Rear wheel bearings

[jeffsandoval]

I read several threads on this forum about changing the rear wheel bearing. I pulled the right rear axle shaft and according to the Haynes manual there should be a circlip on this side. I pulled the shaft out without any resistance and looking at the end of the shaft there is no clip. I am not sure if this is right. Looking for a little help. By the way it had the ball bearing on it not the roller bearing. I have attached a pic of the end of the shaft. I would think it would have a groove in it for the clip.

[ja17]

If you had a clip, you would have a groove for it. The photo did not come through.

[rutger kohler]

I would be very interested in others comments on the right hand rear axle removal and replacement as well.  Like you, I read the Haynes manual and whilst the removal sounded tricky, the replacement sounds even worse with having to jacking the two rear axle ends up into an acute angle to get the circlip to click back in.  i spoke to a mercedes mechanic at the recent canberra (Australia) 50th celebrations and he said there wasn't a circlip on the 280SL covered axle units, and there was no need to jack both the rear axle ends up either? Who is right?

[tel76]

The 1968  280sl that I have just completed did NOT have a circlip, but the 1970  280sl that I am working on HAS a circlip.
It is not a very difficult job to re-fit the axle shaft.
Regarding the bearing some previous cheapskate fitted the wrong bearing, you should go with the correct roller bearing.

[Larry & Norma]

My 1970 280 did not have a circlip.

[jeffsandoval]

I have a pic of the shaft and I will attach it when I get a chance. On the subject of the bearing I get alot of my parts from Millers Mercedes and Buds Benz. I talked to Buds Benz yesterday about ordering the correct bearing and he told me all they sale is the the ball bearing for both side because the roller bearing is not necessary. If that were true why did Mercedes use the roller bearing in the first place. I went to my local dealership and ordered the correct one. Thanks for all the comments. It sounds like it may not be a standard item to have a circlip.

[rutger kohler]

Interesting about the right "right" wheel bearing. Again the mercedes mechanic I spoke about in an earlier post said that the 280SL didn't have the roller bearing, that was for the following model that came out with the V8 engine.  SLS now don't have the roller bearing available and a local supplier also said that they don't supply it either because people just use the ball bearing.

[jameshoward]

Hi, Rutger,

I think your mercedes mechanic is quite wrong. The car should have the barrel roller bearing on the right. Some cars with greater torque (jump in an expert, please) had 2 of these bearings, one on each side. But certainly the correct bearing for the right hand side is the barrel roller. I have, as a stop gap, used the standard bearing for the right when my car developed some play last year (the post is on the site somewhere) but I did this to save money knowing that I was preparing to change over to a 3,46 rear axle from a car with a much larger engine, which had barrel roller bearings on both sides. I am thoroughly enjoying the process of changing the axle at present.

SLS are pretty hit and miss in many areas. I'm often amazed by what they don't have. Can't be a great business model to list a bunch of stuff you don't sell. Anyway, go to MB direct. They have the barrel roller bearing readily available (just picked one up yesterday). It isn't cheap at 69 euros after tax and before any discount, but it's the correct part. (For the bearing spotters - as I've become in the past 72h - there is a difference in design between the old barrel roller, which had a metal brace holding in the bearings, and the new one, which has a plastic clip. Progress... .) For a pagoda, the left bearing is a standard ball bearing, which is a 6208/C3 (thank you, Naj. This is the standard denomination, rather than a MB part and any bearing shop can order it for you). I finally ordered one today for £9 plus shipping. It's not expensive. See here for a bit more: http://www.sl113.org/forums/index.php?topic=17987.0

Dan and others on the forum have posted their views on the woes of using the wrong bearing on the right hand side. There was a discussion about this when I did my stop-gap maintenance measure to get me to the 2012 Euro event. I'm pleased to say any catastrophes were avoided, but on the 'new' axle I will use the correct bearings (maybe both barrel rollers, as one of the ones out of the donor axle looks perfectly good).

Finally, the circlip on the axle half thing isn't a problem nor is it difficult. Just follow the procedure set out in Hayes or written up by several members here on the site. Fortunately, I don't have the circlip on either axle!

Knee deep in bearings.

[stickandrudderman]

SLS are pretty hit and miss in many areas.

That's because they can no longer source parts direct from Mercedes. I have posted at length on this subject before.

