Tire size difference on Eclipse AWD - how serious?

you need to run tires of the same diameter. running differents sizes will roast your viscous coupling. the car deserves decent tires and buying a new set resolves your mismatch problem. the eclipse is not a difficult or overly complex car yet there seem to be quite a few mechanics who either won't or shouldn't be servicing it. the way your post reads it is two strikes on the mechanics search so far....perhaps put up a post at

Your AWD requries the same make, model and size of tire on each end. Otherwise, you risk frying the viscous coupler in the transmission. This part is C$1400, and generally requires the transmission removed to replace it. Once the VC is fried, the AWD will still work, but without the central locking that gives the performance and handling.

You can check the VC as follows: with the trans in neutral, lift a front off the ground and turn it by hand (or with a lug wrench). If the VC is OK, the wheel will require quite significant effort to turn it. This is because the rear wheels are locked on the ground, the front diff is working, and the center diff is working, but impeded by the VC action.

If you can easily turn the lifted wheel by hand, your VC is fried.

This is not an absolute test, but will give a rough idea of the VC condition.

Stewart DIBBS

Diameter? Or circumference? There is a big difference!

Jon

Jon,

Thanks for catching my error. It was 3/8" circumference difference. By my quick calculation, that's a radius difference of about .059 inch. - a little less than a 1/16 inch.

Isn't that well within the normal wear radius of a tread?

Is a tread thickness difference between the front and rear tires of a 1/16 enough to overwork my viscous coupling?

Thanks to all who have answered my question,

Marc Sterling

in article snipped-for-privacy@4ax.com, Jon Sturgeon at snipped-for-privacy@futuresoft.nospam.com wrote on 9/18/03 3:04 PM:

Marc, You also have to consider the loaded ride height of the different brand tires. Some have stiffer sidewall than others. You wil also be happier with the handeling if you drive in that sporting fashion.

Oh, You really need to find better mechanics. Check out a local sports car club, get to know fellow DSM drivers they'll be more than happy to steer you to a good DSM mech.

Fled.

G3 Eclipse GTS

Marc Sterling wrote in news:BB8F8C15.1947A% snipped-for-privacy@serenescenes.com: