Shakes and inner tire wear

Hi all,

My 98 Lumina gets the shakes above 60 mph (the worst coming between
60-65 mph). I have noticed the inner front tires have worn out badly,
especially on the drivers side. Could this be one problem that is
causing both conditions or a combination of problems? Based on past
experiences, I am reluctant to have the local shop do a trial and
error on it until they find the problem. Any help would be greatly
appreciated.

Thanks
Smerby

In rec.autos.misc,
Smerby > wrote:
> Hi all,
>
> My 98 Lumina gets the shakes above 60 mph (the worst coming between
> 60-65 mph). I have noticed the inner front tires have worn out badly,
> especially on the drivers side. Could this be one problem that is
> causing both conditions or a combination of problems?

I'd say combination. The shakes at 60 (and probably cutting out around
80-90 mph or so, if you get it up there?) sound like a wheel balance
problem. You can get a rough idea of whether it's the front or back
tires having the most effect by discerning whether the shake is through
the steering wheel or the seat.

It could be other things -- problems with the tires themselves, damaged
rim, loose tie rod ends -- but there's no point in investigating any of
that until you're sure everything's balanced. You want to go somewhere
that does road force balancing; the Hunter GSP 9700 is the balancing
machine of choice, but every place won't have one. If you're looking for
a new shop, the presence of one might be a good start for this problem.

http://www.craigautometrics.com/huntergsp9700.htm

Uneven tire wear usually means that end is out of alignment. Does the
car pull, too? Are the tires always run with preroper inflation?

Be sure to rotate regularly (I aim for every 10,000 km, I don't know
the imperial rule of thumb), but note that not rotating wouldn't cause
the problems you're seeing (but rotating would've probably led you to
detect the wear issue before now, so... :-)

I suspect that even if there is a deeper problem at hand that any shop
you go to will want to balance (for the vibration) and align (for the
uneven wear) first, if only because it would be difficult to diagnose
a deeper problem without knowing that the wheels are balanced and
aligned.

-Rich

--
Rich Lafferty --------------+-----------------------------------------------
Ottawa, Ontario, Canada | Help save the endangered Mountain Walrus!
http://www.lafferty.ca/ | http://www.end.com/~jynx/walrus/
----+-----------------------------------------------