<E28> 1987 Wheels and Tire replacement

[Persi Kanga <pkanga@xxxxxxxxxxx>]

Hello all:

Two days ago, I installed 4 new wheels/tires (from DiscountTireDirect.com).
We've established that all 4 wheels are in perfect balance, however, I still
get a very slight shimmy from the steering wheel between 55 and 62 MPH.  I've
moved from the standard 390 rims/tires (mainly because the replacement tires
are $250 each!!) to a 17x7.5 5-120 20B rim and 225/45R-17 Nitto NT 450 Extreme
tires.  There was no shimmy with the Michelin TRX tires (and they were starting
to wear thin).  One note: I was only shipped 3 of the 4 centering rings (the
other one is coming) - I've installed two on the front wheels.

My questions are:  Could one of the front tires be defective, could the absence
of the centering rings on the back hubs cause issues with the front/steering,
does it take a few days for the tires to settle out, or am I being too fussy?
Of course, DiscountTireDirect.com is very helpful...but they don't really have
the answer....they said that they would take care of it if it lasted a few more
days without settling out.

Any added information / experiences would be appreciated.

Cheers, Persi
1987 535is
(with a slight shimmy between 55 and 62!!)

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