I did the early (81-85) W126 brake upgrade and yes, it is a bolt-on operation. The car stopped marginally better, and the brake discs would not overheat and warp like the solid ones. People have swapped the second generation, double-piston W126 calipers (plus larger ventilated discs) in the W123 with success and a strong difference in performance –I do believe they just need to replace the dust shield, but I would install the upgraded booster and master cylinder.

Keep in mind: if you go for this upgrade, you will need 15'' wheels as MINIMUM, so you will not be able to revert to the good ol' bundts.

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[GONE] - 1995 Mercedes E300 Diesel - 130k miles - Smoke Silver (702) over Mushroom leather (265) - Bladder blasting, coast-to-coast work machine.

I have 16" CLK rims on my 300D so the space isnt a concern. One of my rear calipers is leaking pretty badly so I figured why replace it with a stock setup if I can get bigger better brakes on the back for now. I'll do the front's later. As of now I've got the calipers off and one of the rotors, I need to figure out how to get the dust shields off. before I roll out today i'm going to measure my rear rotors to see if the rears are bigger on the w126 and if so I'm going to have to get the shields off the boneyard car. Depending on what they want for the rotors I may just leave them and put on new rotors and pads.

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-SpecialDelivery
1985 300CD Silver/Blue H&R Suspension (Sold, still cryin over that)
1982 300SD Silver/Blue '85 OM617 (Sold)
1982 300D - Blue/Blue (Sold)

There is no difference between the W123 and W126 rear Rotors.
This upgrade to the W126 Rotors, Calipers and Dust Shield is for the front Brakes.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Ahhh thank you Charlie!!! So then I can not use the rear calipers I pulled from the 87 420SEL on the 300D I notice the hose set up is different. or can I ?

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-SpecialDelivery
1985 300CD Silver/Blue H&R Suspension (Sold, still cryin over that)
1982 300SD Silver/Blue '85 OM617 (Sold)
1982 300D - Blue/Blue (Sold)

They are the same rear Calipers on the 87 SEL and the 85 300D.

The rear Rotors are the same from a 76 W115 to the 87 SEL.
May go back earlier and maybe up to 90 in the W126. I just searched in the catalog for those years models.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

the calipers I pulled off an 87 420 SEL yesterday are different from the calipers on my 82 300D, again this is rear, not front

__________________
-SpecialDelivery
1985 300CD Silver/Blue H&R Suspension (Sold, still cryin over that)
1982 300SD Silver/Blue '85 OM617 (Sold)
1982 300D - Blue/Blue (Sold)

different how? different brand perhaps? what size are the rotors themselves? vented?

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Look in the catalog tab at the top of the page. search for 87 420SEL and your yr 300D for rear brake Rotors and rear Calipers. that is what I did to come up with the info I posted.

Maybe one set of calipers are Bendix and the other are ATE?

Mercedes use the rear Rotors for well over 20 yrs on various chassis models,
w114/115, w116, w123, w126 and maybe more.

The Calipers are the same between the 123 and 126.

Charlie

__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

different as in on the 300D calipers the rubber hose screws directly into the caliper....on the 420SEL caliper a short metal hard line is between the caliper and the rubber line

__________________
-SpecialDelivery
1985 300CD Silver/Blue H&R Suspension (Sold, still cryin over that)
1982 300SD Silver/Blue '85 OM617 (Sold)
1982 300D - Blue/Blue (Sold)

so... the calipers are the same, but the hose connects differently...?

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Well looking in the catalog again, and looking up the brake hoses, they are the same part# for both chassis. 126 428 03 35.

The metal line might have something to do with the rear suspention, to clear something. the W126 86 - 91 are refered to as the second generation. the 81 - 85 first generation. there were changes to the rear suspention on the 2nd Gen.

So it looks like you are good to go with the calipers you have.

Charlie

__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

I dont know...I think the female fitting on the caliper which is fitted with the hard line is too small to accept the male fitting on the hose....

now usually thats a great problem to have...but in the case of metal...ROFL

__________________
-SpecialDelivery
1985 300CD Silver/Blue H&R Suspension (Sold, still cryin over that)
1982 300SD Silver/Blue '85 OM617 (Sold)
1982 300D - Blue/Blue (Sold)

Bumping this thread to relate success stories. I have successfully upgraded an 85 300TDT and a 77 300D to W126 front vented discs/calipers. I did not change the dust shield on either and do not have any issues so far.

Just a note that in 77 there were two types of front brake hoses: early and late. the only difference is the diameter on the female end, thread size is the same. early 77 inner fender clip has a smaller diameter. Not sure what prompted the change but the early ones are harder to get.

Another issue I ran into was the inner wheel bearing. The new ones were just a hard too small in diameter to fit on the spindle. Luckily the old bearings were not very old and in good shape.

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rescued 1985 300TD-T, currently rebuilding motor
1977 300D

You must have used first generation W126 Rotors?
With first gen. you can stay with the 14" wheels.

Interesting about the Wheel bearings. First I had heard this mentioned.
I wonder if the early 77`s were using Calipers and Hoses from the W114/115 chassis cars?


Charlie


sent from my pos computer

__________________
there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

I'd be interested in second generation W126 setup; what year was this put in place?

__________________
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1998 VW Cabrio
2001 Audi SomeRoad A/T (no air suspension)
2003 Audi DeadRoad M/T (no vroom, for later)
2002 Audi NoRoad A/T (nothing under the hood, being rebuilt)