Technical Steering tracking (again)

Currently reading:
Technical Steering tracking (again)

DaveMcT

Distinguished member
Joined
Sep 14, 2009
Messages
19,492
Points
3,294
Ive checked the threads but this is a bit different.

I anyone else finding their Panda is scrubbing out the inside edges of front tyres?


On both Pandas, the steering wheel is centered ok and tracking was set/checked when tyres were fitted. 1.2 had new tyres in September 2017 and tracking was set to Fiat spec. Both are scrubbed away the inside edges both about the same suggesting it's centralised but effectively toe out.

Fiat spec is 0 degrees +/- 10 minutes = wheels parallel.

Mine had done similar things but the old tyres were ditch finders so not a good comparison. I recently had 195-50-15V fitted and the tracking checked. All ok apparently. BUT the inside edges of my new tyres are warm and there is a slight pull to the left.

One Panda in the family doing this fair enough, but both is strange indeed. Especially, as mine has not been adjusted since I bought it and tyre fitter says the tracking is correct. The threads on mine are b****xd so I have new track rod ends and track rods to fit so we will see how it is with them on Fiat settings. I suspect no different but at least I will be able to make small adjustments that are not possible right now. I plan to try it at the toe in end of the scale and go from there.
 
Last edited:
my girlfriends 100hp does this. a couple of MOTs back i had a quick look at the tires and the treads looked ok. took it for the MOT and it was badly bald on the inside. 1 was slightly worse than the other.

it has done it again and the tires will need changing soon becuase of it. i think its just how they are :(
 
my girlfriends 100hp does this. a couple of MOTs back i had a quick look at the tires and the treads looked ok. took it for the MOT and it was badly bald on the inside. 1 was slightly worse than the other.

It has done it again and the tires will need changing soon becuase of it. I think its just how they are :(

I'm sure you are right, but I plan to make small adjustments and see how it goes. The car pulls left very slightly so we will see if 1/2 a thread toe-in on each side helps.
 
Ive checked the threads but this is a bit different.

I anyone else finding their Panda is scrubbing out the inside edges of front tyres?


On both Pandas, the steering wheel is centered ok and tracking was set/checked when tyres were fitted. 1.2 had new tyres in September 2017 and tracking was set to Fiat spec. Both are scrubbed away the inside edges both about the same suggesting it's centralised but effectively toe out.

Fiat spec is 0 degrees +/- 10 minutes = wheels parallel.

Mine had done similar things but the old tyres were ditch finders so not a good comparison. I recently had 195-50-15V fitted and the tracking checked. All ok apparently. BUT the inside edges of my new tyres are warm and there is a slight pull to the left.

One Panda in the family doing this fair enough, but both is strange indeed. Especially, as mine has not been adjusted since I bought it and tyre fitter says the tracking is correct. The threads on mine are b****xd so I have new track rod ends and track rods to fit so we will see how it is with them on Fiat settings. I suspect no different but at least I will be able to make small adjustments that are not possible right now. I plan to try it at the toe in end of the scale and go from there.
Hi Dave. There's a big danger of me sounding like a "know it all" here, and that is most certainly not my intention. However I have worked with tyres (Firestone) in my early years and I have always been interested in them and how they interact with the vehicle. You may have read an earlier post I did where I described the tracking gauge I made myself.

You may know (so apologies if I'm telling you how to suck eggs) the appearance of the tread itself can tell you quite a lot about what's making a tyre wear - as long as that tyre has not been moved around on the vehicle of course. So lets consider we are sitting on the ground, in front of the OSF (driver's side front) wheel looking back towards the car. The first thing to consider is the overall wear pattern. Is it even across the width of the tyre or more worn in some areas than others?

Again apologies if I'm being too simple here but heavy wear in the centre but not on the shoulders is usually down to over inflation and the reverse, heavy wear on both shoulders but not the centre will be under inflation. This of course is easily rectified and eliminated in future by a weekly tyre pressure check.

Now, again sitting in front of the wheel and looking at the tread, perhaps left (outer) shoulder or right (inner) shoulder of the tyre is worn. This might be due to the suspension and wheel hub (perhaps because of wear or damage to suspension) failing to present the face of the tread squarely to the road surface. It might also be due to the tracking being incorrectly set or wear in the steering mechanism.

