Jim,
I have had the same phenomenon for as long as I drive the car. In my case it
has nothing to do with changing camber of the wheels or "loose" hubs since I
rebuild the front and rear suspension over the years without the braking
behaviour changing at all. In my case I am quite certain it is the rear brake
pads that relocate while braking when backing up. Apparently the relocation
causes the piston to be located in a different "rest"position after the
braking. This may have to do with the radius of the pads (I already changed
them to no avail, the new ones having the same radius) being different from
the inner drum radius.
Pim
Pimento '73
Date: Mon, 8 Apr 2002 14:07:04 -0700 (PDT)
From: tr6taylor@webtv.net (Sally or Dick Taylor)
Subject: Re: Weird brake question # 163
Jim---It still sounds like the wheels may be tilting when the car
direction is in reverse. (A peculiarity of the castor angle, I think)
You can check this by noting the camber angle of the front wheels after
driving forward, then stopping. Presumably the wheels will be near
'straight up'. Next, drive the car backwards about 20 feet or so. Stop,
to check the camber angle again. If it is now in a negative camber, the
brake pads have been knocked back, as noted by Nelson. The easiest way
of reducing this brake pedal drop is to keep the front wheel bearings
snug. Most TR wheels I've come across were very easy to shake, top to
bottom, as a result of loose bearings. (If you slalom your car, you may
notice how many times the tech inspectors harp on the owners about such
things.)
On the play in your rack & pinion mounts, it sounds as if the mounts
weren't in a slack-free position before the U-bolts were secured. Bob
Lang has a good method for setting these. Perhaps he'll repeat it here.
Dick
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