Maxima_Freak13

Guys I need help to figure out what tire width do I need to get my the tire to be flush with the fender or would I be better of getting spacers with 255 tires?

MaximaDrvr

iTrader: (1)

Are you getting new wheels?
You can't just add wider tires to stock wheels, you need spacers to make them flush.
With aftermarket wheels, you can change the width, offset, and tire size to make it all flush.

Maxima_Freak13

Ok reason im asking is cuz I was out of town and the wife was usin the Max and she kept complaining that one tire kept leaking air so I told her go get it checked so when she wen they told her it needed another tire and she bought a used tire but they put a 255/40/19 insted of the 245/40/19 the car has and thats why I was asking

lightonthehill

I gather that you are already making plans to rectify the situation you temporarily have, and you are probably aware of what I am about to say, but perhaps others here may not be aware of this, so I will say it:

Without getting into which tire sizes can or cannot be used on the Maxima, I will simply say that the outer diameter of both tires on the same axle must be the same, otherwise the diameter discrepancy will result in abnormal wear on drive train components, and also the car could perform erratically in emergency situations.

Unless the tread has worn low on a 255/40/19 tire, AND the 245/40/19 tire at the other end of this axle is fairly new, I would not keep this combination other than very temporarily. It seems you are already making plans to address this, which is good.

As info (which you probably already know), the 255/40/19 is close enough to the OEM 245/40/19 that it should be usable on the OEM rims, and might even be fully flush with the fender well opening. Being slightly larger than the OEM tire, it will give a slightly larger road contact footprint, a slightly more solid feel when maneuvering, last slightly longer, and result in your speedometer reading one MPG or so lower than the OEM tires. If doing this, I would carry one pound less than normal in the tires, as the larger tire will not be carrying the full normal weight for which it was designed.

But I ramble. Others here will know exactly what will fit the wheel well opening to perfection. Let us know what you end up with, as there will be others here interested.

MaximaDrvr

iTrader: (1)

Tire size has little to do with flushness to the fender.

NO.

LudaTej

iTrader: (2)

You need to get that 255 out of there ASAP! But to answer your question, if you're looking to go wider than stock than you must also consider that the tire extends in both directions. As in outside towards the fender as well as inside towards suspension/brake components. Approximate equivalents to a 245/40 would be either a 275/35 or a 285/35.

Here are the diameters of the tires
245/40: 678.60 mm
275/35: 675.10 mm (0.52% less than stock)
285/35: 682.10 mm (0.52% greater than stock)

The 275/35 is 30 mm wider than the stock 245/40 so it would stick out 15 mm towards the fender and also 15 mm towards the suspension/brake components. The 285/35 is 40 mm wider than stock and it would stick out 20 mm on both sides.

But I would suggest you avoid all this hassle. Just add spacers with the stock tires and call it a day.

lightonthehill

As for the flushness, you may be right. But the first number of a tire size is the width of the tire. I would think increasing the width of the tire will make a difference as to where the outer sidewall reaches in relation to the fender well. It certainly does on the many cars I have owned.

As to reducing the psi by one pound, you may be right. But from 67 years of driving experience, the first forty-five during which I always switched to larger tires because vehicles were usually 'undertired' back in the 1940s thru the 1980s, I found a few things were absolutes:

If I carried the same psi in the oversized tires that I carried in the OEM tires,

1 - The tread wore out in the center before it did on the edges, because the weight of the vehicle was not enough to allow the oversize tire to run with its intended profile.

2 - The front-to-rear footprint of the tire was very slightly reduced, as the weight of the vehicle was not enough to allow the tire to run with its normal profile. This extended the stopping distance very slightly, and extended the turning grip very slightly.

3 - Carrying the vehicle recommended psi in a tire that is larger than the OEM size for a vehicle tended to increase any tendency for the rear tires to bounce or skip in sharp turns on irregular pavement over OEM tires carrying the same psi. Of course this tendency is exacerbated by the smaller footprint mentioned in #2 above.

Of course nothing is ever absolute or clearcut. The recommended psi for any vehicle is the manufacturer's engineers' compromise between best handling for the car and the most comfortable ride.

This recommended psi works for the average driver, but many drivers are not average. I find 37 psi in front and 35 psi in rear gives me the best control of my car in all situations, and results in my tires wearing evenly between the center of the tread and the edges. I measure tread depth of each groove on each tire every three months in order to make slight adjustments in psi if the tread is not wearing evenly between the center and edges of the tread.

For cars that are driven mostly on freeways and straight roads, 37 psi would result in the center of the tread wearing out before the edges. Every driver is different, and driving situations are different.

Maxima_Freak13

Thanks guys for all the input I havent moved the car at all that much since im almost always on the road and she got her car now but really quick what size spacers should I get I know the Ichiba V2 Hub centric specers but what mm to have them flush with the fender?