Technical Uneven front tyre wear

[smart51]

I've noticed that my front tyres are worn round the outside but are like new on the inside. I'd normally put that down to enthusiastic roundabout technique, but both sides are the same. Is this normal for a 500 or is the camber a bit too much?

 

[bugsymike]

@ Puggit Auld Jock is the tyre man, but to me it does look like a Camber issue, as no signs of the tread "feathering" which you often see when excessive toe in of wheel alignment with that amount of wear difference side to side.
Just a thought, does the car when on level ground appear to sit lower at the rear as I have seen cars where rear springs weak or when a vehicle constantly carries a heavy load that it alters the front wheel/suspension geometry.
Apart from that I have found some makes of tyre scrub off tread much earlier than other makes with hard/spirited cornering.

 

[fiat500]

I've noticed that my front tyres are worn round the outside but are like new on the inside. I'd normally put that down to enthusiastic roundabout technique, bu both sides are the same. Is this normal for a 500 or is the camber a bit too much?

View attachment 444108

You're meant to check that there is zero or minimal toe-in with the vehicle weighed down as if with a full load of passengers...I used a front trunk filled with concrete blocks. But as most of us probably do most of our driving, alone in the car, I wonder if the toe should be set with minimal additional weight (13st for instance? )?

Those don't look like Pirellis; I have found that unfortunately, cheaper makes of tyre don't perform or wear as evenly as the original-style Cinturatos.

 

[smart51]

I seem to have 0.25° of camber with three 25kg bags of sand on the driver's seat, though this tool always gives variable results. If you were to ask me what tyre wear would be caused by insufficient camber, I wouldn't have picked this.

 

[bugsymike]

I used to use a Dunlop Caster and Camber gauge which you held against the wheel rim with a fair degree of success.
By the way have you tested the road surface for level also?
It does appear to be positive Camber which is causing the tyre wear though as suspected.
Back to what I said earlier re weak rear springs etc. If you stand back does the car appear lower at the back and if so can someone on Forum give correct height measurements to compare with yours.
As a very rough test, is it possible to run both the back wheels up on a thick plank of wood to level it up and then measure the Camber again, if that doesn't affect your readings then it would indicate to me that the issue is more at the front suspension.

 

[smart51]

I zeroed the gauge using a set square placed on the floor next to the tyre to null out any slope on my garage floor. I can check the rear later on.

 

[Goldnrust]

A small amount of positive camber like that I wouldn't have thought would be enough to cause that drastic a tyre wear, or certainly not without many thousands of miles of driving.

My money would be on a tracking issue. My tracking was out by a fair amount on my old Daimler a couple of years back and it worn the front tyres in a similar manner.

 

[bugsymike]

A small amount of positive camber like that I wouldn't have thought would be enough to cause that drastic a tyre wear, or certainly not without many thousands of miles of driving.

My money would be on a tracking issue. My tracking was out by a fair amount on my old Daimler a couple of years back and it worn the front tyres in a similar manner.

I accept tracking often accounts for wear on the tyre's edge, however if you look at the tyre in the photo there is no sign of "feathering" which usually accompanies excessive "toe in" in cases like that. Another sign of excessive "toe in" can be really noticable "self centreing" of the steering wheel after turning a corner, something positive Camber is not so likely to affect.
On customers cars in the past I could detect it by simply running my hand across the tread, in very simple terms it was like running your hand across a saws teeth, easier one way than the other. This was then confirmed when I checked with my tracking gauge prior to adjusting to makers specs.

 

[smart51]

Garage floor to the bottom of the cill is 120mm at the front and 135mm at the rear. I took it on a short run to the levelest place I know, the dam wall at a nearby reservoir. Here's a pic. Road to cill is 1 phone and 2 fingers at the rear, 1 phone and 1.5 fingers at the front.

Jacking up the rear had no effect on front camber.

 

[bugsymike]

Garage floor to the bottom of the cill is 120mm at the front and 135mm at the rear. I took it on a short run to the levelest place I know, the dam wall at a nearby reservoir. Here's a pic. Road to cill is 1 phone and 2 fingers at the rear, 1 phone and 1.5 fingers at the front.

Jacking up the rear had no effect on front camber.