You tell us that it's the inner edges of the tread on both front tyres on your car which are wearing prematurely. So now have a very careful look at the tread pattern on these tyres. Lets consider the Off Side (drivers side) first. Ok, we can see wear of the inside shoulder but now look carefully at the treads over the width of the tyre. There will be, on most designs, bands of tread separated by water dispersing grooves which run right round the tyre. Look carefully at each of these bands, especially the edges of each band (some call them tread blocks). The inner and outer edges of each of these bands of tread should look the same (exhibit the same wear pattern) if your tracking is set such that it is allowing the two wheels/tyres to roll down the road parallel to one another. If you have this situation but with excessive wear on the shoulder then it's because the tyre is not being presented to the road surface squarely and it's likely the Camber angle on that wheel is incorrect. (top of tyre/wheel leaning in too much) If both front tyres are showing the same wear pattern (you seem to be saying both of your fronts are worn on the inside) then this is unlikely to be the reason as it's unlikely you will have an identical camber problem on both sides.

Given your wear pattern, it's more likely that your examination of the tread bands will show the inner edge of each tread block to be rounded slightly and the outer edge to be lipped. This wear pattern will form when the tyre is spending some, or all, of its time NOT rolling parallel to it's pal on the other side. Bear with me on this please. I know you believe your tracking to be correct. The wear pattern described will come about if both front wheels are toed out - ie splayed out (by even a small amount) The most likely reason for this is that the adjustment, made by adjusting the track rods where they screw into the track rod ends, is incorrect. But you know yours is right don't you, because it's been checked. By the way the opposite will be seen if there's too much toe in - ie the front wheels are "snow plowing" (wear on outside shoulders and outsides of each tread block rounded with inside edges lipped). It's not unusual to find when there's too much toe out that the inner shoulder of the O/S wheel is more worn than the inner shoulder of the N/S and where too much toe in is the problem the outside of the N/S tyre will be more worn than the outer shoulder of the O/S. This is simply due to road camber. - Think about it for a minute but just ask if you can't figure it out.

So now, perhaps, you're sitting thinking well, I do see some signs of this "lipping" effect but I know my tracking is correct, so what's going on? We have to face up to the fact that if the treads are lipping then, at least for some of the time, the two wheels/tyres are not rolling parallel! Having done more wheel alignments than I've had hot dinners my first port of call would be "show me the read out" Modern aligning rigs can produce a before and after read out which you should always request. There are many things which can interfere with the accuracy of a wheel alignment but the machine (if in good order and calibrated) can't lie. Also the technician doing the job MUST first do a thorough and rigorous check of all suspension ball joints, rubber bushings, steering swivels (macpherson strut top mounts being one such) and look for accident damage. If we assume the machine thinks it's correct then it's likely that the wheels are conforming when the vehicle is standing still but, and I've found this to be not uncommon, The suspension arms on most cars today use rubber bushings where they pivot on the chassis/subframe. These can look to be in good condition visually but in use, because of age and use, they can become "squishy" and overly flexible - There is a thriving business in "performance" poly bushes which are generally stiffer for the performance minded. If this is the problem then when just rolling along the track will be more or less OK but under braking, especially anything more than gentle braking, The drag of the retarding wheel will drag the front of the arm outwards, the bushes compress excessively and allow the wheels to toe out so giving the effect you are seeing. It's quite difficult to diagnose this one with certainty but it can be remarkable how different an otherwise OK handling vehicle can feel after renewing its suspension bushes!

A chap I used to know had a Gunson Trakrite. - I've just googled it and its still being made, now identified as a Gunson G4008 Trakrite - It consists basically of two plates with ball bearings between them (think they're ball bearings?) which you drive one wheel of the car over. The other wheel is still rolling along the ground so if both wheels aren't "tracking" parallel then the top plate slides sideways and registers it on a pointer type gauge. I've used it a number of times and found it very good because, regardless of what the vehicle manufacturer quotes as a toe in figure, the gauge will pick up if the wheels aren't rolling parallel! (I want one, It's on the wish list) I know some performance extremists intentionally introduce toe to alter handling but we're talking standard vehicles here so all i'm wanting is for the tyres to wear as slowly as possible!

