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MG MGF Technical - Uneven tyre wear despair!

Just over one month ago (26/7/01) I replaced the front tyres (SO-2's) on my F with smoe new shiny(?) SO-3's due to their early demise due to uneven tyre wear - tracking previously having been set to minimum toe-in spec (only lasted just over a year). On the 8th of this month a four-wheel alignment was again performed on my F with the requested settings of -5 mins on the front as recommmend here. Now just 3 weeks later and approx 750 miles later the frnot tyres are already showing early signs of uneven wear!

Looking at the before and after settings of the wheel alignment things are far from promissing either. Before measurements show that the front wheels (with SO-2's fitted) were toeing in -14 mins. Naturally as I'd asked for the tracking to be set -5 mins on the fron that's what they now are, and this naturally is only making matters worse. At the time I was assured the ride height would be corrected if necessary before the tracking settings were altered - I'm now wondering if this was done or if it was if the ride height has dropped already, currently measuring around 355 on the fronts though this was after driving the car so it may not be very accurate?

My next door neighbour works on cars front his garage and actually has a two wheel alignment jig and for the hell of it he checked the front tracking with this and indeed it did show the front wheels to be toeing in -10 mins combined. Thing is this was at the car's current ride height - ie. just out of min spec.

I was surprised how much difference lifting the front the car (manually grabbed bumper and lifted slightly) made to the tracking settings - buggered if I can remember which way the tracking went now though? :(

Now I find myself in one of those situations where you've really had enough of paying good money only to have more tyres wrecked prematurely. So I see my options as follows.....

1. The car is for it's 3 year service in about three or so weeks - Do I get them to reset the ride height and tracking to min spec again. Going by the alignment read-out the spec for the front is now -4 to -15 mins per side on the front!

2. Get my neighbour to set the front to -15 mins (or more!) regardless of ride-height - doing it via the dealer seems to be a waste of time. Shame - no real problem with Priests before, and they've only set the tracking as per my request anyway. :(

3. Get shot of the car for a Y2K model - though I want to know whether Y2k owners are still suffering from uneven tyre wear. I was kind of planning to see what happens with regards to the MK3, but the way my tyres are wearing I'll need a new pair on the front well before they are available.

4. Techspeed the suspension. I've added this so other people do not suggest it - I've already ruled this out due to expense+hassle of insurance and selling on the car as I've kind of decided to chop it in in the next year or so now anyhow.

Currently very miffed as this is the only real issue I have with my car. But it's a bloody expensive one both in cost of alignments (£70 a throw at my dealer) plus new tyres prematurely - currently wishing I'd not bothered to get SO-3's and kept to the cheaper NCT3's crap I know, but tyres are a waste of money ATM. TO make matters worse my rear tyres also need replacing. :(

All sensible comments and suggestions welcome.

Paul Lathwell
S381 GBW.
Paul Lathwell

Paul,

I'm afraid and woun't have right here, but
minus angles are in my opinion Toe OUT .
http://www.lame-delegation.de/mgf-net.de/tracking/b249a.gif

Dieter
Dieter Koennecke

Are the other suspension settings - especially camber - in spec ? You may want to consider replacing the subframe mounts / suspension bushes, depending on the age of your car.
It may be worthwhile taking the car to an independent specialist, such as B&G, Mike Satur etc.

Steve
Steve

Paul,

Little comfort to you I know, but I've been there, done and have the T shirt having gone through 6 (or was it 7?) sets of tyres in 28,000 miles.

As you know option 4 was my solution. You could ask Techspeed just to set the tracking to their spec. (Whatever that may be). They will do this but I'm not sure how much they charge, but you'll save the cost of the Bilstein shock absorbers which are about £100 per corner.


Paul
P9 VLS
Paul

Wear in ball joints will throw a spanner in any suspension setting and allow significant alteration of suspension geometry when in use. The wear may not be excessive, but enough to generate sufficient 'float' to see enough change to give problems with the tyres.

Another thing I suspect is whether suspension height adjustment is done correctly. The main issue being sufficient settlement time at an adjusted setting to cofirm the correct height. Allowing the car proper standing time after adjusting and a settlement drive is the only way to confirm this. Once this has been done then geometry adjustment will have a longer term effect.

