I was reading another thread about wheels and tires and decided to put this one together. I worked in a tire shop during college and learned quite a bit. There are some simple things about tires that you need to know. It is really easy to take them for granted, but with a good set of stock sized tires running in the neighborhood of $1K (for 5th and 6th gens), you need to do as much as possible to maximize their life.

1. You get what you pay for. There is a reason that some tires are cheap. Different tires have different rubber compounds and different materials used in the belts and sidewalls. The more expensive a tire is doesn't necessarily mean that it will last longer; it may be a performance tire, which actually has a very short mileage guarantee (due to the soft rubber compound used for more traction). Also don't complain when your tires wear out when you bought the cheapest one they had.

2. There are 4 speed ratings for tires S, HR, VR, and ZR, in order from lowest to highest. The higher the speed rating, the stiffer the sidewall. You won't see an "S" rated 40 series tire, it will usually be a VR or ZR, due to how strong the tiny sidewall needs to be to hold up the car. Typically the higher the speed rating the fewer miles the tire will last. You will find an "S" rated tire on Sentras, "ZR" tires on a 350Z. With proper care, you can get 80K miles out of a "S" rated tire, you will be lucky to get 50K on a "VR" or "ZR" tire.

3. ROTATE YOUR TIRES!!!! I can't stress this one enough. If you don't regularly rotate your tires, they won't last. If you don't, or if it has been 7-10K miles since your last rotation they will start to wear laterally on your non-drive tires. This is most prevalent on wider tires, like truck or performance tires. If you haven't had this done, go out to your car and check the back tires, along the inside edge. If you feel the tread you will notice that each tread block is "cupped." The leading edge of the tread block is lower than the rear. You can't undo this damage; it will cause excessive road noise and eventually vibration. You can minimize your damage by regularly rotating your tires from now on. Some people have them rotated every time their oil is changed (3K miles), I do mine at 5K. Either will work as long as it is a regular interval not exceeding 6K miles.

4. Tire balancing is very important. This can cause your steering wheel to gently move side to side at certain speeds (see "The shimmy thread") or cause the rear of the car to vibrate. Have this done when you get your tires installed and ask to watch them do it, make sure it reads 0.00 on both sides before they take it off. Only a lazy tire tech will do this improperly. There are two main ways to balance a tire. Dynamic balancing places weights on the inside and outside of the tire. It balances the wheel and tire horizontally and vertically. Static balancing is where there are only weights on the inside of the tire and it only balances the vertical plane. If you are getting "the shimmy" make sure your wheel has weights taped to the inside of the wheel near the outside and on the inside lip. Obviously a dynamic balance is better than static. If you have tires with a large lip on the outside, you will not be able to get a dynamic balance unless you want weights hammered or taped to the outside of your wheels. If you have a "lifetime balance," there is no reason not to do it at every tire rotation. But, if you don't, it won't be a problem unless you are getting a vibration.

5. Check your air pressure regularly. You should visually check your tires every day. Sometimes there is a slow leak and it will be hard to notice. As a good rule of thumb, check it once a month or if there is a drastic change in the temperature. If it gets cold outside quickly, your tire pressure will drop considerably. The opposite will happen when it gets hot outside. If your tires are over-inflated or under-inflated, they will wear in the middle or on both edges. I know this doesn't sound right, but the centrifugal force of the wheel spinning pushes the center of the tire out if there isn't enough air inside. If the outside of your tires is wearing (this will usually be one side only) you have an alignment problem. Take it to the shop to have it aligned properly. If your tires have been destroyed, wait until you get new tires to have it aligned, but do it immediately after you get them.

6. God forbid you get a flat tire, but if you do, don't drive on it. Put your spare on and head straight to the nearest tire shop. If they tell you it isn't repairable, ask to see the tire. If the nail (or whatever it is) is in the sidewall or near the edge of the tread, it really isn't repairable. Also if there is a big pile of rubber dust inside the tire, that means you drove on it flat and ruined the tire. Never let someone put a "plug" in your tire. It must be patched from the inside. Plugging can cause more problems that it is worth, even though you can get it done very cheap.

7. Shop around for tires. When you get a quote from a shop, find out what is included. Some include everything in the cost of the tire to make it simpler. This is fine, but just understand that the tires will seem quite a bit more expensive than someone else, until they tack on mounting, balancing, valve, tire disposal fees, and road hazard. Once you find the best price, take it to someone who does price matching and have them beat it. Yes this takes a little work, but can often save you $50- $150.

8. Do you want road hazard? This really is a crapshoot. Who knows if they are going to get a tire destroyed, but if you are spending in the neighborhood of $200 a tire, you don't want a blowout in 3 months and have to buy a new one. These warranties will be more expensive depending on how much your tires cost. My ex-wife's old car had 3 Yokohamas replaced in a matter of months under warranty, but I never had a flat on my truck and the Michelin's lasted 90K miles. Even though they say you get a free tire, you will still have to pay for the mounting, balancing, and a new road hazard warranty if you get it replaced. So if your warranty is $30, it will probably end up costing you $75 for a new tire ($30 for original warranty, $30 for new one, and $15 for installation). Is it worth it to you? You decide, but now you know.

9. Tire siping is a "rip-off." This is a service offered by many tire installers. This is where they cut more grooves in your tire. They say that this causes better wet weather traction and keeps the tire cooler, which makes the tire last longer. If having less rubber on your tires had that much of a positive impact on performance and life of a tire, don't you think the manufacturers would do it when they were made? The more grooves a tire has, the louder they are. Don't pay for this.


