Outer tyre wear a year on from tracking

[bmouthboyo]

I paid £90 just over a year ago and after only doing maybe 3000 miles on my 215 74 R15 AT tyres I have outer wear on both.

NS


OS


These were the adjustments done to the van:



I did give him the technical specs from the wiki when adjusting but he mentioned something about one of the adjustments being too far to achieve, I forget which.

Do I have a case to have them adjusted again due to the wear? Which setting looks to be off and causing it?

I imagine due to the wide tyres I have it is difficult to fully get spot on, is it possible to stop this outer wear continuing?

Cheers

[937carrera]

You don't say if the wear is front or rear.

Looking at the alignment page, front castor is too high at 9 degrees should be around 7, though that will affect self centring more than wear.

If those settings are accurate, then i would be looking for wear in suspension /steering components. The outer edges look feathered which is indicative of excesive toe in or positive camber

I doubt the tyre size makes any serious difference at this scale

[bmouthboyo]

Sorry front tyres.

All the bushes other than the wishbone were replaced with power flex before adjustment, steering rack bushes, droplink, radius rod, ARB . What suspension component could contribute to this?

[937carrera]

I suspected it would be front.

That does look like tracking to me. I do a fair bit of suspension setup but don't know my way around the details of T25 suspension so well, but essentially it could be any component that has play in it. Starting point would be track rod ends & ball joints. Radius rods also seem to pop up on a regular basis. The issue is that there is more movement on one or both of the wheels which allows the toe in to increase when the van is moving forward. Wheel off the ground and see if you can detect any excessive play, a pry bar may well be necessary. If one side is out, you will have adjusted the steering wheel position to keep the van going straight so both sides wear.

Others might have more relevant specific experience.

[bigherb]

That looks like cornering wear. What is the offset (ET) of the wheels?

[bmouthboyo]

That looks like cornering wear. What is the offset (ET) of the wheels?

They are ET37 but I had slight fouling so had to add 10mm spacers each side. If it was cornering any way I can mitigate this?

Thanks for help so far everyone.

[937carrera]

Might as well give the wheel width as well

[bmouthboyo]

Sorry I thought that was calculated from the tyre height and percentage. I think the rims are 7J, so I assume 7 inches?

[937carrera]

Yep, 7J means 7" rims the calculation you refer to is to calculate sidewall height from width and profile.

The spacers have reduced ET from 37mm to an effective 27mm, as you say to eliminate fouling due to the wider rims.

I've seen references saying ET should be between 30 and 39, so on the face of it you are only 3mm out, but I'll leave Bigherb to give a more informed view on the potential effect of that for your van.

[bigherb]

That looks like cornering wear. What is the offset (ET) of the wheels?

They are ET37 but I had slight fouling so had to add 10mm spacers each side. If it was cornering any way I can mitigate this?

Thanks for help so far everyone.

That's' possibly the problem. The offset is designed to have the centre of the tyre contact on the road pivot on an imaginary line the steering pivots on the road. Moving the offset particularly outwards causes the tyre to move in an arc around the pivot point causing the tyre to scrub the more the steering is turned. You have to recalculate the offset when fitting wider wheels.

[bmouthboyo]

That looks like cornering wear. What is the offset (ET) of the wheels?

They are ET37 but I had slight fouling so had to add 10mm spacers each side. If it was cornering any way I can mitigate this?

Thanks for help so far everyone.

That's' possibly the problem. The offset is designed to have the centre of the tyre contact on the road pivot on an imaginary line the steering pivots on the road. Moving the offset particularly outwards causes the tyre to move in an arc around the pivot point causing the tyre to scrub the more the steering is turned. You have to recalculate the offset when fitting wider wheels.

Is this something I could pass the details onto an alignment workshop for or is there an online calculator or tool?

[937carrera]

There will be a number of online tools, just do a quick search if you want, but here's how I calculate it

Std wheels are ET 39. You have fitted 7" wheels which are ~38mm wider, or 19mm either side of the mounting face with an ET of 37.

On top of that a 10mm spacer has been fitted so the inside edge of the wheel is 2 + 19 - 10mm further in = 11mm

The outer edge is 19 -2 +10 mm further out = 27mm

11mm +27mm = 38mm = the increase in wheel width

I don't have a great deal of faith in generic 4 wheel align workshops. At the risk of being unkind, they know how to use the machine and work to what the setup computer says, but generally little else about suspension.

Have a read here too

https://www.brickwerks.co.uk/wheel-fitting/

http://t3technique.com/media/pdf/Vanago ... _Facts.pdf

[bmouthboyo]

There will be a number of online tools, just do a quick search if you want, but here's how I calculate it

Std wheels are ET 39. You have fitted 7" wheels which are ~38mm wider, or 19mm either side of the mounting face with an ET of 37.

On top of that a 10mm spacer has been fitted so the inside edge of the wheel is 2 + 19 - 10mm further in = 11mm

The outer edge is 19 -2 +10 mm further out = 27mm

11mm +27mm = 38mm = the increase in wheel width

I don't have a great deal of faith in generic 4 wheel align workshops. At the risk of being unkind, they know how to use the machine and work to what the setup computer says, but generally little else about suspension.

Have a read here too

https://www.brickwerks.co.uk/wheel-fitting/

http://t3technique.com/media/pdf/Vanago ... _Facts.pdf

That is super helpful 937carrera thank you.

What I am now a bit unsure of is how I use this knowledge to have my tracking adjusted to correct it. IS there a way to take this and be able to calculate the camber, toe etc angle I would need with these tyres? Or is it a case of my tyre is simply not suited to the vehicle and no adjustment will get it to wear evenly?

[937carrera]

Your tracking doesn't adjust it....... tracking is only one of many components making up wheel alignment. One of the reasons why I generally don't mess about with changing rim sizing. Looks good handles crap and don't get me started on "stretch".

Could you get away with thinner spacers - just to reduce the potential effect ?

Don't forget to check the basics I posted earlier, track rod ends and ball joints. Could still be that.

[bmouthboyo]

Your tracking doesn't adjust it....... tracking is only one of many components making up wheel alignment. One of the reasons why I generally don't mess about with changing rim sizing. Looks good handles crap and don't get me started on "stretch".

Could you get away with thinner spacers - just to reduce the potential effect ?

Don't forget to check the basics I posted earlier, track rod ends and ball joints. Could still be that.

I originally went with these as the larger diameter would bring my RPM down in my GTI conversion. https://club8090.co.uk/forum/viewtopic.php?f=41&t=160780

I tried 6mm spacers but still had some slight contact and the next size I found was 10mm from BW. They are just basic 2104000702 steels but would be a shame to have to get more wheels. Could the brake carrier be ground back a few mm where it contacts the steel with smaller spacers or is that a big no no?