Fortunately the answer is fairly straightforward for once. Car tyres across the board tend to have a tread depth of 8mm.

4WD tyres normally have between 8mm and 14mm depending on the type/application.

The more tread that your tyres have the less chance you will aquaplane. You can read our article on how NOT to aquaplane for more information.

If you are selling a second hand set of tyres with this information you can now measure the tread that is remaining and accurately state how close to new they really are!

Here are a few things that you can check.

1- Stud pattern
The first thing you need to check is does the stud pattern fit. If your car has 5 studs and the wheels have 4 then obviously you are going to have a problem.

I found a fairly decent stud pattern reference online, you will need to scroll down to find your vehicle.

2 – Overall diameter with the tyre
You need to make sure that once you have your new rims and the tyres on them, that the overall rolling diameter is similar to what your car originally is fitted with, otherwise you could encounter a myriad of issues. (e.g wrong gear ratio, tyres rubbing on guards etc)

3 – Offset
The offset of wheels is also important. The offset of a wheel is described as the distance from the wheels hub mounting surface through to the centreline of the wheel.

This is often the “unconsidered” dimension, however it’s a very important one. If the offset is too much different from the original the whole handling of the vehicle can be adversely affected.

If you want to measure the offset of your wheels this is how it’s done.

• Measure the overall width of your wheel (don’t take the numbers on it, as that is flange to flange)
• Divide this value by 2 – this gives you the centerline of the wheel
• Next measure from the mounting surface of your hub to the inboard flange, this is what is called your back spacing
• Subtract your centreline from your back spacing and that is your offset

Remember if in doubt, best not to do it, you don’t want to be stuck with a set of rims that not only doesn’t fit your car, but you have no idea of what car they will fit.

For each tyre..

Tyre tread depth – do you have enough tread to get you through the next 6 months?

Condition – make sure there are no cracks or nails, screws etc in the tyres

Pressure – Ensure your tyre pressures are correct, if you are not sure what to pump them up to refer to our previous article regarding tyre pressures – we spell it out.

Alignment and Balance – Does your car have the shakes or jitters? Does it pull to one side or perhaps the tyres are starting to wear in an uneven manner? Head along to your local tyre shop and get it checked out.

Remember the two most important things on cars are tyres and brakes, if either of those are in dodgy condition you may not stop when you really need to in a hurry!

In fact this picture shows exactly the type of string plug used.

Roll forward a couple of years though and doubts started to surface around the safety of using such a way to fix a tyre. For one thing because the tyre was not even removed from the rim, damage could have occurred internally to the tyre which would not be known about. This damage could cause the tyre to prematurely fail, or be unsafe at high speeds when temperatures were higher than normal. In short the safety of the tyre was now in an unknown state.

Is it legal to plug a tyre? Well it’s hard to find specific text to state that however when checking on the VTNZ website they had the following to say.

Many garages sell ‘string repair’ kits or sealants as a quick-fix solution for tyre punctures. Use these as temporary measures only, to get home or to a repair service. Drive slowly and for a short distance

Remember your safety is worth a lot more than saving a few bucks, so get your tyres fixed properly by an approved repairer.

Note this is for car tyres and small 4WD Tyres only.

I noticed one of our clients used a company called shipmytrade.co.nz which appear to specialize in delivery options for trademe traders. Could be worth a look as well if you are thinking of shipping small goods around the place.

We are interested in your feedback as to which delivery options you prefer so please share.

This appears to be a much debated subject with two sides to the argument. Tyreshops charge extra to do this in most cases and it is an additional revenue earning service for them.

The Tyre store will inform you of the following reasons for doing this.

• You will get better fuel economy, because Nitrogen contains larger molecules than air the tyre pressure in your tyres will remain more constant.
• You will get a longer Tyre life because the Tyres will run at a lower pressure.
• Your wheel rims are less likely to rust, as there is less moisture in Nitrogen than what is in Air.

There are plenty of arguments as to whether or not these claims add up or not, so we would like to share with you our opinion, which is based on the research we have done, as well as the outcomes of the experiment undertaken by Consumer Reports in the US.

Our research showed that although Nitrogen does slightly slow down the pressure loss from tyres, the difference is only slight. Consumer reports tested 31 pairs of Tyres over one year. Those filled with air lost an average of 3.5 psi, the Nitrogen ones lost 2.2 psi.

We also found out to our own surprise that compressed air is around 75 – 78% Nitrogen anyway. Your tyres already have nearly 80% Nitrogen in them for free from the local gas station!

In some applications e.g Heavy Trucks, Formula One racing etc the small percentages can help. However we would suggest that as a car motorist unless you feel like watching your hard earned cash disappear in a puff of hot air that you keep your money in your wallet and instead check your tyre pressures REGULARLY.

Our research shows that the pricing of nitrogen inflation can vary from $5 to $12 per tyre.

Often you will see comments about people getting their tyres filled with Nitrogen and suddenly noticing better mileage and handling etc, however we would like to suggest that the same things can be achieved just by inflating them to the correct pressure!!

