AWD - Successful Bevel Gear Rebuild

Volvo AWD V70-XC70 Forum

INDEX FOR 10/2019(CURRENT) INDEX FOR 3/2018 V70-XC70 INDEX [<<]  [>>]


Successful Bevel Gear Rebuild V70-XC70 1998

Hello all,

I have great news to report.

I started down this long road some time ago when I pulled my bevel gear to be 'inspected' and the trans shop cut all the bearings apart and ruined it. I then started the process of researching for a DIY rebuild. And I can report to you today that I've done this successfully.

First let's start with the 'exploded view' diagrams I found.

From somewhere (???):

1998 VADIS :

2001 VADIS :

2003 VADIS :

You can see from the images that they show different levels of detail and some of the diagrams show things not seen on others. I was working on a 1998 car so I was only guessing that the info on the diagrams for the newer models would work out to be the same or close enough for my application. As it turns out this was mostly a safe assumption.

Here's my final parts list, including the cross reference to the various diagrams:

|------- diagram # ---------|
??? 1998 2001 2003 Part Description OEM # Manufacturer #
Bearing - Main Shaft Side #1 SKF 32010X
Bearing - Main Shaft Side #2 SKF 32010X
2 Bearing - Pinion - Inner 183841 SKF HM89449
3 Spacer 3502104
4 6 14 Sleeve - Collapse 8689678
5 Bearing - Pinion - Outer 183839 SKF M86647
6 7 5 7 Seal - Pinion - Outer 9183891
7 8 Collar - Pinion 9143889
8 9 2 8 Flange - Pinion 9183961
9 2 15 Seal - Thru Axle - Pass Side 9143885
10 3 3 3 Seal - Main Shaft - Pass Side 30735126
11 4 12 4 O-Ring - Main Shaft - Trans Side 977023
12 6 7 6 Drain Plug 6549308
13 5 10 5 Crush Washer (Same as oil drain) 11998
14 15 Seal - Trans - thru axle 9143885
3 3 Seal - Main Shaft - Trans Side 30735126
13 O-Ring - Main Shaft - Trans Side 976041
10 8 9 Lock Nut - Pinion 3549685
19 Collar - Trans to BG 9495034
18 Seal - Trans - Outer Collar 9496129
Bearing Cup - Pinion HM89410
Bearing Cup - Pinion M86610

I didn't buy the pinion collar (9143889) or pinion flange (9183961) as there did not appear to be anything wrong with my originals.

I didn't replace the Trans to BG collar (9495034). This is the piece which transfers power from the trans to the gear and other sites report its high failure rate, but mine showed none of the signs of failure so I reused it to save the money. It won't be the end of the world if I have to go in and replace it later as it doesn't require replacing any seals or anything like that - you just take the BG down and pull it out.

I also didn't replace the pinion bearing spacer (3502104) or the pinion collapse sleeve (8689678). I had a buddy who is a heavy equipment mechanic (marine, trucking, gen sets, etc) who has some experience rebuilding gear boxes and differentials, and he said that he has gotten into the habit of NOT replacing the collapse sleeve unless there are very very good specs on exactly how to do it and to what torque, etc. I did BUY a new collapse sleeve, but I bought it before talking to him about it. This part was very hard to come by and I had to wait for ~4 weeks to get it - the dealer parts guy told me there were only 2 in North America...

Incidentally, there is another bearing spacer for one of the main shaft bearings (32010X) as well, but it's not listed on any of these diagrams.

I didn't replace the drain plug (6549308) and I used a crush washer from my oil change stock (this crush washer is very useful on these cars - oil drain plug, trans drain plug, bevel gear drain plug, rear diff drain plug - WOW!).

I didn't get a new pinion lock nut (3549685) but I SHOULD have. I understand these are not supposed to be reused. Because I didn't have a new one, I used the old one. It seems to be working fine.

I did replace the main shaft trans side o-ring (977023) but I don't think it was necessary. The old one was in great shape and it doesn't seem like it's actually used for 'sealing' anything, it just provides a rubber cushion for the trans to bg collar (9495034) so it doesn't harshly bump up against the actual internal bevel gear main shaft oil seal (30735126) which does the actual sealing. There is another o-ring that seems to perform the same function on the other side in the trans, and it probably is the same part #.

