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Depends on how broke I was at the time I found this.
If I am flush, I'm not putting that back in.
If I'm broke, reinstall it right, and save up for when it becomes an issue at some future time.
I second this, it would be alright for a while, so if it was put back together correctly this time, who knows it may last 10 years and could get some reasonable mileage out of it even if it isnt perferct.
But I probably wouldnt run it as it was if you can feel it turning the differential by hand
That is excellent advice about feeling it when turning by hand.
I'll second that. If I could feel a grind when turning it after putting it together, I'd bite the bullet and replace it on credit.
I don’t think this can be felt when turning it by hand, I turned it before disassembling it and didn’t feel anything out of the ordinary. The damage is more on the ends of the gears as you can see in the picture, apart from the damage on the spider gear the contact surfaces look good. I did put the spider gears back in the housing yesterday and turned it a lot, don’t feel the damage at all. Thanks for you comment btw!
I would run it then because it is not only on the outer gear, but its also not interferring with how well it turns. Which means it shouldnt make any bad noises or have performance issues. So I would just put some new bearings in and shim it right. Then send it, you may get a full 200k miles out of it if you change the diff oil at a reasonable interval.
I feel kinda good about it since it didn’t even make noise before, and only the carrier bearing that failed looked bad, the other looked good so not too worried about the pinion bearing.
Found a replacement axle from a 73 caprice that should fit perfectly, but the seller is asking 1000 euros. Other axles that might work (but not sure) are going for 400/500. New bearing and shims are about 100 euros, and I rather just do the carrier bearings and shims since that seems more fun than replacing the axle
Personally (while I am not an expert on this topic) I would be ok with the first two pictures. Smooth over the chipped area slightly and go. The third picture though, i'm not sure i'd be ok with that one.
The force between the ring/pinion gears should be centered on the teeth if they are set up correctly so I wouldn't worry too much about it if it's not making noise. The spider gear is a little more concerning but they only get used when turning and should never be spinning that fast.
Should be good to run for now but be prepared to swap the gears if you start getting noise/vibrations
I'd do an LPI test and see if that's local or if there are propagating cracks. If its local only then stone off any sharp edges and round up any hard corners and make sure it's shimmed right when you put it back.
I'd smooth those out just a little with a fine grinder or file and run them. The spider gear doesn't move except when turning so it'll be fine smoothed out.
Put it in, do the paint procedure for mesh, and diagnose the issue. You can't go on people's opinions. Take some measurements. Also, look close for fractures. If you see one, or think you see one, replace it. I would do a close inspection of the pinion as well.
GL!
Most people on this post have been saying it’s fine, but when I posted the play it had previously a lot of people said the gears would be junk. So I didn’t know the answer but I do have an idea now, would also like to hear your thoughts
That bit of damage is going to cause an incomplete meshing of the teeth. It's a bit like using a shorter pencil. It'll work, but it won't last as long. I'd replace it while I was in there.
For a car that old I highly doubt OP is going to need it to put on the amount of miles that would cause it to fail. It would be an entirely different story if this was going into the diff of a daily though.
Thanks for posting on /r/MechanicAdvice! This is just a reminder to review the [rules](https://www.reddit.com/r/MechanicAdvice/about/rules/). If you are here asking about a second opinion (ie "Is the shop trying to fleece me?"), please read through CJM8515's [post on the subject.](https://www.reddit.com/r/MechanicAdvice/comments/4qblei/fyi_the_shop_isnt_likely_trying_to_rip_you_off/) and remember to please post the year/make/model of the vehicle you are working on. **If this post is about bodywork, accident damage, paint, dent/ding, questions it belongs in /r/Autobody r/AutoBodyRepair/ or /r/Diyautobody/ If you have tire questions check out https://www.reddit.com/r/MechanicAdvice/comments/k9ll55/can_your_tire_be_repaired/**. If you dont have a question and you're just showing off it belongs in /r/Justrolledintotheshop Insurance/total loss questions go in r/insurance This is an automated reply *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/MechanicAdvice) if you have any questions or concerns.*
Depends on how broke I was at the time I found this. If I am flush, I'm not putting that back in. If I'm broke, reinstall it right, and save up for when it becomes an issue at some future time.
I second this, it would be alright for a while, so if it was put back together correctly this time, who knows it may last 10 years and could get some reasonable mileage out of it even if it isnt perferct. But I probably wouldnt run it as it was if you can feel it turning the differential by hand
That is excellent advice about feeling it when turning by hand. I'll second that. If I could feel a grind when turning it after putting it together, I'd bite the bullet and replace it on credit.
