Readings from an alignment job

[quadcam Junior Member Find all posts View Profile Close quadcam]

Mansour: I have Yokohama Geolandar HT-S 265/65x17 tyres which have significantly more tread depth and two largish rain grooves. They seem like a good road tyre with an ok looking profile for sand but with a bit more bite should it be needed on other surfaces. I can't comment further than that, as of all the 4wd's I've had this one hasn't been further than a gravel road.

Jacto, the front bottom arms have camber adjusting bolts in them. Maybe you could do caster with different bottom washers but I haven't had a good look.

Fazza, thanks for the explanation, I'm no suspension expert but like to know how things work (must be a bloke thing, but I haven't mastered the epicycle torsen centre diff diagram yet).

I was under the impression that caster (castor?) has the effect of straightening the wheels when they are turned, don't they measure the caster with a slight turn on the wheels? I didn't know it sort of induced a turn from straight ahead.

I can understand the toe-in causing wear but wouldn't it be accentuated on the side which the wheel is cambered to, ie inner on the left side due to negative camber and maybe neither side on the right tyre due to positive camber but toe in (I don't know which would override the other). The original tyres were completely stuffed on both the insides and outsides of all tyres, but I only rotated them front to back, not like the book as I am doing this time.

Looking at the imaginary line through the ball joints the pivot point seems to be on the inside of the tyre (is that called positive scrub geometry ??). Would this mean that the outside of the tyre is dragged more thus inducing more wear?

Thanks for the informative discussion.

[Justo Advanced Member Find all posts View Profile Close Justo]

The original tyres were completely stuffed on both the insides and outsides of all tyres, but I only rotated them front to back, not like the book as I am doing this time.

G'day quadcam. It sounds like you might be running your tyre pressures a bit low if they're wearing both edges.!
What pressures do you normally run on.?

[quadcam Junior Member Find all posts View Profile Close quadcam]

I ran the original tyres at std pressure, 1.9 bar but am running the current tyres at 2.3bar. I am just about to rotate them at 5k km after fitting so will have a good look.

I have realized i might be confusing myself or some/all of us because we may not be talking the same conventions. I have been assuming that - for camber means the top of the tyre is leaning in towards the body and that + for the toe means the fronts of the tyres are closer together (my gut feeling is that - should mean in for toe but I think that may be wrong). Is this what the printouts mean or are some machines different? I think I have previously seen toe values in both degrees and millimetres just to further confuse things.

[Fazza Senior Member Find all posts View Profile Close Fazza]

quadcam,

As I said & you have picked up on, each of the lower arms have 2 ex-centric bolts, which means you can not only move the arms in & out (camber) but forward & back (Caster)

CASTER. Yes to straightening the wheels when turned, but lets exaggerate things by making one side, lets say right extremely positive & the left extremely negative. What would happen is the high caster would win & make the car steer left. Also the higher the caster the more it will follow a cambered surface e.g. try pushing a shopping trolley on a side slope.

As for toe-in:- Yes it will cause more wear on the side with the highest camber, but only if you have to much. That is why it should be zero. (Very rare to see outside edge wear on the right tyre with left hand drive cars) again due to our cambered roads.

The imaginary line through the ball joints to the centre of the tread is the scrub angle but can only be altered by fitting different offset wheels.

I would suggest your alignment is ok if you are getting even were inside & out, but as Justo mentioned low tyre pressures or living in the city and doing a lot of turning.

Just as a example Find some smooth concrete, pull your car on full lock & accelerate, or if you like do a dough nut. Now get out and see what you have left behind. (Those black marks are from the shoulders of your tyres)

Again drawn out

Sorry, Fazza

[Fazza Senior Member Find all posts View Profile Close Fazza]

Quadcam,

Missed your earlier post
Camber + is leaning out from the body
Toe in is wheels pointing in at the front
Caster Leaning forward or back of wheel (+ or positive leaning back from top) eg shopping trolly wheels

My bed time

Fazza

[Jacto Senior Member Find all posts View Profile Close Jacto]

Thanks Fazza and Quadcam, I haven't been under a vehicle to do a wheel alignment for around 8 years now so it is good to remain informed for when I go to get mine checked.

