Unusual Tyre Wear - Rear Right

[TenaciousC]

Hi All,

Anyone care to suggest why I might be getting inner and outer shoulder wear on one tyre only (rear right) ? It's an estate with Nivomats. Pressure is 33 PSI. It's been 4 wheel laser tracked last year in October. I can't sense any handling issues all seems as normal.

Thanks for any ideas.

C

[jamesy12345]

Shoulder wear usually means under inflation, but 33 psi sounds OK for an unloaded car. For heavy loads or hard cornering maybe try upping the pressure a little.

http://www.carbibles.com/tyre_bible_pg3.html

[TenaciousC]

Shoulder wear usually means under inflation, but 33 psi sounds OK for an unloaded car. For heavy loads or hard cornering maybe try upping the pressure a little.

http://www.carbibles.com/tyre_bible_pg3.html

Yes, it looks like classic under inflation... though the pressure says otherwise.

I've just done a crude test of the track, by putting a straight 5ft pole against the tyre and measuring the distance from the sill and the end of the pole. On the worn side it's about 3/4 inch and on the OK side it's 1.5 inch. Looks like they're not quite pointing in the same direction (assuming the sills are not bent)!

Assuming the left wheel is aligned correctly... a bit of trigonometry tells me the right one is 0.62 degrees different and the range is supposed to be -0.11 to 0.25 degrees.

Is the toe adjustable on the rear suspension?

C

[jamesy12345]

Yes, it looks like classic under inflation... though the pressure says otherwise.

I've just done a crude test of the track, by putting a straight 5ft pole against the tyre and measuring the distance from the sill and the end of the pole. On the worn side it's about 3/4 inch and on the OK side it's 1.5 inch. Looks like they're not quite pointing in the same direction (assuming the sills are not bent)!

Is the toe adjustable on the rear suspension?

C

I could be wrong but seems that one side toe out is about 0.7 degrees & the other is 1.4 degrees? that would have shown up in the laser alignment if it was out

angle = sin^-1 (19/1524)



//edit

some values in the link below, and a section on adjusting rear toe

https://www.volvoclub.org.uk/tech/se...Procedures.pdf

[M-R-P]

Get it aligned on a hunter system.
Most alignment places will just align the front wheels to the rears and that's no good for Volvos. They need to be aligned independently.

[Nealevo]

As above, get it done on a good machine, not sure of newer models but my 850, all wheels can be independently aligned.

[M-R-P]

As above, get it done on a good machine, not sure of newer models but my 850, all wheels can be independently aligned.

Even more adjustments on p2 iirc

[Saaamon]

As said really need to have it done on a hunter system and with that you'll get a before and after print out, then you know its actually been done!

[sunny scott]

Excuse my Ignorance here as only new and never knew about the Hunter system, Do Volvo use this for alignment? any Scottish guys on here know who has this system? just in case I need it in the future.

[jamesy12345]

Excuse my Ignorance here as only new and never knew about the Hunter system, Do Volvo use this for alignment? any Scottish guys on here know who has this system? just in case I need it in the future.

Google says..

http://www.pro-grip.org.uk/index.html nr Falkirk

http://www.mtekbmw.com/index.asp?key=9 Rutherglen

[stephenevans99]

Had mine on a Hunter system a few weeks back, a very impressive system and not expensive either....






Mine was done by DP Tyres in Wigan