All of this is off the top of my head, I will add to it when I think of the stuff I missed. Of course results will vary, and believe what you want. Make your own decision; I am not responsible for your actions

 

I'm going to offer a few revisions. There are more that 4 speed ratings include TR,WR,YR .... the tires construction not the speed rating that is related to sidewall stiffness. In general higher rated performance tires are stiffer. Speed rating indicates the tire withstood that speed for 1/2 hr in testing. Speed rating does not indicate tire life compound does. In general higher speed rated tires use a softer compound. Underinflated tires will wear the outside edges, overinflated tires will wear the center. Rotation is important, however on a front wheel drive car the rear tires should wear flat and even. If your rear tires are wearing unevenly you have a suspension or alignment issue. Cupping is caused by balance or suspension issues... most likely a combo of the two. Static balancing (bubble balance) is done on a fixture that balances the wheel and tire without movement. I have not seen a shop with static balance in 20yrs. Dynamic balance is when it is balanced on a machine that spins the wheel then indicates locations for the weights. Road force balance is step above that with the tires actual weight applied to the road meassured. As for me I work for a Porsche/BMW/VW dealer and I road force every tire I install from a GTI to a 996tt.

One thing you didn't talk about was the tires heat cycle. Every time you drive your car you add a heat cycle to the tires. Every heat cycle the tire gets harder. As the tire gets harder performance goes down and endurance goes up. I look for around 20k from a set of tires, I think 80k tires are stupid and dangerous. Think of the little patches of rubber that connect you to the road, do you really want to skimp on the most important part on your car??

 

Good additions. But rear tires won't wear flat, look it up. As for the balancing, if you get your tires at Sears, Sams, Discount (America's) Tire Company, they still do static balancing. I can't talk about the high end stuff, I worked for Discount, but that has been 10 years.

Most people look to get more than 20K from a set of tires. I would imagine that you probably drive your car pretty hard (could be wrong) but most people will drive theirs at least until 40K unless something happens to them. As long as they perform in rain they should be fine.

I'll openly admit that I shouldn't have kept the tires on my truck that long, most of it was to see how long they would last.

Typically you will only find the 4 main speed ratings, you will need to go looking for the others, but there are a ton more than that.

 

I see alot of VWs with the second set of front tires, rears flat and 6/32s + remain at 40-50k miles. The only unusual wear I see in the rear of our front wheel drive cars is related to damage. Bent axles or twisted mounts cause feathering or camber wear. Poor balance and dead struts cause cupping. Front wheel drive cars with true IRS may have other alignment issues due to design. Solid or twist axle style rears should wear very even.

I do drive hard and go thru 1 to 2 sets of tires a year between the Z and the Max. The last set of tires on the Z went about 2500 miles and 15 track events. It now has "R" compound tires dedicated to the track so I should get 15k out of the street tires I just put on it. The Max has about 12k on the current tires and they are about 3/32nds due to be replaced very shortly. My advise for Z guys with neg camber wear issues is to drive harder to even the wear..lol

 

What I notced is that the heavier the car, the more problems the non drive tires have. That would explain why you may not have seen much of it. I noticed some (just a little) on my Maxima, but from the looks of the tires, they hadn't been rotated in the 15K miles it had on it. If I were to have gone 15K miles in my truck without rotating, the front tires would be totally ruined due to lateral wear.

If you use the words "track event" in the same sentence with your car, I can understand paying attention to the heat cycles and you are going to have tires that are designed to be changed in short intervals. The RSA's as crappy as they are shouldn't have a problem going 40-50K safely for road use. I don't know that I would want to try a track even with them when they are new, but I don't plan on doing that.

Thanks for adding to the thread.

 

I found a mistake!!!!!

My Sentra came stock with "Z" rated tires.

Seriously- good info.

 

I have lifetime balance, rotation, and alignment at Discount Tire Centers. All I need to do is ask them to balance, rotate, and align, correct?

When they originally balanced my tires, they only gave me static balance, 1 strip down the center. They told me only high performance cars do dynamic. What punks.

Anyways, when I go in for my lifetime balance, are they supposed to remove the existing weights? Or do they add on?

Jae

 

cliff notes?

 

My Discount Tire store only uses the "spin" balancer. I would demand it. If they are just checking your balance it is not neccessary to take the weights off. If you tell them you feel a balance problem they will probably take the weights off and re-balance.

 

I had them redo the balance for dynamic. So that's ok now.

As for the rebalance, I see what you're saying, they leave the weights on there and just check. If there is an imbalance, do they take off the existing weights and start from scratch? or just add as necessary to the existing ones?

thanks.

Jae

 

There are tire speed ratings spanning almost the entire alphabet. Lots of them are not in use anymore though.

 

They will usually take off the weights and start from scratch.

 

Their policy is that if they have to add or subtract weight where the weights are already, then just do that. In other words, they are told not not put weights in different places on the wheel. But it all depends on which guy balances your tires. Some people care about what they do and some don't, just like any job.

 

For most of my customers if I'm checking balance, if the roadforce is good and it's calling for something small I may just add the weight. Anything over about 15 grams I'll pull the old weights and start over.

 

Thanx guys. with that knowledge, I feel more confident asking for them to take the old weights off if necessary.
Jae

 

good info fellas.

 

Recently I’ve purchase Pirelli P-Zero Nero M&S and since then car hasn’t drive as good as before. Now it kind of wonders on the road (it almost fills like the steering is over responsive and I’m sure is nothing wrong with my car). Is it due bad balancing or is the tire?