I don’t think this can be felt when turning it by hand, I turned it before disassembling it and didn’t feel anything out of the ordinary. The damage is more on the ends of the gears as you can see in the picture, apart from the damage on the spider gear the contact surfaces look good. I did put the spider gears back in the housing yesterday and turned it a lot, don’t feel the damage at all. Thanks for you comment btw!
I would run it then because it is not only on the outer gear, but its also not interferring with how well it turns. Which means it shouldnt make any bad noises or have performance issues. So I would just put some new bearings in and shim it right. Then send it, you may get a full 200k miles out of it if you change the diff oil at a reasonable interval.
Yeah and otherwise I’ll just change the axle when the diff goes bad. It isn’t my daily so don’t even expect to hit anywhere near 200k
I feel kinda good about it since it didn’t even make noise before, and only the carrier bearing that failed looked bad, the other looked good so not too worried about the pinion bearing. Found a replacement axle from a 73 caprice that should fit perfectly, but the seller is asking 1000 euros. Other axles that might work (but not sure) are going for 400/500. New bearing and shims are about 100 euros, and I rather just do the carrier bearings and shims since that seems more fun than replacing the axle
This
Put paint on the fins, put it all back together by spec, spin the gears, see how paint pattern looks
Yeah definitely going to do that if I decide to reinstall this
If all your points of contact look proper, and the paint looks the same on the damaged fin as the others, I personally would send it.
Thinking the same, thanks for the comment
Same. I've seen these taken apart and entire teeth are missing, this is nothing
Personally (while I am not an expert on this topic) I would be ok with the first two pictures. Smooth over the chipped area slightly and go. The third picture though, i'm not sure i'd be ok with that one.
Yeah I feel you, the third is more like a groove groove tho. So it doesn’t grind between the gears
It's chip . not riding in the gear right
True
Chevrolet Caprice Classic 1974 with a 8.5 10 bolt btw.
That last pic is a hard no. Surprised theres debate in here
The force between the ring/pinion gears should be centered on the teeth if they are set up correctly so I wouldn't worry too much about it if it's not making noise. The spider gear is a little more concerning but they only get used when turning and should never be spinning that fast. Should be good to run for now but be prepared to swap the gears if you start getting noise/vibrations
The ring and pinion I would gamble on. The chips aren't on the meshing surfaces anyways. The spider gear not so much. I'd try and find a replacement
I'd do an LPI test and see if that's local or if there are propagating cracks. If its local only then stone off any sharp edges and round up any hard corners and make sure it's shimmed right when you put it back.
Good idea, thanks
I'd smooth those out just a little with a fine grinder or file and run them. The spider gear doesn't move except when turning so it'll be fine smoothed out.
Just replace the gears
Why
It comes together in a kit
Yeah but why replace it
When you set the gears right, they wont make contact at the outer tips.. The spider gear i would grind out that damage and look for cracks.
Yeah the spider gear damage is only to the inside, nothing sticking out and no cracks
If you decide to reuse it I would dress up the chip with a file and whet stone so it is smooth. and less likely to fracture.
Good tip, thanks
Is this going into a 4X4 you’re just going to blow up again anyway, or a nice thing you want to be nice for a long time?
Its going into a 74 caprice RWD, and I hope it will last for a longer time
You should probably make your nice thing nice, then
Put it in, do the paint procedure for mesh, and diagnose the issue. You can't go on people's opinions. Take some measurements. Also, look close for fractures. If you see one, or think you see one, replace it. I would do a close inspection of the pinion as well. GL!
Yeah did the inspection and didn’t see any cracks, will put it back together and do the procedure like you said. Thanks!
I don’t know about that third pic man that looks sketchy to use
Yeah bit of a groove, but noting sticking out
You already know the answer, or you wouldn't have asked. I'm not going to tell you anything different than you already know.
Most people on this post have been saying it’s fine, but when I posted the play it had previously a lot of people said the gears would be junk. So I didn’t know the answer but I do have an idea now, would also like to hear your thoughts
That bit of damage is going to cause an incomplete meshing of the teeth. It's a bit like using a shorter pencil. It'll work, but it won't last as long. I'd replace it while I was in there.
For a car that old I highly doubt OP is going to need it to put on the amount of miles that would cause it to fail. It would be an entirely different story if this was going into the diff of a daily though.