Source: Consumer Reports US

Firstly lets explain exactly what wheel balancing is and isn’t and then how much you should be expecting to pay for it.

Wheel balance is the art of measuring a wheel and tyre assemblys heavy spot and counter acting them with small lead weights.

If your wheels/tyres are out of balance you will likely get a vibration at speed ( 80km + ). The steering wheel may shake if its a front tyre, the whole car normally shakes if it is a rear tyre. A good tyre fitter will ask you what your symptoms are before ripping in and just balancing your wheels.

Wheels are balanced when new tyres are fitted, the wheel is spun up on a wheel balancing machine and the tyre fitter then bangs on small lead weights and then rechecks, until it spins up perfectly.

Things to watch out for..

• Too much weight – a good tyre would normally only need a smallish weight, if the fitter is attaching enough weights to sink a small boat, it would be a good idea to ask why!
• Weights should be all in one place on each side of the wheel. i.e you would not have weights opposite each other as that is counter productive.
• If you get a shake or wobble at slow speeds, you may have a buckled rim or out of round tyre. Occasionally the tyre may even be seperating which is where the tread and casing start warping out of shape

For pricing here are some examples we found from calling around.

Standard car/alloy wheel balance averaged out at around $12 to $13 per tyre.

RV/Light truck wheel balance $16 per tyre

One place offered us a special high precision wheel balance for $19 a tyre, this involved a back cone and studs at the front of the wheel, to spin it up much like on the actual vehicle itself. This is the kind of thing you could look at doing if you had a slight annoying shimmer or vibration that a basic wheel balance didn’t rectify.

Well there you have it, if you would like to share your experiences good or bad to do with getting your wheels balanced please share with us!

For those that want an explanation for this here it is.

Oversteer

Oversteer is when a vehicle is cornering and the rear tyres run a higher slip angle than the front tyres. This means the rear can spin around which is a very dangerous situation for a driver to attempt to control. Oversteer can be caused by having tyres with the highest level of adhesion on the front of the car. For safety reasons this should not happen!

Understeer

Understeer is when the front tyres have a higher slip angle that the rear tyres. Interestingly most car manufacturers have a certain amount of this built into the dynamics of their vehicles as this is safer than Oversteer. Understeer can be caused by having the tyres with the greatest amount of traction on the rear of the vehicle.

The Verdict!
So here it is again just so you don’t forget. New tyres on the BACK of the vehicle for MAXIMUM safety. Often people think that the new tyres need to go on the front as they are less likely to blow out, however this is a false concern.

Please join us – we welcome you!

The Tyre Forum

We decided to find out how much one could expect to pay for a basic 4 Wheel Alignment on a Toyota Corolla from a couple of places in Auckland.

Firestone
Firestone do not have a price listed on their website so we had to get inventive and pick up a telephone. The guy on the phone asked what sort of car it was, and we mentioned it was a Toyota Corolla. He then advised that although normally they charge $85 he could do a full four wheel alignment for us and it would only cost $69

Beaurepaires
On the Beaurepaires website at the time of writing this article they have listed “the average price” of wheel alignments, for cars that is $89, for RV’s its $99.We rang the guys at the local Beaurepaires and they said for a Corolla they could do it for $70.

With that in mind we would definitely recommend ringing around, and who knows if you catch them on a quiet day you may find yourself a bargain.

What exactly do you get for your money?
Here at Tyresforsale.co.nz we think that for the price of a wheel alignment you should get your car adjusted to its manufacturers specificiations, and also your Tyre pressures checked and adjusted.

Wheel alignment machines need calibrating on a regular basis so make sure the Tyre Store you get your pride and joy aligned at is the type of place that calibrates their wheel alignment machine.

Should I get my wheels balanced as well?
If you are experiencing any vibration symptoms ( especially at higher speeds ), a wheel alignment is not going to fix that, you may need a balance as well. If your tyres have just been fitted however they should already be balanced and getting your alignment checked will help ensure you get the maximum value out of your tyres.

How do I know my car has been aligned correctly? Our belief is that the following should be expectations after getting your vehicle aligned.

A straight steering wheel - No wheel alignment technician with any kind of pride will let a car go out after a wheel alignment with a crooked steering wheel.

Even Tyre Wear - Although there are exceptions as long as your tyres are aligned to your manufacturers specifications, the tyres are rotated regularly and the car is driven in a decent manner your should get reasonably even tyre wear.

Straight Driving - On New Zealand Roads your car should drive fairly straight or have a slight tendency to veer to the left ( our roads are sloped to the left ), it is very dangerous to have a car that has any tendency to pull to the right as that means if you lose concentration you can veer into oncoming traffic! Often a tyre can cause a slight pull to one side or the other, and the simple fact of changing them from side to side can negate the issue. Don’t expect tyres that are worn on one side, to drive in a straight line however!

If you have any questions, or comments/stories to share about getting a wheel alignment done on your vehicle, or recommendations as to where our visitors could go then please share with us.