[ozarkpreacher]

I did a search and looked thru a great number of threads but still haven't found my answer.

I am going to have to replace my tires soon. I have the stock 265/70R18 tires on now. I have after market 9" wide wheels with factory offset. Also have 2" lift on front. It is a 4X4.

Looking at possibly replacig with either a 285/65-18 or a 275/70-18. Most of my driving is on pavement and I do tow a lot. Usually a 26' travel trailer. Will either of the above sizes rub with my set up? Will I need to have the speedo recalibrated? What about tranny shifting changes? Fuel mileage diff.?

Don't want to do anything to hurt my trucks performance or make the fuel mileage any less. If I need to I can stay with the stock size but there's not much out there in the OEM size to choose from.

Any help appreciated.

 

[ozarkpreacher]

any help at all here would be appreciated.

Thanks

 

[NorCal 4x4]

... I have the stock 265/70R18 tires on now. I have after market 9" wide wheels with factory offset. Also have 2" lift on front. It is a 4X4. ...

Factory offset on the 18x8 rims is +25mm so the backspacing is 5.5". Since you said the offset is factory on your 9" rims ... +25mm of offset gives you 6" of backspacing, so the rim sticks in 1/2" more than factory. Because of this you will rub the steering knuckle with a skinnier tire than someone with factory rims. Also, a wider rim allows the sidewall of any given tire to be a little wider than it would be on a narrower rim, (BFGoodrich spec sheets for their AT and MT tires state 0.2" less for each 1/2" narrower rim).

But a nominal 285mm wide tire is only 10mm, (~2/5"), wider than a 265mm tire, and would only stick out about 1/5" more to each side of your current tires on the same rim. If the stock tires are already on the 9" rims and you have some clearance between the wheel/tire and steering knuckle, think of about 1/5" less clearance.

If your 265s are still on the stock rims, take the 1/5" and and another 1/5" because the wider rim, (still talking about just the inside or back of the rim), then add the 1/2" more of backspacing, and you're at about 0.9" less clearance, than stock wheel/tires.

The other potential rub is at the pinch weld, back of the front wheel well when you turn the steering wheel. Again, just see how much clearance you have now. You will probably be fine with either tire size that you mentioned.

I don't think you can recalibrate the speedometer on a Titan, but there are tire calculators that will tell you how much you're off. The 285 is the same diameter, and the 275 is only 0.6" greater in diameter. Your shifting probably won't be affected until you reach a 34" or greater diameter.

Fuel mileage will be affected a little if you go to a heavier tire, but if I was towing a big load, I would run light truck tires instead of a passenger rated tire.

 

[ozarkpreacher]

thank you NorCal, that is exactly what I wanted to know.

Very much appreciated.