load index
 

the factory nismo tires ADVAN sports have a load index of 98Y. i was thinking about going up to a 255/35/19 tire size up front but i can only find tires with a load index of 96Y......

is this something you guys take into consideration when buying tires?

Load Index Chart - Discount Tire

I really don't. The thing I mostly take into considering when purchasing tires is the compound number (it differs between manufacturers), tread design, and speed rating. Most of the tires that are in the size that we purchase for our cars are going to have a very close load index. Our cars can only have about 500lb payload between to passengers and cargo. I may be off a little but thats what i recall since i don't have owners manual in front of me. Example: I got 22k out of stockers but wanted somthing a little more longer lasting, so I went with the re760. Im no happy with that tire because it is still loud maybe louder than re11's. So my next step might be the falken 452. I had them on one of my other cars and liked them. Just my .02, hope this helps.

the load index for the nismo is higher than whats called out for on the sport..... interesting. maybe its the added down force created?????

I think thats a good idea. But for what its worth, im a bigger guy 260ish and my wife was with me when I went and bought a 600pc tool set at sears, along with her front and rear rotors, pads, and oil$ filter. I am familiar with load in reference to vehicles and performance....seriously the Z was way way WAY over loaded. I took it very easy getting back to my apartment. that was close to 600lbs in payload and you could feel every bump. Maybe your suspension is stiffer which allows for more cargo too? the only thing thats that same between our cars (from factory) is the tires and size of rim? My guess is the springs.

front & rear rims are 1/2" wider and springs are stiffer.

im 205lbs so ill try and stay with what nissan wants as far as a 98Y rated tire.

hey fuct its only 88lbs. Im sure you'll be fine either way. Just noticed also you have/had tien springs, might want to varify with them what your car is capable of with those. Your total gross vehicle weight could be reduced since its not considered a stock load bearing spring.

true.....

over the phone the discount tire guy said he didnt feel comfortable using the lower rated tire. is he being over careful so they arnt liable?

I don't think so, i did a search on my car and it ranges from 96-103 depending on what tire i want to go with. I think it has to do with the sidewall thickness as well as the compound of the tires themselves. I have never had a problem with america's tire co before as far as not wanting to put a tire on your car. I don't think (even though he works there) he knows specifically what he is talking about.

I work at Costco and we are very strict about load ratings. Basically match manufacturer specs or higher. Lower load rating will make you more prone to pot hole wheel damage and blow outs from those pot holes. You think 88lbs isn't a lot? X4 and you're basically 350lbs short of correct support. Not only that but your tires won't wear right as it can only be inflated so much. Over inflate to compensate and now your running the risk of bubbling the sidewalls in potholes or a blowout but a lot of people do run lower load rating tires. To each their own but I'm fine searching for tires that need meet the load rating. The reason load ratings vary is cause a lot of Mercedes, VW and BMW need XL (extra load) tires to properly support the vehicle. This limits their choices but its comes with the vehicle and the extra weight that comes with them. Just my .02

Ok im not arguing with you on these points, im just wanting explanation why it is that when you do a search on tires.com and put your information in on the website that the load ratings are different from one tire to the next as far as load rating goes. Case in point, for stock rim and tire setup on the Z here is a list:Falken 98y front 96y rear, BFG 98y front 96y rear, Yokohama S Drive 94y front 96y rear, Re760 Bridgestone 98y front and 100y rear.

Also, I looked at the OP and researched the load numbers. Again it WON'T matter due to the fact that each tire at 96 is capable of 1565lbs, so x4 and that gives you a total load capacity of 6260. Gross vehicle weight on our car is 3232. max payload on our cars if im not mistaken is around 600lbs? I am kindly stating sir that you are incorrect when referencing passenger car tires to sportscar tires.

As i stated, my .02. Take it or leave. Manufacturer specs is what they are for a reason. If you don't like it, you can find a shop that doesn't care either. Good thing there isn't any extra forced pushed onto the tires when you hit potholes, bumps, dips, or lips in the road that cause extra compression on your tires in quick bursts....... Lucky..... Kinda like saying, a 200 lb man jumping is only landing at 200lbs of force.

Like I said, I'm not trying to argue with you over your statement. SO....there is over a thoustand pounds of force loading the tires when driving this car down the road? Minus potholes and passengers and payload on car? What does the manufacturer reccomend for load rating on our tires?

its on the sticker on the driver side door sill.

I agree, and this type of thread should be a sticky for educational purposes. Easy example: scale reads real high the moment you step on it, then backs down to your real weight.

Motions create extra load on the tires. The debate is really about how much extra and what the safe margin is.

There must be a formula somewhere...