Trying to fit an aluminium W126 / 107 trailing arm to a W123 - a question of compatib - Page 3 - PeachParts Mercedes-Benz Forum

JamesDean · #31 06-06-2012, 09:15 AM

Quote:

Originally Posted by kerry

Well those rear trailing arms, at least on the 126, seem highly subject to corrosion. Avoiding that problem may be worth it.

TRUTH! Passenger side seems most common. My SD and my buddies old SE.

W126 Trailing Arm / Rear Lower Control Arm Rebuilt & Replacement

Stretch · #32 06-06-2012, 10:39 AM

Quote:

Originally Posted by t walgamuth

The rear calipers on the aluminum setup are floating caliper, similar to the 124 chassis. It looks to me like the conversion is way too complicated for the value offered. (Sorry)

...

I forgot to say about the caliper difference...

I don't consider it to be a problem at all just use the caliper that is designed for the aluminium trailing arm. I haven't checked it out yet but the piston diameters look the same - so I don't expect a difference in braking force.

One of the trailing arms came with a caliper fitted - and if it is OK that could save a bit of cash. It is an ATE by the way... they might all be ATEs for aluminium trailing arms... I don't know I'll have to check with the dealer...

Anyway here are some more pictures.

1) The slightly different although similar looking caliper

2) The anti roll bar connection

3) The shock mounting bits (also no problems there from what I can see)

vstech · #33 06-06-2012, 01:06 PM

bump

charmalu · #34 06-06-2012, 01:30 PM

Ok this Kilo gram stuff means absolutly nothing to me, sooooooooo.........
Since Google is our friend

16KG = 35.27lbs

21KG = 46.30lbs

11.03lbs difference.

Charlie

Stretch · #35 06-06-2012, 01:54 PM

I'm sorry Charlie - I'll try and remember to convert any future measurements into old money as well!

So what do you think of the whole idea then? Would you consider doing it? (for the right price of course)

greazzer · #36 06-06-2012, 02:26 PM

Army,

With this upgrade, can you use the bigger calipers and rotors ? Seems like a nice trade off. I would swap 11 pounds for the bigger and better brakes. I would rather lose 11 pounds off my gut. My .02. So, does this whole sha-bang just bolt in ?

Stretch · #37 06-06-2012, 03:27 PM

Quote:

Originally Posted by greazzer

Army,

With this upgrade, can you use the bigger calipers and rotors ? Seems like a nice trade off. I would swap 11 pounds for the bigger and better brakes. I would rather lose 11 pounds off my gut. My .02. So, does this whole sha-bang just bolt in ?

I don't think the brakes are any different operational wise.

I have to check them out still but the caliper that was left on one of the aluminium trailing arms that I bought looks like it has the same sized brake piston in there as the calipers that are fitted on the steel trailing arms. It looks like only the casting is different so that it fits into the slot on the aluminium trailing arm whereas the calipers on the steel trailing arms just bolt on (as I'm sure you know).

I guess this "upgrade" on a W126 would be very straightforward as you'd just remove and replace. The only problem that might occur would be fixing the thicker anti-roll bar to the chassis for the anti-dive mechanism. But that might not be a problem.

As for doing this to a W123 I know that that anti-roll bar needs to be narrower. The W126 is a wider car. The rest of the stuff seems to me to just be a bolt on job though - I might be able to use a W123 coupe rear anti-roll bar or shorten a W126 one for the anti-dive attachments... I haven't gotten that far yet. (And like I've said I'm not sure if I'll go that far!)

The anti-dive mechanism should in principle be a handling advantage when fitted to a vehicle with a powerful engine - but when fitted to a N/A OM617 I guessing it isn't going to have much of an effect...

...oh yes there's a difference of 5kg / 11lbs per side.

charmalu · #38 06-06-2012, 03:45 PM

That extra 11lbs will give the rear tires that extra downward force to help eliminate Burn Outs.

You know with the Turbo added, helps the 617.952 unleash all that awsome power.

Charlie

Stretch · #39 06-06-2012, 03:49 PM

Quote:

Originally Posted by charmalu

That extra 11lbs will give the rear tires that extra downward force to help eliminate Burn Outs.

...

Right that's it I'm not doing it then!

Stretch · #40 06-07-2012, 07:51 AM

I'm quite lucky having both the W123 ATE and W126 ATE brake calipers to compare. If one set had been of another make it might not be so clear.

I can confirm that

1) the brake pads are the same
2) the discs are the same
3) the brake pistons in the calipers are the same
4) the caliper mounting bolt diameters are the same but the bolts are of a different length
5) the distance between the centres of the mounting bolts are the same
6) only the thickness of the mounting side on the W123 caliper is thicker - the casting is slightly different in this area - that's it.

Here are the pictures

t walgamuth · #41 06-07-2012, 08:46 AM

I am sorry, I am certain that the rear calipers were different on my 84 500sec so assumed that all the aluminum arm cars would have them. Those look to be pretty much the same as on the 123 cars.

Stretch · #42 06-07-2012, 10:19 AM

Quote:

Originally Posted by t walgamuth

I am sorry, I am certain that the rear calipers were different on my 84 500sec so assumed that all the aluminum arm cars would have them. Those look to be pretty much the same as on the 123 cars.

Thanks for your input Tom - I have no idea which W126 these came from - they could in fact have been from a R107. I have no idea and no reliable way of finding that information.

All I did was buy these bits from a bloke selling them on marktplaats (that's a Dutch variation of ebay that's very popular 'cos for lots of stuff you don't need to pay for the advert). In his advert he has a picture showing racks of these parts already removed from the cars - it could be his picture - it might not be! I have no idea. I didn't go and see him - I just got him to put them in the post for me.

I'll spend some time doing a bit more research for part numbers then we'll know what's what.

cmbdiesel · #43 03-11-2013, 03:18 PM

Quote:

Originally Posted by daw_two

I had a set of the anti-squat non steel trailing arms. I sold/shipped them to a guy over in Little Rock but they wouldn't work for his w123 as I recall. I asked him to hang onto them and I'd pick them up sometime when I was in that neck of the woods. I didn't want to pay for return shipment.

Naturally, I refunded his money.

Did you ever get the trailing arms back?
Are they compatible with W126 300SD?

Stretch · #44 03-13-2013, 05:06 AM

Quote:

Originally Posted by cmbdiesel

Did you ever get the trailing arms back?
Are they compatible with W126 300SD?

You might be better off sending a PM for this one.

If you do and you get a replay, I for one would like to know the answer.

vstech · #45 03-13-2013, 06:49 AM

Quote:

Originally Posted by cmbdiesel

Did you ever get the trailing arms back?
Are they compatible with W126 300SD?

the 126 in 2nd gen form has different rear subframe, but it's a bolt in, so installing the arms in a 126 should be fairly simple.
I've seen them on 126 SEC's at the parts yard.