Arvin Meritor Casting numbers
The identification of the calipers sometimes really hard because the Genuine datasheet often gets damaged during the excessive use of the caliper.

But there are other options to identify the caliper without datasheet. If the caliper casting numbers (see on the photos) are readable there should be no problem with the identification process.

You will find one number on the "head" of the caliper : 

The other casting number you can find near the "tappets" :

The last one is on the "back" of the caliper :