[HwyStarJoe]

The Durango has 265\60-18's. I need replacements but I don't want to go that wide. The rims measure 8.5".
Can I get away with 245's? I need better snow handling and better fuel mileage... 265's are far too big.

I guess I should say that it's a Limited, which is the only 2006 that came with 18's. The rest were 17's, and were probably a narrower wheel.

[67Rally]

Originally Posted by HwyStarJoe

The Durango has 265\60-18's. I need replacements but I don't want to go that wide. The rims measure 8.5".
Can I get away with 245's? I need better snow handling and better fuel mileage... 265's are far too big.

I guess I should say that it's a Limited, which is the only 2006 that came with 18's. The rest were 17's, and were probably a narrower wheel.

I have a 2012 Grand Cherokee that came with 245/65/17's. I swapped them out for a 265/60/17. Just the opposite of what you're doing, but those two sizes have the exact same diameter.

You'll be fine with a 245 as long as you go up to a 65 series, assuming you want your speedo to be correct. The 8.5" wheel will be fine.

[HwyStarJoe]

Yeah, I guess a correct speedo would be nice, but I don't care.
I'm trying to save money and put a narrower tire on at the same time. This thing is GONE next year... I just need to make it through the Winter.

[DjD]

30.5" tall

235/65 18 would be 30" tall and the tread with would be 1.6" less than your 265/60 18's which are 30.5" tall... You would see a little speedo difference between the 2 sizes and it might equate to just a slight braking improvement with the shorter tire.

I don't know if you'll see a full mile per gal improvement going with a narrower tire but I'd be interested in hearing your results...

[HwyStarJoe]

Thanks Dennis.
Yeah, I know I can't really improve the MPG of this monster Hemi. Not without a big tune-up. That's not gonna happen. I'm just trying to get through the Winter without putting it in a ditch.
It's full-time AWD which helps.

My main concern is a tire that fits these wheels without compromising safety. I think it weighs 6000 plus pounds and rides\handles like an 18-wheeler on roller skates in the snow. I don't want to roll over, or have a tire with a sidewall that can't handle the weight either. If I step up the sidewall size, that's what I'm afraid of.

[67Rally]

Originally Posted by HwyStarJoe

Thanks Dennis.
Yeah, I know I can't really improve the MPG of this monster Hemi. Not without a big tune-up. That's not gonna happen. I'm just trying to get through the Winter without putting it in a ditch.
It's full-time AWD which helps.

My main concern is a tire that fits these wheels without compromising safety. I think it weighs 6000 plus pounds and rides\handles like an 18-wheeler on roller skates in the snow. I don't want to roll over, or have a tire with a sidewall that can't handle the weight either. If I step up the sidewall size, that's what I'm afraid of.

The sidewall isn't going to be any taller with a 245/65/18. It's going to be the exact same height as a 265/60/18, they are both 30.5" tall.

[DjD]

Joe the 235/65 is a half inch shorter than your 265/60 so you actually end up with 1/4" less sidewall with a 65 series because it's a percentage of the width.

[67Rally]

Originally Posted by HwyStarJoe

... I just need to make it through the Winter.

What type of tires are you running?

[HwyStarJoe]

Originally Posted by 67Rally

The sidewall isn't going to be any taller with a 245/65/18. It's going to be the exact same height as a 265/60/18, they are both 30.5" tall.

Alright... I'll look for 245's then.
How are you guys determining the tire height from the size?

They're Dunlops on there now.

[67Rally]

Originally Posted by HwyStarJoe

Alright... I'll look for 245's then.
How are you guys determining the tire height from the size?

They're Dunlops on there now.

The sidewall height is determined by multiplying the width (245mm) by the aspect ratio (.65). This is the distance from the edge of the rim to the edge of the tire expressed in mm. To convert it to inches, you divide it by 25.4.

245x.65 is the same as 265x.60 = 159.25mm (6.27")

The overall height of the tire is 245mmx.65 /25.4 x2 +18. Why the x2? You have to add the sidewall in twice because there is sidewall above and below the rim.

6.27" (sidewall) x 2 = 12.54 + 18" (rim size) = 30.54"

Or to keep it simple, go here and plug in your numbers:
http://rimsntires.com/specs.jsp

[SixtyAte]

Originally Posted by HwyStarJoe

Alright... I'll look for 245's then.
How are you guys determining the tire height from the size?

They're Dunlops on there now.

Joe..try this....


http://www.1010tires.com/tiresizecalculator.asp

Kev

[67Rally]

Originally Posted by HwyStarJoe

They're Dunlops on there now.

What style of Dunlops? Are the all season, all terrain, highway, etc?

I am running Toyo Open Country AT's. They have a rugged look, they're quiet on the highway, handle very well in wet and dry, and work great in the New England snow. I had them on my last SUV as well.

[67Rally]

Also, the reason I keep referring to my Jeep is that the Grand Cherokee and the Durango are siblings. The use the same wheel/tire sizes, same bolt patterns, etc.

[DjD]

Joe go to www.tirerack.com and look on the left for tires by size. Click that and put in a size and then pick a tire from the list and click on the "spec" link... From there you will find all the info you need, height width etc...

[HwyStarJoe]

Right Brent... as long as a 245 will work, I'll just keep them 60-18's. I don't care what kind really. Thanks for the schooling on determining height. It didn't occur to me, I was only concerned with whether the wheel width would need to come into play when shopping for replacements.

And I was wrong on the brand... they're Cooper Discoverer H/T Plus. Same as the factory installed. Lousy tire... doesn't last long at all on a vehicle of this weight.

The wife stepped down (WAY down) to the Liberty, and I got the worn out Durango. She traded my truck for the little Jeep. No more Chevy's in the driveway... FOR NOW! Like I said this behemoth gas-guzzler is gone in the Spring. I'd keep it because it's a fully loaded Limited. It took me two weeks to find and figure out all the damn buttons and crap. 6 years she drove it and I never knew the pedals adjusted and it had fog lights! LOL! But it's just too damn heavy and drinks gas. If it was a GM, I'd pull this motor and trans for my Camaro because it's 370 ft\lbs of torque! It's got two speeds... balls-to-the wall, and stop (at the gas station).