Finally modifiying the suspension to include stiffer dampers and lower ride height does reduce the range of normal travel in the suspension in use. As there are wide geometry changes in the arc of suspension movement any reduction in the normal range of this arc will also reduce the variation of angle changes. In turn this reduces the effect on tyres.

Rog
Roger Parker

I also seem to recall, Roger, that you pointed out a long time ago that wear in the standard rubber suspension bushes would lead to great variation in the tracking settings. I seem to remember the concept of "set tracking, drive round the block, check again and its already out".

That was one of the reasons I opted for getting polybushes fitted. My F had (only - in my case) eaten 2 sets of fronts in 30 something thousand miles with uneven wear.

The dealership had replaced a lower arm and reset the tracking, but it didn't help.

I had the polybushes fitted last November (obligitory ad for Meltech!) and he set the tracking to the BBS settings (5' in at both ends) "the racing way" (with string and a ruler!). Since then ~10k miles to date and perfectly even tyre wear - I haven't measured the tread but there's still loads left on the front: the rears will wear out first.

I know its not a cheap option, (£150+ for the bushes, then fitting and tracking which is a couple of hundred at Mel's prices) but its worked brilliantly for me (and that's discounting the better handling...). Has also saved on expensive tyre replacements so far.

I should point out that B&G STILL haven't managed to provide the anti-roll-bar bushes in 11 months, so maybe they aren't the place to take your shopping list to.

I told the insurance company that I had fitted "long life" polybushes, stressing that I was replacing worn standard components with better quality and they didn't load me at all.

Good luck,

Neil.
Neil

I'll take my car for service in 2 weeks.

I have a difference in ride height (left hand of the car being higher than right hand).
I will ask for the system to be checked and ride height to be adjusted.
As far as I remember from previous threads, 4 wheel alignement must be done just after.
What are the latest values MGRover recommend for toe (front and rear)?
The latest values I have in mind are:
Front : 0°5' +/- 5'
Rear : 0°10' +/- 6'

Thanks
Jerome
Jérôme

Paul, can you verify whether the front wheels are toe- IN or toe- OUT. As Dieter says, your figures suggest toe- OUT- and in this case I would urge you to reverse this to toe- IN. There are now a significant number of cases whereby this simple expedient has solved the tyre wear problem.

Suspension component wear would indeed cause problems as Neil and Rog correctly point out- but the fact that your neighbour friend (whom I presume is competent with the measuring rigs he has got) measures and verifies the geometry that the dealership are said to have set may argue against this.

Couple of things you haven't mentioned: camber and castor. What are these values Paul?

BTW the "difference lifting the front the car (manually grabbed bumper and lifted slightly) made to the tracking settings" is caused by a phenomena called 'bump steer" Unfortunately, the front suspension is somewhat plagued with this phenomenon- as is the rear unless rear tie-bar compliance washers are fitted.

HTH

Rob
Rob Bell

This is simplistic advice but I can't recommend Techspeed highly enough. They lowered my car and set up the tracking and tyre wear is very even - handling much improved. £150.

At the very least they may be able to diagnose the problem.
James

Paul,

>>>>Get shot of the car for a Y2K model - though I want to know whether Y2k owners are still suffering from uneven tyre wear.

Well, my advice is also pretty simplistic, as you'd expect. I have a Y2001 car, and the alignment was crap when I got it - very noticeable even to someone like me. Took it to B&G and they seem to have cured it - no more pulling, no more uneven tyre temperatures and no evidence of uneven wear at 6K miles (I know - hardly enough to tell, but the inner edges were clearly warmer after a fast run).

I deduce from this that the Y2K is fine (from my experimental sample of, er, 1), *as long* as it is aligned properly. I asked B&G and they didn't think the settings they'd made should 'wander' in the near furture.

I don't know if they did more than most places would, but the printout they gave me showed that they'd checked, and in come cases altered camber, and various other things I'd never heard of. If you want a copy of the printout they gave me, then get in contact.

As I'm sure you know, they do the knuckle lowering, which many say is not as good as the TechSpeed system, although I wouldn't know. They are, however, nearer you. I'd probably get them to do it for personal reasons (i.e. they're 2 miles away and will be doing everything else on the car).

