[DeTomaso] Steering rack adventures

[Charles McCall]

Hi all,

Ever since I bought my GT5-S, it has tramlined fairly badly. The car has
been a handful to drive, particularly on bad roads. Under hard braking, the
car would dart from side to side - not pull to one particular side, but
would go left-right-left-right requiring constant correction.

Last year I installed offset bushings up front, which improved the situation
greatly, although not completely.

At Le Mans this year, Mike Drew pointed out that I had all kinds of play in
the steering system. The car has more or less always been like that, so I
had not particularly noticed. But he was right - there was all kinds of
play.

Taking advantage of a visit by Tomas Gunnarsson this week, we just came in
from looking at what was happening. Basically, one tire (passenger side) was
nice and tight, but on the driver's side, turning the wheel resulted in
up-and-down movement of the tie rod instead of side-to-side. There was lots
of play on this side tire, which allowed all kinds of weird toe in/toe out
settings, depending on the position of the wheel. Tomas was hoping that it
was just a adjustment issue - there are a series of shims that basically
adjust between binding the steering rack and allowing free play between the
rack and column.

Off came the cover and we found 4 shims inside - one thick and three of
various (thinner) thicknnesses. We reinstalled the cover with NO shims and
found that the steering rack now was binding, but there was zero play. A-ha!
To make a long story short, we experimented, adding shims until we got no
binding, then removing them until it bound, and adding one more to get
minimum clearance. My steering rack is now completely tight, with no play
whatsoever, perhaps for the first time in the history of the car!

What I found amazing was that this steering rack was assembled this way.
Tomas has two possible explanations - during assembly there was some dirt of
something in the assembly which meant that the rack was ok when bench
tested, but when installed and driven this dirt broke down and opened up all
kinds of clearance, allowing lots of play. Or, the rack was just badly
assembled from day one, installed, and nobody ever looked into it.

Note that early steering racks and late steering racks are apparently quite
different, but those of you with late model cars, if you have play in your
steering wheel the fix could be free and could be done in a couple of hours.


Anyway I'm a happy camper as I had been mentally preparing myself for buying
a new steering rack... we just came back from a short test drive and it
feels like a new car. The darting under heavy braking is gone, and the
steering is now rather direct, as it should be.

Your mileage may vary...