you never want to use brakes that are not matched same on each axle.
BOTH rears need to be the same, or Both Fronts, it's not important that front and rear match.
so to answer your question, NO do not just put the one ate on with the existing bendix in place.
you need to either rebuild your bendix and put it back, or order another ate so you have a matched pair on your rear axle...

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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!

Its ok to use calipers from different manufacturers for the rear axles. Thats according to FSM 42.4-120/3

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'85 300D Cal 280,000 miles
'14 GLK 350 60000 miles

I have done it in a pinch with no problems noted. They have the same piston diameter and use the same pads.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I'm unable to locate "FSM 42.4-120/3". The secondary chapters are either four or three digits, no single digit or 123.

Of course, I may be missing something.

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83 SD

84 CD

Myy mistake. Its for a w123.

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'85 300D Cal 280,000 miles
'14 GLK 350 60000 miles

Whether or not calipers "match" is a function of piston diameter, not manufacturer, per se.

Tom - seems like I remember an earlier post which said one, Bendix or Ate, accepted a slightly thicker pad which would not fit in the other. Do not remember anything about piston diameters.

I totally agree. is there any way to know for sure what the piston diameter is? I mean I doubt anyone is pulling the piston and measuring it... keeping the brands the same on each "axle" is the best we can do... no?

__________________
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!