how difficult is diy brake pad/rotor RR on 97 E420? (fronts)
 

wondering how difficult the job is, and what tools I need? also, i bought the car with 105k miles and I have 108k now. Should I replace the rotors too?

i'm sticking with OEM parts, but drivewire dot com lists several choices on the pads, PBR, Jurid, Genuine, etc etc? rotors = brembo, balo, zimmerman, ..??? do i also need brake pad sensors and pins?

It's easy
 

as brake jobs go. if you've worked on US cars, the difference is that you need metric sockets, and you have a 5-mm hex screw holding the rotor to the hub.

Use jackstands, torque the caliper mounting bolts on correctly and you can't go very wrong. The only obstacle is a rusted on rotor occasionally requiring Liquid wrench and some coaxing with a puller or hammer, but I've never had that on the fronts - just don't forget your 5mm hex screw before you assume it's rusted on.

thanks! i will do the pads only, so it'll be even easier. but - do i need a c-clamp tool for the new pads?

ProV1, only replace the rotors if they're worn to near the minimum thickness stamped on the OD. Yes, you'll need new wear sensors; but reuse the existing pins. I recommend Textar brake pads if buying them online, or use original braked pads from the dealer. You can use a C-clamp or pliers to push the pistons into the calipers so you have sufficent space to install the new brake pads.

The piston can be squeezed back in with a slip joint, aka "water pump" pliers, a fairly large pair.
No need to replace the sensors if the pad warning light isn't on AND you can remove it w/o busting it.
The rotors can be reused IF they aren't worn below the SERVICE spec, not the min spec stamped into the disc. For reference the service spec is normally about .3mm thicker than the min. spec., you should be able to find a source for the service spec somewhere online. The service spec is the spec at which you should still be able to get through another set of pads w/o dropping under the min spec on the rotors. Also for reference, most of the time with a new rotor you can replace the pads once w/o having to replace the discs, in other words you can go through 2 sets of pads on a new pair of discs.
Gilly