern, just make sure that it is well centered face and flank.
Words of wisdom when looking at patterns (especially used gears): Being centered heal and toe is not a major concern, just make sure that it is well centered face and flank.
#13
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I tried the photos in several browsers and they opened up fine. Here is two links to them:
http://i1190.photobucket.com/albums/...psxvzc8tlh.jpg
http://i1190.photobucket.com/albums/...pssibqbtsy.jpg
http://i1190.photobucket.com/albums/...psxvzc8tlh.jpg
http://i1190.photobucket.com/albums/...pssibqbtsy.jpg
#14
There are several variations of patterns that are acceptable. Not just the classic nice and centered on the drive and coast side perfect patterns. On those pics you would expect your coast side pattern to be closer to the heel with the drive side showing closer to the toe like that but its not. It does appear to be a little high on the coast side though. Not all gear sets will setup with perfect patterns, this is why there are acceptable variations. This is where experience comes in. If it is not making any noise and the lash is set correctly I would run it. Just changing the carrier should not have affected the pattern besides having to check and possibly readjust the lash.
#15
Doh!
I get that part, I guess I'm trying to figure out (for my own edumication) how to determine if it's pinion depth or carrier placement that would correct a specific contact pattern, etc. I guess that's why guys go to mechanic's school.
If I had a bigger shop, a heated garage, and some spare pinion bearings to play with, I might consider tackling it myself, if I knew what to do to correct the patterns I am seeing.
I get that part, I guess I'm trying to figure out (for my own edumication) how to determine if it's pinion depth or carrier placement that would correct a specific contact pattern, etc. I guess that's why guys go to mechanic's school.
If I had a bigger shop, a heated garage, and some spare pinion bearings to play with, I might consider tackling it myself, if I knew what to do to correct the patterns I am seeing.
#16
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There are several variations of patterns that are acceptable. Not just the classic nice and centered on the drive and coast side perfect patterns. On those pics you would expect your coast side pattern to be closer to the heel with the drive side showing closer to the toe like that but its not. It does appear to be a little high on the coast side though. Not all gear sets will setup with perfect patterns, this is why there are acceptable variations. This is where experience comes in. If it is not making any noise and the lash is set correctly I would run it. Just changing the carrier should not have affected the pattern besides having to check and possibly readjust the lash.
Usually, incorrect pinion depth shows up at opposite sides/corners. In my pattern, both drive and coast are on the same side, closer to the toe. Just that coast is higher than drive. It could well be the way they were machined, and maybe that's why factory left them like that. Some R&P's can be a pain if you chase a perfect pattern.
#17
JK Enthusiast
I agree, experience comes in handy, especially since my pattern is not quite your run of the mill pattern. I think I literally looked at every pattern that Google can find, and while a few are maybe somewhat close, I couldn't find anything quite like it.
Usually, incorrect pinion depth shows up at opposite sides/corners. In my pattern, both drive and coast are on the same side, closer to the toe. Just that coast is higher than drive. It could well be the way they were machined, and maybe that's why factory left them like that. Some R&P's can be a pain if you chase a perfect pattern.
Usually, incorrect pinion depth shows up at opposite sides/corners. In my pattern, both drive and coast are on the same side, closer to the toe. Just that coast is higher than drive. It could well be the way they were machined, and maybe that's why factory left them like that. Some R&P's can be a pain if you chase a perfect pattern.
#19
There are several variations of patterns that are acceptable. Not just the classic nice and centered on the drive and coast side perfect patterns. On those pics you would expect your coast side pattern to be closer to the heel with the drive side showing closer to the toe like that but its not. It does appear to be a little high on the coast side though. Not all gear sets will setup with perfect patterns, this is why there are acceptable variations. This is where experience comes in. If it is not making any noise and the lash is set correctly I would run it. Just changing the carrier should not have affected the pattern besides having to check and possibly readjust the lash.
Both being on the toe like that usually means add a little backlash in my experience, but you said you are already on the loose side. I'd run them like that and both think twice.
#20
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Here is another pretty lousy factory pattern from this forum: https://www.jk-forum.com/forums/modi...attern-266900/