Paul The retaining plate for the ring gear used on 2.85 redrive shows
    8 flat head machine screws to hold it in place do you have any idea what
    size ? I have my housing machined so all will fit and I am ready to
    drill and tap housing to hold retaining plate Thanks Keith

    No I don't but my guess is 1/4 28 would do.
    What is the bolt circle diameter?
    I have the dwg but I'll have to load it into Rhino
    and scale it. Looks like there is room for 5/16th.

    Paul Lamar

 -Paul   the largest diameter bolt circle useing 3/16 flat head will
    just clear the ring gear and at that diameter I can put nuts on
    outside of the housing  if I go to larger flat head then bolt circle
    diameter will be required
    thanks Keith-

In theory a 3/16 bolt should hold a shear load of 4000 pounds
assuming a 150,000 psi bolt.
Times eight is 32,000 pounds. If the bolt circle diameter is
about 3.5 inches that is a torque of  112,000 inch pounds
or 9000 foot pounds. That should do it.

Paul Lamar