There was some confusion about what seal to use around the outside of the trans to bevel gear power transfer collar. Originally the dealer sent me a 8636194 but it was too big (by millimeters). You'll notice that is the seal listed for the newer model years. When I called again the parts guy was finding it hard to make out the diagram in VIDA but he did end up sending me the right seal (9496129). Your mileage may vary on this one.

I got the main shaft bearings ( SKF brand, paid ~$40 CAN) at a local bearing dealer. I paid a bit more for them there than I would have online (Rock Auto, FCP, others) but I didn't have to pay shipping and that ended up making the cheaper locally.

Same deal on the pinion bearings, but those ones were available from Timken ( still a very good brand but cheaper). The pinion bearings needed the inner 'cups' ordered separately and these part numbers were not readily available from the Volvo literature. I had to actually read the numbers off the old 'cups'.
- HM89410
- M86610

Some of the old bearings came off quite hard even after soaking in penetrating fluid for weeks. BIG bearing pullers are needed and a vice and a nice set of cold chisels will be required, as well as a steady hand. Firm, not brutish force. All the bearing mating surfaces were cleaned thoroughly and lightly sanded before putting the new bearings in place.

All bearings fit on using the standard heat-to-expand and freezer-to-shrink methods. Anything that needed to shrink was put in the deep freeze and anything that needed to expand was put in the oven at ~300deg. You don't need to worry about damaging anything in the freezer, but you can melt the bearing cages and start to overheat the fine bearing surfaces if you get them too hot so don't go over 300deg.

Turning the 'crown ring' was very hard to accomplish. This is the strange 'nut' that fits into the pass side of the bevel gear that provides the tension on the main shaft bearings. We fashioned a piece of metal so that it had a two pronged 'fork' on one end and a 'slot' in the middle so that the 'fork' would fit over the crown bits on one side and the slot would fit over the crown bits on the other side and the 'handle' bit would protrude past the end. This allowed us to strike the 'handle' and apply force to 4 crown bits at once. There are probably any number of tools you could build for this but do build something - beating on only one 'bit' at a time WILL break them off (happened - luckily the o-ring is directly behind it and our break didn't protrude past the o-ring). This should be soaked with penetrating fluid to lubricate the o-ring so that it will slide more easily. When reinstalling we couldn't get the crown ring to turn, until we lubed it with silicone and then it spun right away. Get some lube in there for taking it off and lube it up with silicone for assembly.

The crown-ring o-ring was COMPLETELY toasted on mine. Brittle and stiff. It was leaking a bit before and I can see why. The new o-ring will be much better.

There is no traditional 'gasket' between the two halves of the case, and a sealant needed to be selected. A local company sells Loctite products and we found one for "aluminum flanges" which my experienced buddy recommended from his marine experience. I no longer have the bottle, but from a quick search online it looks like maybe it was Loctite 518?? Your local supply company will be able to help you out with this. The main point is that it is a THIN sealer. I was going to use a silicone sealer like what might be used for forming DIY oil pan or valve cover gaskets, but I have been informed that this approach would have made a gasket that was too thick. Or perhaps it would have squished out from in between the case halves completely. At any rate, there are products out there for sealing cases like this, and we used an anaerobic Loctite flange sealant product, something like (though possibly not actually) Loctite 518.



I have over 100 miles on the newly installed BG and I just reinstalled the prop shaft today with no noises or vibrations at all, so it seems like everything has gone well. I hope I get lots of service out of this thing now.

The Trans shop wanted ~$800 to do this job - parts and labour.

I got all the parts (including the ones I didn't use) for ~$250.

All the original bearings were SKF and all the original seals were NOK. My local bearing supply company could source all of them for me except the strange trans collar seal (9496129) which had what looked like a valid NOK number on it but didn't actually show up in there system, which is why I ended up getting it from the Volvo dealer.

I hope this helps someone else out there. These boxes ARE re-buildable and this job IS DIY-able.

1998 V70 AWD->FWD Turbo 200k+


New 5 Successful Bevel Gear Rebuild [V70-XC70][1998]
posted by  jadnhm  on Sat Sep 18 16:01 CST 2010 >

Cut and paste link:

<< < > >>

Users marked in green are currently online.

©Jarrod Stenberg 1997-2016. All material except where indicated.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.

All participants agree to these terms.
Powered by Denizen - Custom Software for Enthusiasts