David Bainbridge

Rob,

recalling confusions between us about one year ago.
Many thanks for the confirmation :)

I assume this case is only the 'peak of the montain' and if applicable than a lot of MGF get still adjusted to the wrong direction.
No panic, but should be verified.

Jerome,
go for it.
Traccking adjustment must not be made 'just after'. Better is to drive 100 miles before you do.

HTH
Dieter
Dieter Koennecke

Hmmm, seems I at least need to contact the dealer again and speak to the technician and NOT the service staff. When I booked the car in I did say I wanted the front wheels toed in to -5 mins each side, perhaps this is where things have gone wrong. ie. my saying -5mins when it appears this should have been +5mins per side to get the front wheels closer together at their front egdes and further away from each other at the rear.

I'll have a word with the technician and go from there. ATM, I'm just left with the feeling that whatever I have done to my current F that I'll never really be happy it has been sorted. :(

Cheers for all the comments. :)
Paul Lathwell

Hi Paul,

I have a March 2000 VVC and at 3500 miles the back tyres were bald and since I had bought the demonstrator I had only actually done 2000 of those). I insisted that Faraday Rover replace the tyres under warrenty and "sort it out"(I was buggered if I was going to pay £300 for 2 tyres - Their cost not Michel Devers). Blow me if at 7000 miles the back tyres were bald again and the front had joined the party. Needless to say I was furious. Faraday Rover agreed to replace the back tyres but said I had to pay for the front (Cue Michel Dever £150 for 2 F1s). When they delivered the car back to me I also noticed that the ride height had been moved up (about 3 inches).

Apparently the saleman had had the suspension lowered. at nearly 15000 miles there have been no further occurences but the car corners like my Mums Volvo (Ok _slight_ exageration but its not as good as it was). However it is much more enjoyable to drive. I think what I'm trying to say is that I agree with David, if a Y2k model is set up it seems to have no problems, but then I guess the same is probably true for the older cars as well. Me? I'm saving for tech speed. I want to be able to go round corners faster.

Just one question, why do you think that it's more hassle to sell the car after Tech speed have done their thing? I would have thought that it should have added to the value.

Chris.
Chris Ponder

>>>why do you think that it's more hassle to sell the car after Tech speed have done their thing?

Well, its a modification, and most buyers are pretty mod-averse. And unlike a K&N it's not a mod you can remove if s buyer wants. And it might increase the insurance...

*YOU* know and *I* know that it's an improvement, but Mr/Mrs cautious car-buyer often doesn't like that stuff.

Sorry to butt in.
David Bainbridge

"lowering" definately seems to be something that the insurance co's are interested in - even though they don't realise that F's go up and down dependent on the temperature.

Really depends on how "straight" you would be with a buyer... Do you tell them its lowered and by how much, or do you let them discover what breaks when a dealer tries to get the car back up to 368mm and blows assorted seals in the process.

HOWEVER, they don't seem averse to bush changes and other things that will improve durability and probably help handling in the longer term (because they don't wear out!)

Neil.
Neil

Update....

Having looked again closely at the most recent set of readings for the tracking on my car it would appear as suggested that the front wheels are still toed out rather than in as requested. Having looked at the figures again in conjunction with the WSM, it does seem quite obvious that this is the case.

For those interested I've uploaded a scan of the before and after readings to the Fotofile section of my website......

http://www.dotcomoff.demon.co.uk

Also spoke to the dealer - but more on that later, TG is on and there's a storm outside - bye for now! :)
Paul Lathwell

Hi Paul,

Noticed Priest's are your MG dealers in Chesham, you may already know, but Merit Tyres in Amersham/Little Chalfont - about 5 mins drive from Priests USED to do all their 4 wheel geometry checks before MGR insisted that all dealers should ahve their own kit. Had my MY2000 F done by Simon Newton (technician at Priests) sost about £60 I think, Merit will do it for abot £40-£45. A little better and they have long experience with F's.

