LT265 vs LT275

[jstaffon]

What would the pros and cons be to changing my tire size on my 2013 GMC 2500HD diesel from an LT265/70R18 to an LT275/70R18? I'm looking at doing this due to cost only. I can get a very good price on the LT275 Goodyear tire. I know it will change my speedometer reading vs actual speed. I'm wondering about any hidden issues I haven't thought of. Thanks in advance!

[transferred]

bucky wrote:
This change would have minimal effect, but remember to have the truck reflashed if you have a bigger change in size.
A bigger change will have an impact on shifting and fueling. Most tuners can correct tire size even on a stock tune.
Be aware that at least for GM and Ram the dealer can only reflash to a factory size offered on your truck, forcing you to a tuner.

No, he does NOT need a reflash after increasing the diameter of his tires by a half inch.
A two, three or four inch jump, it may be a good idea.

[bucky]

This change would have minimal effect, but remember to have the truck reflashed if you have a bigger change in size.
A bigger change will have an impact on shifting and fueling. Most tuners can correct tire size even on a stock tune.
Be aware that at least for GM and Ram the dealer can only reflash to a factory size offered on your truck, forcing you to a tuner.

[2naEagle]

https://tiresize.com/comparison/

Tire Size Comparison

[JustLabs]

Greene728 wrote:
I myself doubt you'll see any changes at all. Especially with the Dmax.

He won't notice any difference. I replaced the junk OEM 265/70/18 Goodyears on my 2500HD with 275/70/18s shortly after I bought it.

At the time, there were exactly two different tires in the OEM 265 size to choose from. I went 275s to open up the tire choices.

[ChooChooMan74]

I did something similar to you in my EcoDiesel, except I went slightly smaller (And smaller wheel diameter). Biggest factor, IMHO, would be going to a more agressive tread pattern.

[Greene728]

I myself doubt you'll see any changes at all. Especially with the Dmax.

[transferred]

Biggest advantage to going bigger could be increased weight capacity depending on the tire.

My 285/70R18 Nitto Terra Grapplers are rated at 3750 lbs each giving me 15k lbs of tire capacity on my SRW 3500.

[jstaffon]

Thanks all for your input! I love this forum!

[old_guy]

you said hidden changes, one is the gear ratio. not much of a change but one any way

[kw_00]

Go with it, I see no issues with going a little bigger in size. if you are able to get a good,deal on them then I would!

[bguy]

Go for it. It would be a greater impact to change to 75 series and stay at 265. Depending on the actual tire manufacturer the differences may be greater or less than the numerical comparisons tell you.
The wind will have a greater difference on your fuel economy.

[Grit_dog]

New tread or aggressive tread will have more of an effect on mpg than the slight increase in diameter. Depending on the vehicle, changing tire diameter could overall increase or decrease mpg a little.
If it fits, which I'm sure it will, here are no detrimental effects of running a slightly larger tire.

[IdaD]

jstaffon wrote:
Did you notice any change in MPG by running a larger tire?

Yeah but it was marginal, and it was a V6 SUV and was a much bigger bump up in size. I doubt you'd notice any difference with the Dmax with mileage, and certainly not in performance.

[lc0338]

only about 0.55" larger in diameter. probably will not notice a change

[goducks10]

My guess is you'll notice no change. The two are only 1/2" different. That equates to 1/4" on the ground. That's no different than driving a brand new tire and one that's worn out.