SEAT LEON MK2 - correct set up?

[red line fun]

hi all

 

i've been directed here from SCN (of which i'm a member) to get clarification re: the correct wheel alignment setting for my SEAT Leon MK2 FR TDi 08 plate, completely standard other than the 18" optional SEAT alloys that it's running on.

 

trying to keep this as brief as poss, i'm getting a droning/rumbling noise coming from the wheels. had it in at my local SEAT dealer for a look, they advised all the bearings are okay but rear tyres are unevenly worn due to rear wheels needing realigned (camber out) and it's the uneven wear that's causing the excessive road noise. i know from SCN that this is quite a common 'feature' of the MK2 Leon

 

so they've advised wheel alignment and new rears, however the rears are currently like this tread depth wise ...

 

 

N/S rear: 4.5 outer, 5.5 middle, 3.5 inner

O/S rear: 4.5 outer, 5.5 middle, 3.0 inner

 

 

... so i'm hoping i can just do the wheel alignment now and keep the rears for a while more.

 

i've previously used star performance in fife (where i'm based) for a wheel alignment and i'll probably use them again as i know they've got a good name. however i've been advised to pop on to WIM and request the correct camber & toe settings for my car to avoid further uneven tyre wear. the last time it was done (about 18 months ago) the 'after' settings were as follows:

 

 

left front

camber: -0o36'

caster: 7o17'

toe: 0o05'

 

right front

camber: -0o47'

caster: 6o58' (this remained 'red' on the print-out, advised this was best they could do)

toe: 0o05'

 

FRONT

total toe: 0o10'

steer ahead: 0o00'

 

left rear

camber: -1o42'

toe: 0o04'

 

right rear

camber: -1o45'

toe: 0o04'

 

REAR

total toe: 0o08'

thrust angle: 0o00'

 

 

i've put the rear camber settings in bold as these are the ones that cause the issue? any advice on what the settings should be for all wheels would be welcome, i hope to get the car done asap.

 

cheers

 

RLF

[Tony]

Hello and welcome to wim

 

The patten of wear is known as "heel and toe" which forms a wave like up/ down variant in the tread depth. H&T wear is a wear frequency that favours a certain size of tread block. If you look at any tyre you will see the tread blocks vary in size in an inconsistent fashion, this is a design feature to reduce the harmonics.

 

H&T is not caused by camber, it's affected by toe! Dynamic toe when incorrect has a lateral scrub effect adding to the pinch during the tyres contact moment. Incorrect toe position during the contact moment twists the favoured tread block demanding a lateral contact but the tread block cannot obey, thus submitting a sacrificial leading edge.

 

That all said it's a simple case of moving the toe position to around + 10' each side depending on the extent of the H&T wear. Point to note is the geometry data offered by Seat is a "suggestion" not the law. Add 18" wheels in to your mix then the OEM data is immediately redundant if you see my point.

[red line fun]

Hello and welcome to wim

 

The patten of wear is known as "heel and toe" which forms a wave like up/ down variant in the tread depth. H&T wear is a wear frequency that favours a certain size of tread block. If you look at any tyre you will see the tread blocks vary in size in an inconsistent fashion, this is a design feature to reduce the harmonics.

 

H&T is not caused by camber, it's affected by toe! Dynamic toe when incorrect has a lateral scrub effect adding to the pinch during the tyres contact moment. Incorrect toe position during the contact moment twists the favoured tread block demanding a lateral contact but the tread block cannot obey, thus submitting a sacrificial leading edge.

 

That all said it's a simple case of moving the toe position to around + 10' each side depending on the extent of the H&T wear. Point to note is the geometry data offered by Seat is a "suggestion" not the law. Add 18" wheels in to your mix then the OEM data is immediately redundant if you see my point.

 

tony

 

many thanks for welcome and detailed reply/advice. now, i'm being VERY careful what i say as i don't want to be banned from WIM after my first post, just trying to get this clear in my brain so i know what i'm saying to star when i get the car done! are you saying the seat dealer is 'misinformed' when they advise it's the camber settings that require adjustment i.e. based on the oscillating droning/rumbling i'm hearing and the wear pattern i detailed earlier is this fully a toe issue and not camber at all? reason i ask that is i'll just leave star to set camber as they normally would (which before was -1o42' left rear and -1o45' right rear.)

 

secondly and to clarify, am i simply asking star to do a full wheel alignment but ensuring they set the rears to 0o10' toe each side? i.e do all their other settings look fine to you?

 

and finally, in your opinion (and bearing in mind i'm skint!) can i leave the current rears on if the toe is fixed i.e. will the tyre wear more evenly from hereon in? or do they need to go i.e get replaced?

 

cheers

[Tony]

No one gets banned in wim for asking questions.....

 

I'm not concerned with the camber position at all and it's not the reason for your complaint. Star are uneducated as to the reason you have H&T wear, yes there is an issue with the camber but camber wear is totally different.

 

You may as well leave the tyres on and they may recover once the toe is corrected depending on how badly they have worn.

[Rich]

Couldn't the tyres be swapped over if needed?

 

Welcome to WIM as well

[red line fun]

thanks again. the car's going in this saturday, based on the tread depths i detailed earlier, should i ask star to set the toe on each rear to +10' or less? if i don't mention anything (and based on the last alignment star did) they'll set toe to around 0o04' on the rears.

[Tony]

Yes tell them to set the toe to + 10' each side if they are measuring 60/1 degree or + 17' each side if they are measuring 100/1 degree.

[red line fun]

great cheers