FYI my 2000MY was out when it was checked - actually still out when they gave it back ie one of the "green boxes was still red camber (-1 degree 51 min)" for the rear drivers wheel, also did they advise you to have a FULL tank of petrol when the geometry is done, as this is latest MGR advice apparently.

Cheers
Neil
Neil

Cheers Neil - I knew about Merit's in Amersham and have considered giving them a try, though I've always found Simon very helpful and willing to listen and never had any reason to doubt his ability. TBH, I think I just have noe of those unlucky F's when it comes to front tyre wear and as for the lastest settings I think something has been lost in comunication with regards to what settings I wanted set on the front wheels. That said though I will bear Merit's in mind for future use, but TBH, if the car plays up again after having the tracking redone (yet again) I'm certainly going to give up on it and trade it for a newer model.

I went over to Priests today and had a word with both Kevin an Roy on the service desk about the problem and what could be done. The upshot is that they'll contact MG/Rover for advice on what to do to try and cure the problem, and will recheck the ride height and tracking at the next service in a couple of weeks. Though depending on what MG/Rover have to say they will try and fit me in next week - I'm going to the lake district the week after and I don't intend to come back with trashed front tyres. If it comes to it I may well ask the neighbour to adjust the tracking in for me - ie. give it a go myself in the hope it will at least reduce the tyre wear until Priests can check the tracking again at the next service.

As I say if front tyre wear persists then the car will go basically, ie. cut my loses and hopefully get some faith back with a newer car. I've already thrown a few figures around with Kevin to get some idea of the expense though, I was hoping the expense would be lower. <shrug>

http://www.dotcomoff.demon.co.uk

Home of the MG Dealer Guide, F'ers Gallery and new MGF FAQ (one day honest!). :)
Paul Lathwell

Hmmm, this 'after' values don't look that dramatic bad (IMO)
The values 'before' (-28'!!!! result in inner wear, no doubts !!
http://www.dotcomoff.demon.co.uk/home/motoring/fotofile/before.jpg

Still Toe Out at the front.
http://www.dotcomoff.demon.co.uk/home/motoring/fotofile/after.jpg

compare with John Thomas. (one year old)
http://www.bath.ac.uk/~ccsjst/mgf/after.jpg
(copy&paste this or use http://www.lame-delegation.de/mgf-net.de/tracking/technik.htm and than 'MGF Sample' on the bottom to John Thomas site)

The front left and rear right camber at Pauls car make me wonder, but such differences in camber are not seldom.

Not sure about it, but they should adjust +5' to the front in any way.

Any thoughts on the cars left front camber ?
+5' at the front will probabbly compensate the small camber, will it ?

Regards
Dieter
Dieter Koennecke

Paul,

Having read your last posting I fully sympathise with the troubles your having.

My N & R reg F's were so much trouble with tyre wear that I just gave up and cut my losses last year and bought a 2000MY. It seems there is a multitude of things that could effect the tyre wear. I remember one of the converstions I had with Terry (service manager) who was considering an entire new sub frame at once stage!

Difficult decision when to replace the car, I am looking to hold onto my F until spring/early summer next year then sell it in readiness for the new MkIII when it comes (supercharged one hopefully subject to how much!).I put cheap tyres on my old F to "keep it going" until the season was right to sell.

Priests are IMO a little notorious for very "hard" deals on new cars. I had to go to Wadham Kenning in Guildford (now closed unforunately)to get a satisfactory deal on my new one. Priests couldn't come close.

Best of luck which ever way you jump.
Cheers
Neil
Neil

Cheers Neil.

I do now have an update on the situation....

Basically I borrowed the two-wheel laser alignment equipment off my neigbour today and have played around with the front settings so that the front wheels at their current ride height (343 left and 350 right - wrong I know) are now toe-ing IN a total of 7 minutes.

A more detailed list of what I tried/done........

1. The car had been in the garage all night - hand brake on. The car was revsered carefully out of the garage and slowly down the short but fairly steep ramp leading into the garage. With the car park and handbrake applied a basic measurement of the fron ride height was taken: 340 left and 345 right.

2. The tracking was then checked and gave a total toe-OUT of 20 minutes! This is twice as much as when I previously checked a few days before, though the ride height was higher then and the car had just been driven.

