tracking

[asifxxxx]

Hi,

With all the wet weather we're having, I've gone through loads of puddles (some shallow, some deep) on the road sometimes faster than I should.

I'm not doing damage to the car am I? Will tracking be affected?
Even with traction control on the 2003 A4?

Cheers.

[onzarob]

I wouldn't advise going through puddles too fast due to aqua planeing, which can seriuosly damage yor car....ie causing you to crash!!!!

Tracking won't be affected by water, potholes can cause more issues here.

Rob:D

[asifxxxx]

You're totally right!! I thought I noticed the steering slightly pulling to one side and thought damn those bloody puddles, they're everywhere! :mad:

Surely the traction control is supposed to help avoid tracking problems in that it distributes power differentially to the wheels? e.g. if going through a deep puddle at speed, the wheel taking the impact will have its power increased to counteract the force of the water? Or am I talking nonsense?!

Cheers.

[onzarob]

Tracking is due to steering not traction. basicall you hit the water it grabs the wheel and pulls it in. If you hit it hard enough you will spin!!!

The traction control, controls power delivery to normal road surface wet or dry. It still requires the driver to make judgemnts as it can only make slight adjustments to traction.

Rob

[tony_anon]

Ok, I get it now. Do you think when the water grabs the wheel and pulls it in, the tracking will be affected? I'm sure there's a slight change since I hit a deepish puddle. Car is pulling slightly to the right with the steering wheel dead centre.

Maybe I should pop into the local garage and get the tracking checked?

Cheers.

[onzarob]

Hitting water can be as hard as hiting a pot hole, so yes your tracking may now be out, get it checked.

Happy motoring.

Rob:D

[asifxxxx]

Got the trakcing checked. Left wheel was spot on, right wheel was out by 2 units. Garage said it was perfectly set, only the 2 units out, so no need to alter it. I told them the steering wheel is slightly to the left when going straight but when I centre the steering wheel, the car moves slightly to the right! They said its not the tracking.

Can the steering wheel be set to the centre position using the steering lock facility i.e. which allows you to change steering wheel height and towards you/away from you position?

[onzarob]

Ok, I think I know what going on here.

I'll explain what pulling to the left/right means it when you drive straight (Not steering wheel straight, but car is going in a straight line) if you lhold the steering wheel loose in your hands the car then starts to move to the left/right without any driver input. that is pulling and can be due to the tracking.

If you hold the steering wheel straight and the car move to the left/right then the steering is not centred correctly, this can be due to poor adjustment of the tracking,but not due to the tracking being out. If this is the case then you either remove the steering wheel (You can't use the console adjustment) and centre it or you get the garage to adjust the tracking, after setting the steering wheel to centre. The garage should be aware of this.

Finally tracking is the road wheels alignment to each other, which needs to be almost parrallel with the front edge in by 1 or 2 degrees, called toe in. like the diagram below but not so exaggerated



Hope that helps

Rob:D

[asifxxxx]

Totally get it now, many thanks for that explanation!! (and pic!).

The front edge in the right wheel was in by about 2 degrees but the left wheel was at 0 i.e. not towed in by the same amount as the other wheel.

So when I get the garage to adjust the tracking, after setting the steering wheel to the centre, should they set both wheels to be the same i.e. about 2 degrees toeing in?

[onzarob]

Glad you like the diagram, worth a thousand words and all that!!!

The toe in figures for a standard supspesion A4 are 1/6 of a degree +/- 0.1 of a degree. But the garage should have the figures. If yours is 2 degrees one side and 0 the other the when the car is running straight they will both be 1 degree! But the steering wheel will be out slighlty.

Now to adjust this there is a nut on each side of the steering rack, these are call track rods,each side needs to be adjusted whilst the steering wheel is straight and all should be great.

Now one more complication, there are two types of wheel alignment tool, 2 wheel and 4 wheel . 2 wheel is obvious as it takes care of the front 2. 4 wheel is when they also take into consideration the rear wheels, this makes sure the car is running true by taking measurments to the rear wheels. Somes garage have this setup as it gives a more accurate setup. I had this done on my golf at a national tyre fitters and they did an excellent job.

I hope thats enough info for now. I suggest you watch as they do it and it will become clear and you can see that its done properly.

It great to get the basics right first before getting stuck into the extra complexities of modern cars. By the way the toe in helps the steering centre, along with camber and castor, but thats another diagram:biglaugh:

Rob:D

[tony_anon]

Rob,

Daft question! : Do you need to get the tracking done every time you change a front tyre?! The guy at the national tyre place said you only have to balance the wheels not re-track.

