Next week I'm helping a friend with some brake work on a '91 300E. I don't have the specs for new/minimum front rotor thickness - have the rear data since the rotors are the same as my 201.

Anyone have the 124 front rotor new/minimum thickness specs that they can post?

Duke

I don't have my service manual handy right now, but the min. thickness should be stamped or cast into the rotor itself. If it's stamped, it's possibly on the circumferential face. You might have to remove some corrosion in order to read it.

Haynes manual is showing 22 new and 19.4 minimum for ventilated, 12 new and 10 minimum for solid - not sure which you have.

I think your quoting from the 190E Haynes manual(?)

I'm looking for the data on the US Spec 300E rotors that I assume are somewhat thicker than the 190E vented rotors, but I'm not sure.

Duke

Front rotors for a 300E with M103 engine and single piston floating calipers are 284mm dia.
New thickness 22mm. Wear limit thickness 19.4mm.

__________________
107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.

Thanks, Greg! Those are the same new/min. thickness as my 201/six, but I think the 300E rotors are greater diameter.

Duke

Nope, 124 manual - 284 mm, 22.4, 19.4 - same numbers as Greg. What makes you think the 300E rotors are bigger?

Well, I think we have established that the 201 vented and 300E rotors are the same thickness.

The part numbers are different so I assume they are different diameters. You both quoted 284 mm for the 300E rotor diameter. I don't have a diameter spec for the 201 vented rotors, but the 201 solid rotors are speced at 262 mm diameter, and I'd be willing to wager that the vented 201 rotors are the same diameter.

Duke

Many brake parts (indeed many parts) are common to both the W201 and W124. Look at this list of brake rotors and note similarities. For this reason there are many brake upgrade options for the W201s and smaller engined W124s.


Front Rotors:

W201 diesel and petrol up to 2.0:
solid 262 x 11 (limit 9)

W201 2.3 & 2.6:
vented 262 x 22 (limit 19.4)

W201 16 valve:
vented 284 x 22 (limit 19.4)

W124 excluding 3.0-24V, 3.2, 4.2, 5.0, some diesel:
vented 284 x 22 (limit 19.4)

W124 3.0-24V, early 3.2 & 4.2:
vented 295 x 22 (limit 19.4)

W124 late 3.2 & 4.2:
vented 294 x 24 (limit 22.4)

W124 some diesel models:
solid 284 x 12 (limit 10)


Rear Rotors:

W201:
solid 258 x 9 (limit 7.3)

W124 excluding wagon, 3.0-24V, 3.2, 4.2, 5.0:
solid 258 x 9 (limit 7.3)

W124 wagon, 3.0-24V, 3.2
solid 278 x 9 (limit 7.3)

W124 4.2:
vented 278 x 24

__________________
107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.