MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG ZR ZS ZT Technical - Mismatched tyres

My wife has just taken delivery of a 1yr old ZR 120. Only one problem: on close inspection when we got it home I noticed that the front tyres are not matched: Dunlop SP Sport 9000 on one side (and rear) and a Dunlop SP Sport 01 on the passenger side. They have very different tread patterns (Dunlop describe the former as "ultra high performance" and the latter as only "very high".

I'm looking for opinions on safety: my view (as an F owner) is that they must be the same which will require 2 matching new tyres for the front. We will attempt to get the dealer to cough up.

The car does tend to pull one way when accelerating, so I am sure it does affect safety.

Thanks for any comments,

Graham.
Graham Berridge

Graham - Don't worry, it will have no detrimental effect whatsoever.

Now, if they were tyres from different manufacturers, then I'd be concerned.

The pulling to one side (Which side, incidentally?) is pretty normal with big wide tyres and crap UK roads...
Eric

from Dunlop's own website -
http://www.driveradviser.com/tyre/the_law.shtml

it's only illegal to mix crossplay and radial tyres in certain situations, otherwise you can mix tyres as you like, as long as they are the correct tyre size designed for your car.

the performance rating given by Dunlop inlcudes speeds above our current legal limit anyhow.

Is your tyre here?
http://www.dunloptyres.co.uk/site/tyres/car/patternSearch/

pulling to one side does need checking. You can check the tyres pressures yourself at any petrol station, my Sainsburys has a digital one. Any tyre garage will check the alignment, usually free of charge, and they will confirm the situation about your tyres if you would like a second opinion.

The dealer should check the power steering after that.

British roads are engineered with a camber to the left, to allow rain water to drain away.
Gary

check your sidewall markings for the letter "R", where R = Radial

http://www.dunloptyres.co.uk/site/tyres/car/sidewallMarkings/
Gary

Graham, you state that the fronts are mis matched, but what about the rears? What are they?
I'd consider putting the rears on the front and vice versa. As the ZR is FWD, the fronts do most of the work (power delivery, steering, majority of the braking etc).
Whilst it may be legal, and 'in theory' not affect the handling, If it was me I'd feel happier with the same on both sides at the front. The rears are just along for the ride.
JLD

About to post a similar reponse to JLD's spoy on one ..... With most cars, particularly Front wheel drive ones, the best tyres should always be on the FRONT. As JLD rightly points out, the rears play little part as 80%+ of the braking, steering and acceleration is done by the front wheels....

John
John McFeely

Thanks for the pointers - I was planning on swapping the rears to fronts to see if that helps anyway, but wanted some definite advice!

The car has a space-saver spare, so I guess the previous 9000 got punctured and replaced in a hurry/cheaply. On the F I would ensure both tyres on an axle got changed at the same time. The size/performance/rating codes on the tyres are the same. We'll go and argue for a replacement pair. Its got Dunlop SP 9000s on the rear.

Any preferences for replacements? Are the 9000 worth staying with?

If anyone's still reading - is it normal to hear the engine belts (water & power steering ?) in the car when idling? There is a noticeable low-pitched drone which (from under the bonnet) seems to come from there. I was wondering if one was too tight?

Graham.
Graham Berridge

This thread was discussed between 02/10/2004 and 04/10/2004

MG ZR ZS ZT Technical index

This thread is from the archives. Join the live MG ZR ZS ZT Technical BBS now