There are signs of erosion on the outer rims of the tyres which suggests toeing out? I'm surprised as the wheels are 1 degree and well within tolerance (albeit with the steering wheel still not quite central, poor adjustment rather than tracking being out as you said before).

I've had a service and brake fluid change done recently and when I brake sharply, the steering wheel sometimes pulls to the left. I'm surprised if the garage didnt notice any brake discs or pads wearing down.

He also said the tyre were cheap! Wait till they run down and then look at the tracking when fitting new tyres?

Any suggestions for a good brand of tyres for a TDI A4?

Cheers.

[RickT]

no you dont have to get the tracking sorting ever time you put new tyres on... just rebalance..

my tracking is perfect and my tyres showed wear on the outer edges first.. Check what PSI you are running at...

I was always runing at 32PSi... but now im running at 35-36PSI MAX.

In regards to tyres... you get what you pay for

im not sure if you mean the tyre on your car is cheap or the tyres for the car are cheap??

The tyres are not too bad... you can get a decent pair for about £150. however theres loads of budget tyres out there for £50.00 each. you get what you pay for... ie budget i got about 13K miles... Dunlop SP130 i got 20k from...

Cheers

RickT

[onzarob]

That is right you don't need your tracking check each time, unless you have uneven tyre wear. the outside edge wearing can also be down to driving style (going fast round roundabour tend to scrob the outside edge quickly!!)or inflation. I would expect both ouside and inside edge to be warn if the tyres have been run at too low a pressure. The rcommended pressure for 16in wheels is 32 front and back. Not sure what it is for 15in wheels. But its wrtten on the inside of the petrol flap.

The garage have suggested right about adjusting once new tyre are on as once they have been worn down incorrectly, they tend to carry on that way!

with the vearing to the left ocasionally its not going to be an obvoios thing. Could be a brake pipe starting to fail or a calipers not having even pressure on both sides. you wouldn't notice that from changing the fliud if its intermitant. I did notice on my service records that the calipers need cleeaning anf free to even them up. so maybe the need a look at. Hard to tell on a forum ;o(

Tyre choice is mindfield but cheep does have it downfalls in that they don't last as long and the handling can be a bit sketchy. go for a brand name at a price oyu can aford.


Cheers

Rob

[RickT]

one other thing... worse case senerio.... if you have not had the car from new... maybe its been kerbbed heavey or hit a big pot hole which has phyiscal bent the suspension leg or swingarm... however this would be picked up in the tracking as the guys who are doing it would not noticed untill they have put the tracking to the max limit and still cant get it true..


also you state the steering wheel is not center?? this can be a few reasons...

1- when the tracking was last done.. the streering wheel was not checked and it was off center ie lets say 5 degrees to the left... the guys doing the tracking didnt realise and centered the wheels up perfect by adjusting both sides to get the wheels to the cetner.. hence the steering wheel being off center..

2- i know that theres a few roads near me with a extreme camber and mine pulls to the left on these roads every time... to start with you think what going on as you are steering out of it to keep center...

also another place is the first lane on any motorway... due to the HGV's creating channels due to the weight over time.. this creates you having to push that little harder to get out of the channels..

Cheers

RickT

[tony_anon]

Hi,

Many thanks for the posts. My current tyres are 205/55R/16 which according to the info on the inside of the drivers door should be 30 psi for light loads (or 2-3 people). The tyre bloke said they should be 30 psi also. The tyres on the car are cheap: Rear tyres are "Debica", the front are "Hankook". Never heard of them! I guess tyres should be changed in pairs? The tyre place was offering £150 for a pair of Pirellis. No need to change the rears?

The car was recently serviced. Surely they would've noticed anything funny with the brake calipers?

I think they probably didn't realise about adjusting the steering wheel while they were doing the tracking. If they took the wheels off e.g. to look at the brakes etc, they mightve retracked?

Do you need to take the wheels off to change the brake fluid? Again need retracking?

With the steering wheel straight, the car seems to be going UP the camber!

I'll wait till the tyres run down and start again from scratch!

Cheers.

[onzarob]

The tracking is no effected by changeing the wheels, as the steering rack is connected to the hubs they connect to.

The wheels do come of to change the brake flid and they need to use the bleed screw on each caliper to purge the fulid trough the brake line to the brake caliper.

when you say steering wheel staright it goes up the camber, I think this is because you have the wheel staright rather than when the car is running straight.

I do think the bestthing to so is wait until yourtyres are run down then get the wheel centred and tracking done on the next change of tyres.

Sounds to me that the car is running fine, just let down by poorly worn tyres due to poor tracking thta been corrected.

Rob:D