[jeffsandoval]

Here is the pic of the axle shaft as you can see there is no groove for the circlip. That being said I would assume mine did not come with it.

[rutger kohler]

Ok, you have given the bearing designation for the lefthand ball bearing (6203 C3), what is stamped on the righthand bearing.  There is no way MB are in the business of making their own roller bearings, this has to be from a roller/ball bearing manufacturer such as SKF, NTN etc.

[jameshoward]

Ok, you have given the bearing designation for the lefthand ball bearing (6203 C3), what is stamped on the righthand bearing.  There is no way MB are in the business of making their own roller bearings, this has to be from a roller/ball bearing manufacturer such as SKF, NTN etc.

I don't know. But you could find out and post the info here...

I'll take a look at one I've got later and see if the info on the bearing helps.

[George Des]

The roller bearing is an SKF self adjusting bearing. I don't have the number handy but I may have the old bearing in my stash of stuff in the garage. You may be able to source it through either an SKF or FAG supplier if you can't get at a local MB dealer. I went through this several years ago using the ball bearing that is used on the other side and after much research ended up tearing the axle back down and replacing it with the proper roller bearing. Much discussion on this and best to use the right bearing in spite of what some mechanics may say. As far as the circlip goes, this is not present on any of the drum brake axles I've dealt with i.e. those on the 230SLs. Hope this helps.

George

[mdsalemi]

6203C3 is a common part number for SKF and Toyo, at least.  Should not have a problem finding it; it was listed in the SKF interchange catalog.  The part should be 6203-J in the common SKF catalog.

The vernacular translates to "Single row, light metric, 17MM bore, steel cage"

While I agree that "there's no way Mercedes in the business of making their own bearings" there are plenty of times when an automotive manufacturer will command a special part, which could be completely custom or simply a modification of existing parts by using different materials or techniques.

http://www.skf.com/binary/12-66347/457013_tcm_12-66347.pdf?WT.oss=6203C3&WT.z_oss_boost=0&tabname=All&WT.z_oss_rank=1

[Benz Dr.]

You can buy a double row ball bearing, self aligning, that will fit in there prefectly - don't use it! This bearing is for high speed aplications and the proper barrel roller bearing is designed for low speed and heavy load.
 Use the proper bearing or you can damage your axle. I have a regular source for these bearings and while they're not cheap, I know they're the right ones to use.

[UJJ]

Hi everybody.

I just did the bearing replacement and all seals this winter (hibernation season if you live in New England) on my '68 280 SL.
I guess we have a little confusion when it comes to the proper bearings and perhaps I can help:
Here are the bearings you'll need; they can be obtained using the description below:

The left hand bearing is a standard "deep groove single row ball bearing - DIN 625 - 6208" ID 40mm x OD 80mm x 18 wide. (Open - no seals)
The right hand bearing is a "single row spherical roller bearing - DIN 635 - 20208" - Same dimensions as the left side.

 DIN stands for = Deutsche Industrie Norm (German industrial standard)


Even though the standard ball bearing will fit on the right side as well, the spherical (also commonly called self-aligning) bearing is required because the pivot point of the right side swing axel is not in line with the pivot point of the drive shaft.
If the same ball bearing as on the left side is being used on the right side it will not last long since it cannot take the misalignment forces onto the outer race that the swing of the axle causes due to the offset of the pivot points.
In other words: the outer race of the bearing cannot be fixed - therefore a spherical bearing is required.
I was able to obtain both bearings from my local bearing supplier using the above descriptions without any problems; however, the spherical bearing took a couple of days to come in and did cost around $80.00 if I remember correctly 

I also have no retaining rings (circlips) on my shafts. I do not see any purpose (at least not in my car) for them since the inner race of the bearings is retained on the shafts with the spanner nut and the outer race by the parking brake mounting plate, thus nothing can move.

Furthermore, the right side shaft has to be able to move in and out slightly within the splined bushing anyway due to the same reason of pivot off-set.

After all it was not such a difficult job to do. I did not need any shaft removal fixture; I just used a slide hammer for the removal of both shafts. For the installation of the new radial seals I used an appropriate size socket and a hammer. However, since the outer race of the right side spherical bearing can tilt during installation it needs to be kept aligned properly to slide back into the bore of the tube. I used a punch to straighten out the outer race through the bolt holes of the brake mounting plate while pulling the whole thing in with the plate mounting screws.
Don’t forget to pack the bearings and the tube cavity with grease before the installation.
Hopefully this helps a little….

Glad to be part of the group, Urban

[mdsalemi]

Urban,

Thank you for an incredibly detailed and insightful experience.

I would surmise from your experience and description, then, that the bearing 6203C3 as described by Rutger Kohler is probably not the correct bearing, as this does not match the two you describe.  This should probably be a lesson for all of us, that just because something fits and works, doesn't mean it will work well or for long, or is correct...and you never know what you will find, pulling out the work of the PO!

[jameshoward]

Michael,

Just a point upon which I may have misled folk on a separate post. 6203 would seem to be the wrong bearing for the back axle (I mention this because in my post about the axle swap this issue arose). 6208/C3 is the correct bearing for the car, but only for the rear left side. It's a standard ball bearing. Don't buy it through mercedes unless you want to pay 3 times the price. I got one today for 9 euros. It's about the same in pounds at home and I imagine is about the same in the Americas. I don't know what 6203 is, but it would not seem logical to assume it's the same as 6208, given that 6202 is about the size of a cotton reel, (I know because I ordered one by mistake this week).

20208 is the designation for the right hand bearing. The FAG brand - with a nylon (polyamide) cage - is Part No 20282-TVP. This IS the bearing supplied by Mercedes in a Mercedes box to me this week (as I noted somewhere, the nylon cage has replaced the steel cage that was on my older bearings). However, the bearing place I've been using charge even more money than Mercedes for the part (£94 as opposed to MBs 69 euros). Here's the data sheet for the bearing. No idea what most of it means, but the bearing guys sent it to me.

James

[UJJ]

Michael
You got that right! Pulling out the work of the PO is like pulling out hair (at least sometimes and of course if you got any).  Nobody does a mistake on purpose unless a few bolts are missing you know where….
The bearing 6203 C3 is a mistake. That would be ID 17mm x OD 40mm x 12mm wide. Obviously not a big mishap since it is impossible to install anyway, so no harm possible. I kind of would feel very uncomfortable to drive around with a drive shaft that small.
Just if somebody is interested and/or is not familiar with, here for what it’s worth:
The C3 specification is the tolerance of manufacturing (quality). In this case C3 which is the most common or standard quality. It usually is not required to specify unless a closer tolerance (higher quality) is required for example C2.
Hibernation is over; I can be spotted driving around in New England. 
Appreciate all of you, great site, Urban

[rutger kohler]

Guys, thanks for all the discussion.  Perhaps I should mention why i wanted the RH rear axle bearing designation.  If I order parts from Europe or the USA the shipping cost is often as much as the part, it is extremly expensive unless you are ordering a lot of parts.  getting a bearing from a local supplier is much more economical.  I respect and agree with others are saying about fitting a roller bearing, however as others in this thread have mentioned the RH rear axle bearing is a fairly standard bearing and as long as care is taken selecting it the replacement should be fine.

[GGR]

I also have no retaining rings (circlips) on my shafts. I do not see any purpose (at least not in my car) for them since the inner race of the bearings is retained on the shafts with the spanner nut and the outer race by the parking brake mounting plate, thus nothing can move.

Furthermore, the right side shaft has to be able to move in and out slightly within the splined bushing anyway due to the same reason of pivot off-set.

The shaft is engaged into a splined part which itself moves freely inside the joint. The clip on the shaft is to ensure that both splined areas are 100% in contact (ie that the moving splined part is not half desingaged). This may not be too much of a problem on lower torque models but it is on higher torque models like the 3.5, 4.5 and 6.3 as forces may be distributed over only half the surface and the moving splined part ends up cracking. This is a very common problem on higher torque models even with the clip. Worst case scenario is that all the little rolls inside the joint go loose and you end up with a nice rear end mixed salad.

[saltima]

I could use some help. I have a 1968 250sl with a winding noise from the rear. I guessing its the rear bearing. I have the rear drums off but i am unable to pull the shaft out. I tried the hammer action as posted here but still no luck. It seems like the shaft is stuck. Any thoughts on getting the shaft out or alternate method?

[Tomnistuff]

I just looked at my `67 230SL right rear outboard bearing.  It`s a FAG 20208, self aligning bearing.  I too, do not have a circlip on the inboard end of the right axle.
Tom Kizer