Wandering Z3?

[stewart.w]

We have a 51 plate Z3 which has 56,000 miles on the clock, it has just had an MOT, and an £800 service and
E36 wishbone bush set (£138). We have only owned it since October 2013. It wanders across the road, like the wheels are caught in ruts in the road, but usually there are no imperfections on the road surface and it doesn't do it in the same places (on the same roads). It appears to be almost random, so had the wishbone bush set replaced on the garage's recommendation. Do all Z3s do this, or have we got a bad one?
It just wanders when it feels like it and tends to pull to the left when it wanders. My wife isn't a good driver anyway and this just freaks her, so we may be getting a Mercedes if we can't cure it.....

 

[GazHyde]

Hi and welcome @stewart.w

To some extent all Z3s are prone to tram lining as you describe. There are many possible reasons why it may be doing it, bushes etc.

Tyres can be a factor as well, so what size wheels and what make of tyres do you have on the car?

 

[bruce&kim]

Mine used to do it all the time so changed the wishbone bushes to polybushes and its made a huge difference http://www.ebay.co.uk/itm/BMW-Z3-1994-2002-POWERFLEX-Front-Lower-Wishbone-Rear-Bush-PFF5-301/300840956341?rt=nc&_trksid=p2047675.m1851&_trkparms=aid=222002&algo=SIC.FIT&ao=1&asc=286&meid=3791081353146662808&pid=100005&prg=1048&rk=1&rkt=5&sd=290879991320& This thread helped me out http://zroadster.org/wiki/bmw-z3/modifications/bmw-z3-subtley-stiffening-a-z3-by-mike-fishwick/ although when it was written the bushes were not specifically for a z3 and had to be adapted the ones available now are.

 

[Mr-P]

As both above say check all suspension bushes and tyres(including pressures)

 

[zedonist]

Start simple, tyre pressures, then tyre sizes, 215 (on 15" or 16" rims) is the default size up front but most are fitted with 225 or even 235 (on 17" or 18' rims). I had 235 fitted on some aftermarket alloys and it tram lined badly, as you have described, i then fitted 225 and the tramlining went away on good roads. You won't remove the effect totally as it is a rear wheel drive car and also has a narrow track up front so will tend to follow road imperfections. certain tread patterns also seem to affect performance of the steering and a lot of people swear by Falken tyres.

Next up is checking the geometry, get the actual tracking checked as excessive toe in or toe out will cause it to wander.

After this you are on to the bushes, joints and drop links, the trailing arms have a number of ball joints on them that wear, and the rear bush goes soft with age, also the the top mounts on the suspension legs can wear loose,, this can all be remedied for under a £100 if you are mechanically minded and have the tools it is a nut and bolt type of job. I have replaced all bushes and joints on the front end of mine, and the car now tracks like a dream, but is still susceptible to poor uk roads.

 

[stevie_a]

Also had this I changed my tyres from Avon to Falken ZIEX ZE-912

now perfect.

 

[Aceman]

I have said it before that tyres are the single most common cause of this problem. Z3's are ever so sensitive to the make and type of tyre fitted to the front wheels you wouldn't believe the extent they have on eliminating this problem. As said above Falken's are good at eradicating this although think the ones available now are 914's with similar tread pattern. I have a set of Hancook's on mine which totally eliminated the wondering caused by the previous Pirelli's.

 

[zedonist]

Following several years as a successful tyre salesman to Z3 fraternity Aceman is quoted:

I have said it before that tyres are the single most common cause of this problem. Z3's are ever so sensitive to the make and type of tyre fitted to the front wheels you wouldn't believe the extent they have on eliminating this problem. As said above Falken's are good at eradicating this although think the ones available now are 914's with similar tread pattern. I have a set of Hancook's on mine which totally eliminated the wondering caused by the previous Pirelli's.

I'm Ron Burgandy and this is the GNN news update

 

[vintage42]

I have said it before that tyres are the single most common cause of this problem. Z3's are ever so sensitive to the make and type of tyre fitted to the front wheels you wouldn't believe the extent they have on eliminating this problem... I have a set of Hancook's on mine which totally eliminated the wondering caused by the previous Pirelli's.

My 1997 Z3 1.9 had the original tires when I bought it last year with 32,000 miles. It also had original Sachs struts and shocks. After replacing the tires with Hankook 225/50R16 Ventus V4 ES, the tram lining was greatly reduced, and new KYB struts and shocks made further improvement.

 

[miller1098]

Bushes worked for me.

 

[hard top]

I run on winter tires all year round, never had a problem.......

 

[t-tony]

When I bought mine the tram lining was so bad on our local roads that I initially regretted buying the car. When I drove it home from near Sheffield a lot of the journey was on the M1 and as I wasn't used to the car I didn't drive particularly hard so the problem really didn't show itself for a day or two. Anyway all the tyres weren't great and as I work for a tyre company and got a reasonable discount I replaced all 4. Result? Like driving a brand new car, I honestly could not believe the difference . Mine now runs on Maxxis tyres, 225/45x17 91W (MAV1) on the fronts and 245/40x17 95W (MAZ1) on the rear. The rear tyres have what is sometimes laughingly called tractor tread which does give reasonably better grip in poor conditions but are extremely quiet on most road surfaces apart from the dreaded granite chippings type.

 

[GazHyde]

There are a few of us running Maxxis MAZ1's here including me. Really pleased with them considering the price!

 

[t-tony]

I don't know how mine compare Gary but I paid £228 inc vat for the 4.

 

[GazHyde]

Mine are 225/40/18 and it was a while ago, but I think they were £75 a corner. Didn't have the luxury of time to look around for the best price as my wheels were in for a refurb, and they condemned 3 of the ones fitted!

 

[t-tony]

It never ceases to amaze me what condition tyres get in and quite often it's like a tyre of 2 halves. By which I mean the tyre looks absolutely fine from the outside but from the inside or underneath its a totally different picture and most people,when you show them cannot believe how bad their tyres are with wires hanging out and/or worn through to the cords.

 

[Mint]

There are a few of us running Maxxis MAZ1's here including me. Really pleased with them considering the price!

I'm running Maxxis as well, also very pleased. I've never suffered from the tramlining issue - and still don't

 

[joey]

Running maxxis on the rear and Bridgestone potenza on the front.

No tramlining to speak of ,but I still plan to upgrade all the bushes bit by bit..starting with wishbones this week,then subframe bushes or skunkworks inserts..arb bushes will be done when I replace the current arbs with thicker



ones.

Tony check out "a subtle stiffening" article by mike fishwick in the wiki..this covers most of the common suspension and handling issues that Z3's can commonly suffer from..

TBH my Z is still one if the better handling cars In it's class I have driven..despite Clarkson and co slating it at every opportunity....and with a couple of inexpensive adjustments can become a really well balanced car.

 

[stewart.w]

Thanks everyone for your suggestions, particularly tony-t, we too thought we had bought a "pup".
The car wasn't too bad on the initial drive but has become worse or we are just more aware of it. We thought there was
something seriously wrong with the car despite the £800 service, new bushes and MOT and assurances from the
BMW specialist garage. Anyway, thanks to your advice we have been looking at the tyres and there are two different kinds on the
front so will buy two new ones and see how it goes then. So thank you all for your suggestions.

 

[t-tony]

Let's hope that you have identified the main problem Stewart. Tell us how you fare with new front tyres. All the best.