View attachment 444180

I like the measurements, strangely to me looking at the photo I would have said there was more space between the tyre and wheel arch at the front.
It would be interesting to here what measurements should be, even though as you say it made no difference with the back slightly raised.
I did have a similar model complete with sunroof albeit a much more faded factory red and in tired condition back in the late 70s, first wife called it Oty on account on the last digits of the Reg.
Do you know what the correct camber setting is and what adjustment there is, as off hand I can't recall?

 

[smart51]

Camber should be 1° +/- 20'. Toe in should be 0-2 mm according to Haynes.

Camber can be adjusted by unbolting the top wishbone and changing the number of shims. You can adjust the camber the same way by changing the number of shims under the front or rear bolt on each side.

 

[Goldnrust]

I accept tracking often accounts for wear on the tyre's edge, however if you look at the tyre in the photo there is no sign of "feathering" which usually accompanies excessive "toe in" in cases like that.

Fair enough, I'm far from an expert and only have my own amateur experience to guide me.

Camber should be 1° +/- 20'. Toe in should be 0-2 mm according to Haynes.

So you've actually got less positive camber than the standard spec and so even less likely that is the cause of the wear pattern.

 

[bugsymike]

Camber should be 1° +/- 20'. Toe in should be 0-2 mm according to Haynes.

So as @Goldnrust says , within spec. for Camber. Just to rule it out what is the tracking reading?
If that is also within spec. do we put the tyre wear down to cr*p tyres and mad driving.
In the 70s we had customers with new Ladas who could wear out tyres in 600 miles, but that was due to badly set factory steering geometry and Russian tyres, which strangely wore out quickly and also didn't hold the road at the same time.

 

[the hobbler]

So as @Goldnrust says , within spec. for Camber. Just to rule it out what is the tracking reading?
If that is also within spec. do we put the tyre wear down to cr*p tyres and mad driving.
In the 70s we had customers with new Ladas who could wear out tyres in 600 miles, but that was due to badly set factory steering geometry and Russian tyres, which strangely wore out quickly and also didn't hold the road at the same time.

As Peter mentioned, the toe-in (0 degrees) should be set with a goodly amount of weight in the front of the car. Looking at the picture of your car, I wouldn't have thought that the ride-height was too far out WITH THE CAR EMPTY----put a couple of people in it and the front will come down. An important detail to remember---the track-rods must of the same length when the toe-in has been set. It is very easy to have one track-rod longer than the other (I have seen 'proffesionals'do it)---having the track-rods of unequal length will upset the steering and might even cause tyre squeal when cornering---al to do with the "Ackerman effect"

 

[bugsymike]

As @the hobbler mentions re track rod adjustment , many times I have found cars with one screwed right in and the other almost clinging on to the last threads due to a fast fit fitter?
Often adjusting one side only and if watched rattles his spanners at the back of the wheel on the other, another reason I don't approve of bonus systems especially in safety critical situations.
Calling them "Technicians" is an affront to time served motor engineers everywhere.

 

[smart51]

Having tried it, I can't say I'm a fan of the clamp a piece of wood to each wheel method of wheel alignment that Haynes suggests. Not for fine adjustment anyway. But when the toe in was set to 20mm, things can be improved a bit.

 

[bugsymike]

Having tried it, I can't say I'm a fan of the clamp a piece of wood to each wheel method of wheel alignment that Haynes suggests. Not for fine adjustment anyway. But when toe in is set to 20mm, it can improve things a bit.

View attachment 444263

I agree , but am fortunate I still have my Dunlop Wheel Alignment Gauge.
What was the reading for alignment when you checked it?
As if you are increasing that more to "toe in" 20mm that would increase wear on the outside of tyre.

 

[smart51]

Post reworded for clarity. It was set to 20mm of toe in. The RHS track rod was 10mm shorter than the left. Equalising the lengths reduced most of the excess toe in. A smidge more on each side and toe was reduced to 2mm.

 

[bugsymike]

Post reworded for clarity. It was set to 20mm of toe in. The RHS track rod was 10mm shorter than the left. Equalising the lengths reduced most of the excess toe in. A smidge more on each side and toe was reduced to 2mm.

That sounds better, I suppose you could go to the 0 degree and still be within tolerance, but I am sure what you have found and corrected will be an improvement.

 

[Goldnrust]

Wow 20mm toe in!

Steering should feel a fair bit more responsive now you’ve adjusted that out. Might even gain a touch more speed without the drag if scrubbing the tyres that much.