Re: Installing Rotor to Hub?

[Darrel <darrelK@domain.elided>]

"John A. Landry" wrote:

> I'm wondering if it would be an acceptable practice to simply swap hubs but
> keep the same rotor?  I have access to a huge hydraulic press where I work and
> can do the work myself.  But I've never installed a rotor before and was
> wondering if there are any tips or tricks I should be aware of.  For one
> thing, it certainly appears the rotor is held on to the Scout hub by nothing
> more than the pressed in threaded wheel studs.  I have a hard time believe
> pressing in studs is all that hold the rotor to the hub, but I guess this is
> how they did it.  So do I just press out the studs, swap the rotors and press
> the studs back in?  Can I get by with simply doing the swap and not bother
> with having to turn the rotor again?  I'd like to avoid removing any more
> metal from the rotor if I can help it... I think I'm at the minimum thickness
> limit.

The studs hold everything together for assembly, then it's really the lug nuts
that keeps the rotor from separating from the hub.  A hydraulic press isn't
necessary for this job. Just use a large hammer and a center punch to knock out
the studs. The center punch should be smaller in diameter then the studs so you
don't damage the threads.  I did this dozens of times in my father's shop with
success.  It's much faster then the using the press.
When you put it back together you'll have to hit the studs fairly hard to seat
them completely. A heavy hammer makes it easy.  New studs are NOT necessary.

Don't waste your precious rotor material.  Only use the lathe if you have
excessive runout. I install the rotor/hub on the truck and place the magnetic dial
indicator stand on the caliper bracket. Anything less then .003 is great. If you
have around .015 or more you will get some pulsing at the brake pedal.
If you have too much run-out swap to a different hub. This will help you narrow
the problem down to the rotor or hub.

> John H. and I talked about this situation on the telephone, and he recalls
> installing *new* rotors and not having to turn them afterwards.  Is that a
> common and accepted practice?

All but the best shops just slap everything together and collect their $60 a hour
fee. You're lucky if they take the vehicle for a test drive before you get it
back.

Darrel Kline
Colorado Springs