Saturday, November 16, 2013

Evo III Caliper Rebuild / VR4 Galant - 42mm Piston Diam - MB699456 vs MB857840

Caliper Casting Numbers - #4304

Banjo Bolt Fitting
Piston Diameter - 42.76mm
Dust boot seal groove - 30.2mm
ID of Piston - 25.5mm

DiY -

MB699456 (42mm piston) vs MB857840 (>42mm piston {yet to confirm size})
 - Note that both dust boots and orings are different sizes
 - orings are larger for the MB857840 (~26mm)
 - dust boot ID is larger for the MB699456 (~30mm)

So one would extrapolate that the piston to pad contact is smaller with the EIII, yet uses a larger diameter piston. I measured the VR4 caliper piston to pad contact @ ~32.1mm

LEFT is the VR4 MB699456
RIGHT is the EIII MB857840

You can see the oring doesn't fit the piston
But the dust boot ID is smaller.

Attacked the caliper with a drill and wirebrush attachment.

Lube the bores with the supplied silicone grease AND/OR brake fluid. I soaked the orings and boots.

I coated the piston with silicone grease and wiped for bores with brake fluid. Seems like it might be similar/easier just wiping the bores and oring with silicone grease.

<- quick coat of VHT exhaust manifold hitemp ceramic paint

I was quoted that the MB699456 was for the VR4
And that the MB857840 is for the E3.

New Rotors to match 294mm >>>>
New Pads to pick ????

It looks like my caliper were in fact a VR4 Galant version, I believe this so as I used O-rings for the 42mm pistons.
The other O rings i had remaining were much larger from the MB857840 kit.
However the dust boot seal ID for the MB857840 is ~26.5mm vs the MB699456 ~30.04mm

You can use the provided silicone grease to lube the pistons and boots and orings OR/AND some clean brake fluid.


MB857840 Fits:
1991-1999 Mitsubishi 3000GT Non Turbo FWD
1991-1996 Dodge Stealth Non Turbo FWD

Repair parts of space for gear that you prepared in the overhaul of this time.
■ F brake Shim Set: MR389653
■ brake seal kit: MB857840
■ F brake clip set: MR389601
■ brake pad: mr389547


  1. This comment has been removed by the author.

  2. thanks for this information.
    just to confirm, did you need to use anything from the MB857840 seal kit?
    or everything you used was from the MB699456 kit.
    thanks again!

    1. i used the #456. which had ~42mm piston orings, but larger dust boot ID

      the #840 kit has larger orings for the larger piston? but smaller dust boot ID

  3. great!
    thanks for replying.
    a lot of valuable information on your blogs.