[Justo Advanced Member Find all posts View Profile Close Justo]

Quadcam, I just had to convert the 2.3bar to something I actually understand.. 8) Thats about 33 PSI, which shouldn't be too bad. I'm not sure what everyone else runs their pressures at, but I run between 38-40 PSI (2.6-2.75 Bar) and dont have any edge wear at that.

[mansour Member Find all posts View Profile Close mansour]

Waoo

Guys

Thanks a million for your expolination , clearly the idiot dealer and his technicians just want to push me a way with the word OK that you see on the print I listed earlier.

I will look into the Geolkander but the reader feedback from the web suggest the Prillie's being more superior than the rest

As a conclusion shall I consider Quadcam's figures when I go for re-alignment and the new tyres ? We do drive opposite side of Austrlia

Again thanks to all the great effort that you put into this :P :P :P

[Fazza Senior Member Find all posts View Profile Close Fazza]

mansour,
As you drive on the right side of the road your camber figures are ok.
I would prefer to see a slight bias with the caster to give a slight drift to the left & help hold the road camber.

Camber Left +30 Right 0
Caster Left +2.50 Right +3.10
Toe - In 0
Checked loaded or at least with the weight of the driver.
That's basically the formula I have been using for many years.

Have fun.


Fazza

[mansour Member Find all posts View Profile Close mansour]

Thanks Fazza

I will do these setting to my Rig ; Thank you Fazza , Thanks mates for your help :lol: :lol:

Darn to all Toyota Dealers around :evil:

[phil Member Find all posts View Profile Close phil]

Fazza these are the figures ATS gave me to adjust mine after lift.
Set camber no more than -0.30 degrees
Set toe to pos 1-2mm
Set caster to pos 0.30 degrees
they have mentioned that caster is critical!!
and watch lhf toe for tyre wear.
What do you think about caster angle and the neg camber on both wheels.
Cheers Phil.

[Fazza Senior Member Find all posts View Profile Close Fazza]

Phil,
Caster does not wear tyres but will make the steering heavier & more stable at high speed (Positive Caster)
or lighter but more flighty (Negative Caster)

Camber & Toe - in are the most critical settings for tyre wear.

I would suggest:-

Camber Left -0.30 Right 0 Degrees
Caster Left +2.00 Right +1.50 Degrees
Toe - in 0
All settings should be checked with weight in vehicle e.g. at least the weight of the driver.

The caster settings could be slightly higher or lower but with approx same variation.

These settings will give a slight bias to the right or hold the road camber.
This is opposite to mansour's as they drive on the other side of the road.
Also the caster is lower than mansour's, the only reason, that is where is settings are already on his vehicle.

I don't understand ATS,s comment on Caster being critical & Left hand toe for wear? (Toe is the total of both sides)
They may have suggested that you watch for left tyre wear?

Hope that answers you questions.

Fazza.

[phil Member Find all posts View Profile Close phil]

Fazza thanks for the reply, these are the exact things ATS sent me by fax,
I am a Mechanic but don't know alot about wheel aglinment, I did think the caster was way out there. My prado did drive ok after lift with no aglinment, so i had someone do it and now car pulls slightly right they couldn't even get the steering wheel straight. It's very hard these days to get someone to do aglinment properly even if you let them know that you will pay double no questions asked for a good job.
Specs now are: camber left -0degrees 23'
right pos0degrees 26'

toe left 0.8mm
right 0.8mm
caster left pos0degrees 51'
rightpos027'

So you can tell why my car pulls to the right slightly. Will have to try again at a different place. Hate the thought of wearing tyres out when they cost $300 plus each when none of my past vehicles have.And those cars were never treated like this one is. Cheers Phil.