I'm beginning to see spots in front of my eyes now! so maybe it's time to stop. We haven't even thought about Caster, King Pin Inclination, Toe Out on Turns and a whole lot more but this has been a start. Have a chew on it and get back to me if you like.
 
My ? hp is wearing the inner os/f tread and pulling to the left, I had it 4 wheel aligned on a Hunter and the tracking was spot on apart from the os/f having a degree more negative camber than the ns/f.
Going to give it a suspension refresh soon, see if that solves it.
It's on 44000 miles. 10 plate.
 
Hi Jock.

Thanks for that information. Very interesting. I see the lipping and cupping regularly on motorbike tyres. Soft compound and rapid wear compared to car tyres. The tread blocks wear faster on the trailing edge so they appear stepped. The leading edge gets slightly rounded off.

Bikes wear the shoulders on the front tyre faster than the mid-line so the originally round tread shape becomes sort of V shape. This is because bikes steer differently. They use tyre generated forces to lean the bike into and out of a turn. The steering is momentarily turned the "wrong" way to generate the cornering force. On a big bike, this loads the tyre quite heavily.

Cars should present the tread flat to the road though race cars often have a lot of negative camber. That allows cornering body roll to level the outside tyre so it's tread goes down flat while it's cornering. Check out pictures of Schumacher's Benneton).

I did not closely examine my Panda tyres and I can't check Mr's Dave's as she having her's replaced this morning. Both cars hammered the inside shoulders on both fronts.

I suspect the 169 Panda has a little negative camber which puts more load on the inside edge of the tyre. It's easy to check with a spirit level angle finder against the tyre side wall but accurately leveling the car could be fiddly and it wont have the precision of a professional tracking gauge. Negative camber (in at the tops) makes the steering heavy to turn but with power assistance its no problem. The old BL MIni had positive camber (out at the tops) to ease steering loads but the pay-off was understeer and tyre wear. Longer bottom arms were a common tuning mod. David Vizard's books explain it well.

The 100HP on it's new rubber, definitely has more warmth on the inner shoulder than outer so I'm pretty sure adding a little toe angle will help but it will need the new rod ends and track rods to do the job accurately.
 
Last edited:
What tracking tools do you have?

I use two types. One is an ancient adjustable rod with cranks at both ends, for measuring road wheel alignment at the rims (fore and aft), and this has a 'micro' pointer on it that is supposed to measure in very small increments, and the other is a Gunson Trakrite.

When setting tracking, I use both. I also ignore the Fiat recommended setup, because although this is no doubt correct for a new(ish) car, it can give a false reading with a car that has general suspension wear after a few thousand miles use on our adorable roads.

So, after aligning the wheels/steering wheel so that the car drives 'neutral', I then set the tracking (using the Trakrite) to give a very small toe out bias.
 
What tracking tools do you have?

I use two types. One is an ancient adjustable rod with cranks at both ends, for measuring road wheel alignment at the rims (fore and aft), and this has a 'micro' pointer on it that is supposed to measure in very small increments, and the other is a Gunson Trakrite.

When setting tracking, I use both. I also ignore the Fiat recommended setup, because although this is no doubt correct for a new(ish) car, it can give a false reading with a car that has general suspension wear after a few thousand miles use on our adorable roads.

So, after aligning the wheels/steering wheel so that the car drives 'neutral', I then set the tracking (using the Trakrite) to give a very small toe out bias.
If you go to the Tech Talk section, about 3 pages back, you'll find a wee feature "Jock's tracking gauge" which is dated 24-6-18. In it you can see my home made gauge. It looks ridiculously simple but don't laugh too hard, it works a treat!

On my own and "family fleet" vehicles, where the history is well known and most of the work on them is done by me, I find observation of the wear patterns very helpful indeed and, as you say, I would tend to use manufacturer's recommended settings as a guide but modified by the actual wear pattern developing on the tyres.
 