3. After initialy struggling to loosen the track-rod locking nuts (lack of room with car on the ground) first the front left wheel was ajusted towards toe-IN by 10-15 minutes - ie. the total toe-OUT reading was reduced to approx 5-10 minutes toe-out. Tightened the left track-rod locking nut then repeated the process for the right wheel and then had the front tracking set to toe-IN 10 minutes. Bearing in mind of course that the ride height of my car is clearly out of spec.

4. The car was then driven (naturally after making sure both track-rod locking nuts were tight!) for approx three miles. This was done for several reasons....
A: So the tracking could be rechecked after the car had been driven.
B: To see if the steering wheel was straight when driving in a straight line.
C: To see if/how the handling had been effected.

5. Having returned from the test drive the front tracking was re-checked, it was now showing a total toe-IN of approx 20 minutes. As the steering wheel was very slightly off-set it was decided that only one wheel would have it's tracknig changed, both to reduce to toe-IN to 10 minutes and to straighten the wheels in relation to the steering wheel.

6. A second test drive proved the adjustments had corrected the straightness of the steering wheel in relation to the front wheels in the intended direction.

7. The front ride height was again checked after the second test drive - and yes I KNOW this is not how it should be done - it was done for simple comparison. Readings now showed 343 left and 355 right.

8. Without bouncing the suspension at all the front tracking was checked again, this time the total toe-IN reading being 7 minutes.

9. The front suspension was then both compressed and raised by manually pulling up and pushing down on the front of the car slightly. Doing this caused the readings to vary slightly between very slight toe-in (nearly 0) and to between toe-IN 15-20 minutes. Generally speaking though the car would normally settle back to the same place with the front Toe-IN showing about & minutes.

10. Out of curiosity I used a trolley jack under the left sill to raise the left side of the car until the ride height measured 360. The right hand side of the car was simply lifted and allowed to settle at 360. ie. both the left and right ride height measurements were now 360mm. The tracking reading was taken at this and showed a toe-IN value of approx 22 minutes!

11. Again with the trolley jack removed and bouncing the suspension at the front and allowing it to find it's own height returned the tracking settings back to toe-IN of 7 minutes. The conclusion being that at the CURRENT ride height the front wheels are toe-ing IN by a total of 7 minutes.

CONCLUSIONS......

A: Although the ride height was NOT checked following the method as outlined in the workshop manual I am convinced the ride height of my car is too low and probably was not adjusted as I was told it would be when I had the dealer perform a four-wheel alignment about three weeks ago.

B: Although the ride height of my car is low and the tracking has been set in toe-IN 7 minutes at this height - I'm happier that the front wheels are at least toe-ing IN rather than toe-ing OUT. The previous Toe-Out setting WAS causing premature tyre wear due to the inner edges of the tyre being worn faster than the rest of the tyre. Naturally the effects of the current tracking settings can only be proven by driving the car and keeping a VERY close eye on tyre wear. It is my opinion that the inner tyre wear will either have been reduce substancially, eliminated or that the tyres will now start to wear on the outside edges.

C: Ultimately, I now need the dealer to check the condition of the hydra-gas system/units and re-set the ride height both using the correct method AND to the correct height. Then and only then should the four-wheel alignment be checked and as and where necessary adjusted so that the front wheels are set to TOE-IN by a total of 10 minutes (ie. toe-IN 5 mins pers wheel). Of course now I have taken this action myself and changed the tracking I guess I may have left myself open to them refusing to do any work FOC. In this instance I will be arguing my case very strongly, ie. my tyres wear being trashed due to a poor set-up and by toeing the fron wheels in I was attempting to reduce this until such a time as they could investigate further.

Now for your comments - but remember a few things. The ride height was NOT checked as it should be. The ride height was/is incorrect when adjustments were made to the tracking. Finally that the front wheels are TOE-IN 7 minutes at the car's current ride height in the hope of reducing or eliminating premature wear to the inner edges of my front tyres.

Comments please......


http://www.dotcomoff.demon.co.uk

Home of the F'ers Gallery, MG Dealer Guide and new MGF FAQ. :)
Paul Lathwell

This thread was discussed between 29/08/2001 and 01/09/2001

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