Rear end differential grinding noise

transmissions

#1

I bought this van (1995 chevy van 20) last year and the rear end made some sounds but not as bad as its now.

So, after buying it I decided to open up the rear end and inspect for any damage to suggest it needs repairs. No signs of metal chips, nicks, or any wear on the bearings and gears. After a while of driving it I decided to remove the carriage and pinion from the rear end to give it a close inspection.
After doing this and finding no clear sign of war or damage, i decided to replace the carriage barrings to see if that made a difference.
After placing the new bearings back on the carriage, pinion back into the rear differential, and trying to do it all by myself, i lost the marks i had placed on the carriage bolts and clamps since I had little time to get it back together. After that I had no other choice but to place the clamps bolts where i could estimate they belong. I was done, then drove it and some of the noise went away but a grinding sound on decelerating emerged. Well, now that sound is gotten worst and its more like a grinding sound.
I can assume that not placing back the bolts and carriage clamps back changed the position of the carriage relative to where it was, but am not 100% sure. how can I correct the positioning of the carriage? if that is not the issue what test can i perform to find the culprit?


#2

Aside from mixing up parts in the rear diff, did you follow any of the procedures shown in this video?

Tester


#3

You have to adjust this stuff on reassembly ,with shims and what have you ,iDidnt watch the Vid ,but Tester knows how important this is ,the wrong clearance and the whine and howl will drive you nuts .


#4

I would look at ujoint.


#5

No I didn’t do it like the video shows because I didn’t touch the pinon gear assembly since there was no signs of wear. The only thing I did was remove the carriage assembly from the axle, like the video shows, didn’t remove the ring gear, but I did removed/replaced the carrier bearings since there was some wear. I lost the markings on the carrier straps and bolts. Now the differential has a grinding sound that is getting worst. what could be the issue/


#6

In your original post, you stated that you removed the pinion and carrier from the diff.

Did you or did you not remove the pinion gear?

But it really doesn’t matter.

Since you mixed up the carrier bearing caps for the carrier, the diff will probably need to be rebuilt the proper way.

Either that, replace it with a used unit from a local auto recycler.

Tester


#7

Did you replace the crush sleave?


#8

I removed that stuff on my truck one time to replace the limited slip clutches, reinstalled the works with no problem. Maybe it is simpler w/a Ford 9 incher for some reason.

I’d have guessed you would have seen the reason for the noise though, with everything on the work bench. No signs of worn edges on the gears, chips of metal missing, etc? … hmmm … if you are certain the noise is coming from the differential and not the wheel bearings, take a close look at the ends of the axels, where they insert via a spline mechanism into the differential innards. Those splines can wear and cause weird noises too. I was riding in a station wagon to go camping at Yellowstone one time, and we started hearing weird noises back there. So we had to pull into a shop and ask for help. The shop was able to fix it without much difficulty just by dressing up those axel splines.


#9

A Ford 9 inch has a removable carrier ,which helps some ,the “the pumpkin head” assembly on a Ford is one of the auto worlds better designs ,very interchangeable also …
A GM 10 bolt doesnt seem to be as durable (I am assuming that is what this van has in it) the fact that it was noisy ,seems to indicate it was starting to develop problems anyway ,try to find a good used one ,is my advice . Someone else may have run this unit low on oil .


#10

Sounds like your pinion bearings are going bad. They can “feel” OK and still make noise.

Its gotta come back apart and be assembled correctly, with new bearings and a new crush sleeve. Maybe even the carrier bearings, too, if the misplaced caps have damaged them. You should be able to see mis-matched caps on the carrier bearing races - the wear pattern will not be even.


#11

Most locales with sizeable population centers have auto repair specialist shops that do this kind of work every day. Repairing drive line stuff – drive shafts, u-joints, differentials, transfer cases, axels, axel bearings — that’s what they do, that’s their business model. So one idea is just pack up the unit and take it to one of those shops. It does’t matter that the OP lost the reference marks. They deal with that problem all the time. They’ll know how to put it back together, and how to diagnose it. I’ve never had to use one, but I expect they appear in the yellow pages.


#12

I would check out the price of a replacement unit from a salvage yard first.


#13

At leas the OP thought they could save a couple bucks.


#14

Tester I removed the pinion gear from the rear end housing but did not disassemble it since I didn’t have a press. Didn’t replace the crush sleeve because i didn’t disassemble the pinon gear/bearing assembly. I’m going to take another look to see if I see any metal chips or wear but I suspect the van is going to need a newer or rebuild rear-end since it has 196k miles on it. If i get it from a salvage yard, should I get the entire rear end? or the carrier/pinion set?


#15

Save yourself a whole lot of trouble and replace the diff with a used unit.

Tester


#16

Hub to hub.


#17

My vote is with the above; a complete unit from the boneyard. Around here a used one is about 125 bucks; complete.

The Pull A Part around here used to get 50 bucks but have now decided they’re worth a 100 + core and you have to wrestle it out yourself. It’s not worth messing with.


#18

My vote is with the above; a complete unit from the boneyard. Around here a used one is about 125 bucks; complete.

Have you priced one lately? Last year a neighbor blew the rear end in his 2006 F150. The ring gear bolts backed out of the carrier. I gave him a price for me to build a replacement. He thought maybe a good used was the way to go. Couldn’t find one for less than $600. For that price he just paid for me to rebuild his with new parts.


#19

20 yr old van? U paid <$1k? Rebuilt Rearend might cost more. Time to replace van.