Mine always wear a little more on the inner edge, despite several 4-wheel computerised alignments, with before/after readings.

From similar posts over the years, there was an opinion that it was just that the Panda chassis was made poorly, and this is how many are. With that in mind, adjusting and measuring may just drive you mad.
 
Hi Bill. You are not wrong there. The back axle looks like the factory had an Aldi 140 stick welder and a hacksaw.


I dont have the tracking data for mine (forgot to ask for it)

Mr's Daves has a -2.15 camber on the right front and near enough vertical on the left. In effect one bottom arm is too long (or the other is too short), so something is going on there. The toe has been set to 0 degrees dead one side and within 1 minute on the other so they are straight ahead.

The car is very clean and there are no signs of any body repairs anywhere so it's likely a bottom arm is on the way out. At least her's are cheap.

The same fitter did my tracking, told me it's set to straight ahead.
 
Last edited:
Mine always wear a little more on the inner edge, despite several 4-wheel computerised alignments, with before/after readings.

From similar posts over the years, there was an opinion that it was just that the Panda chassis was made poorly, and this is how many are. With that in mind, adjusting and measuring may just drive you mad.

After I did my punto front subframe and the steering wheel was no longer straight ahead I was later wondering if I would have got a better result by not touching the tracking and instead moving the subframe. I was not even thinking of that when I did the car. For the time being I am going to leave it all alone and see what happens to the tyres.
 
The steering wheel should be set straight ahead and tracking adjusted at each side to correct the wheel's toe angles.


Open the car windows, put a wood batten through and bungee cord the steering wheel to the batten. It's now can't move while you make the track rod adjustments.

Professionals have a simple to use tool for the job.
 
The steering wheel should be set straight ahead and tracking adjusted at each side to correct the wheel's toe angles.


Open the car windows, put a wood batten through and bungee cord the steering wheel to the batten. It's now can't move while you make the track rod adjustments.

Professionals have a simple to use tool for the job.

I adjusted the tracking in the usual way.

I am now wondering if I could have got a better result by adjusting the subframe.

Your tracking is straight ahead and your tyres are wearing. Bill said there was an opinion the Panda chassis is so bent that adjusting may drive you mad.
 
Last edited:
If I'm not feeling lazy I set the tracking myself using Dunlop alignment gauges. They do a great job and have been far happier with the results from that that some new fangled laser thing that the 14year old "technician" has no idea how to use.
 
I've always found my fronts wear out the inner as well despite me always getting the tracking done.

Funny enough I always ask for a copy of the tracking sheet but I have no idea what I'm looking at ??
 
I've always found my fronts wear out the inner as well despite me always getting the tracking done.

Funny enough I always ask for a copy of the tracking sheet but I have no idea what I'm looking at ??

If the machine is setup wrong it could have the correct readings but still be out!
Seems the way of the world now, poorly trained people doing half a job is now the new norm :(
 
When I had my panda( 205000 miles when I sold it) it used to wear the inside of the front tyres even at the first 5000 miles it was showing wear I had various firms adjust / check the tracking no difference so at around 60000 miles I bought the gunsons trakrite adjusted it myself ...SORTED ?
 
Getting the tracking right on Pandas is notoriously difficult.

I'd suggest you start by setting the front toe so the wheels are dead parallel - I made up a jig out of some bits of Meccano to do this, but you can use anything so long as it's absolutely rigid and fits round the subframe. You can get it accurate to better than half a millimetre at the rim and that's well within limits. Then see what happens to the tyres. If you really do know what you're doing, you'll know which way to go, perhaps half a millimetre at a time. Once the tyres aren't wearing unevenly anymore, stop.

You won't get everything perfect unless you're prepared to start undoing the rear subframe bolts & messing about with shims at the back, but it'll be 'good enough' if you just get the front toe right in 95% of cases.

The moral of the story is that if your Panda is wearing its tyres evenly, under no circumstances let anyone mess with the tracking, even if their laser tracking gauges say it's miles out.

Simple basic tracking tools in the right hands will get you a better result than £20,000 worth of laser tracking kit and an inexperienced operator.
 
Last edited:
Back
Top