Diagnose my suspension fault.

Page 1 / 3
fordcrzy, May 10, 10:30am
ok so wifeys 2002 ipsum is chewing out the very outer shoulder of the left front tyre. im talking the VERY outside edge of the tread block. it did it to the old set of tyres, and when i put a new set on i had an alignment done. The new tyre is doing the same thing. no obvious looseness n the suspension when rocked.the wear pattern is almost like the tyre is rolling over when turning.
the RHS tyre is wearing normally
the only thing i can think of is a failing lower arm inner bush but it seems ok.ill post a pic tomorrow.

jmma, May 10, 10:33am
Hitting the kerb!

fordcrzy, May 10, 10:36am
haha no shes a good driver.its like the left has EXTREME toe in or about 3 degrees of POSITIVE camber on it.weird wear pattern.alignment showed nothing majorly out of spec.
the same wear pattern over about 45,ooo kays, 4 or 5 wofs havent picked up anything and 2 wheel alignments.

edangus, May 10, 10:38am
Rim poked! - Wrong!

usdefault, May 10, 10:38am
Fat wife!

unbeatabull, May 10, 10:40am
How did the Caster alignment look like!

Is it front or rear, or one side more then other!

fordcrzy, May 10, 10:41am
haha no shes a bean pole.

fordcrzy, May 10, 10:42am
front left tyre only. all others wear normally. car tracks straight.
lack of castor on that corner was one thing i thought, but ive lost the alignment sheet.

kingfisher21, May 10, 10:44am
Driving habits and tyre pressure, left hand front outer is the tyre that always gets the severe wear especially on a round town runabout, camber and castor, castor BTW won't cause tyre wear, are non adjustable.

unbeatabull, May 10, 10:44am
Hmm, past experience says otherwise

jmma, May 10, 10:46am
Yes, maybe turns around in lots of dead end streets.

kingfisher21, May 10, 10:47am
You tell me then how castor can directly affect tyre wear!

fordcrzy, May 10, 10:49am
castor acts like camber when the wheel is turned. the camber and castor give a combined angle to the road when turning the wheel. camber is left/right angle and castor is front /back angle so the more you turn the wheel the more castor contributes to the combined angle to the road.
i though lack of castor was causing the outer edge to "trip" on the road when turning sharpley!

kingfisher21, May 10, 10:51am
Wrong, what you are refering to is SCRUB RADIUS. It gets complicated, SAI and Scrub Radius can cause all sorts of problems, need to see your printout.

fordcrzy, May 10, 10:57am
no scrub radius is the point where the angle of the suspension movement intersects with the vertical plane of the tyre. that point should be on the ground at the central vertical plane (Of the tyre) thats why fitting wider offset wheels screws the scrub radius

fordcrzy, May 10, 10:59am
if camber was 1 degree and castor was 5 degrees.

when going straight the angle to the road would be 1 degree.
if you turned the wheel left or right 90 degrees it would be at 5 degrees to the road.see what i mean! lack of castor when turning is like lack of camber when leaning. i think its called combined camber gain or something similar!

kingfisher21, May 10, 11:03am
No it wouldn't, think about it.

http://www.familycar.com/alignment.htm

fordcrzy, May 10, 11:11am
your missing the concept totally.
re read post 16 again and think about it.
camber is the lean in and out.castor is the lean front to back.

the more you turn the tyre away from straight ahead position, the more the castor angle comes in to play.

fordcrzy, May 10, 11:14am

scuba, May 10, 11:33am
so your basing your answer on some dicks idea on how to set up radio controlled model cars.good one . how old are you and why are you up this late .go to bed.

scuba, May 10, 11:34am
sorry lol couldn't resist

scuba, May 10, 11:36am
post the wheel alignment readouts and you may get a result.

ceebee2, May 10, 11:53am
I know some brands of tyres are prone to this although not just on one side.sounds like geometry is definitely incorrect irrespective of the last wheel alignment. Could have been operator error in set up.

snoopy221, May 10, 12:01pm
I won't be swayed in to ANY suspension w/align caster camber scrub radius etc baloney-WITHOUT A PRINT-OUT
(And that may be only as good as the operator-having seen people fired and leaving magnets on machines-road test-place vehicle on ANOTHER machine and well)

However as to your SPECIFIC wearing of a left shoulder on a left front tyre.

Way back **Dunlop Le Mans ** tyres were sold in New Zealand and had EXACTLY the same problem.

The N Z V AustraliaFormula Ford championship-where they HAD to run those tyres showed australia had the

SPECIFIC wearing of a right shoulder on a right front tyre.

vr4_legnum, May 10, 1:15pm
Best thing will be to book it in for a wheel alignment and get them to check out the camber as you must find it might need a camber bolt. i think you can do camber on them. you should be running at least 36-38psi in each tyre aswell