Will I loose mileage going to 265/75/16's ?

the three tires im looking at are,

Michelin LTX M/S (http://www.tirerack.com/tires/tires.jsp?tireMake=Michelin&tireModel=LTX+M%2FS&partnum=675R6LTXOWL10&vehicleSearch=false&fromCompare1=yes&place=17)
Bridgestone Dueler A/T Revo (http://www.tirerack.com/tires/tires.jsp?tireMake=Bridgestone&tireModel=Dueler+A%2FT+Revo&partnum=675R6ATREVOWL10&vehicleSearch=false&fromCompare1=yes&place=22)
Goodyear Wrangler SilentArmor (http://www.tirerack.com/tires/tires.jsp?tireMake=Goodyear&tireModel=Wrangler+SilentArmor&partnum=675R6WSAOWLV3&vehicleSearch=false&fromCompare1=yes&place=26)

I dont go off road.
I do pull a 24' enclosed car trailer that is 7,500lbs. to 8,000lbs. loaded.

whats your opinions?

You will possibly lose a fraction of an mpg due to the increased rolling resistance, but that will offset somewhat by the increased diameter.

I found it to be about a wash went to 265s from the stock 245s.

Don't know about mileage, but if that chevelle is yours :)

!! NICE RIDE !!

I have seen and heard that the Silent Armours will lose the most mileage but it is a really good tire. I run 265s in the winter months and I lost about .2-.5 miles per gallon depending on how I drive.

I didn't notice a difference. I went Mich LTX M/S.

Silent armor for 22k milage & very happy w/ wear. lost of milage for the roll ressiatance???

I've been running a set of GoodYear Wrangler Silent Armor LT265/75R-16E for a little over 10,500 miles and I am extremely satisfied with them. Once I adjusted my manual calculations for the larger tire size, I have not noticed any loss in fuel economy due to the tires.

As far a tire life is concerned, I am very happy also. These tires had 16/32'' of tread when new. So far, they have worn down by 2/32'' in 10,500+ miles. This gives me a projected life of more than 68,000 miles if I run them down to 3/32''.

I went with the Michelin LTX M/S and it stayed the same and the speedo in closer to accurate

I went with the Michelin LTX M/S and it stayed the same and the speedo in closer to accurate

Same here.
Any mileage "loss" can be attributed to the fact that with the stock 245's your speedo is in the neighborhood of 1.5-2mph high. The 265's put it right at or near dead on when compared to a GPS.

So are you saying we are not getting correct numbers when we calculate by hand with the stock tires but we would if we went to 265's? I would like to know if anyone who changed to 265's pull a 5th wheel and if they could tell a difference with the stock rims. One of the main reasons I bought a diesel was for better mpg's and I don't want to go down in mpg's with the increase in fuel prices. I still can't decide if I should stay with 245's or go to 265's. What about 235 85's?

I changed to 265 on stock wheels and pull a 5er.
I did notice a little more "side to side" roll the first time I towed,but now its fine.
I do not regret going w/ the 265. They also look better.

I have run the Michelin LTX M+S and the A/T as well. They both have done very well for me. The M+S had over 65K on them when I sold the truck and they still had tread on them. The A/T's are wearing very well as well, but don't have the miles on them. About 20K. They are a little noisier on the road however, so I would recommend the M+S's

Get some quality 265's and don't look back. I run Toyo AT's myself and mileage is fine.

I went from 19 mpg to somewhere around 17.5 to 18 mpg. I also went with 17x8 rims which are heavier. At 60 on the speedometer I was running 59 and now 62.

I just got my Pro Comp 7105 wheels--17 x 8, with Michelin LTX AT-2's--265 70 17E on yesterday and they are absolutely great. I haven't towed with them yet, but I may take it for a spin tomorrow. My speedometer with the stock 245's was dead on (< 1/2 mile off every 100 miles traveled) when checked with my gps. Checked the new set-up today with my gps. For every 50 miles traveled on the odometer actual on the gps is 52.6. So with the 265's mine is about 5% slow. That was variable speed driving conditions. If you are going with 265 tires it would be wise to go with wider rims--the stock rims are not recommended due to the sidewall not functioning as it was designed to do. Makes for a more stable ride.

i just picked up a new set of 265 goodyear sileny armors and so far i like them alot. as for mpg i did notcie a little drop almost 1mpg but with any bigger tire you will have some power, and mpg lost. i drive down alot of muddy and snow filled trails but i also do alot of highway also to work about 100 miles a day so i need an aggresive a/t tire not m/t. if you dont go offroad at all im sure there are better tires for your needs but for what i do im happy with the wranglers. hope this helps

I lost about 3-4 mpg when I went from 245's to 285's but my speedo is still off so with that thrown in its more like a 2-3 mpg loss.

I have 285 Silent Armor's and they are nice, but I lost a lot of MPG's I'm averaging 12-13mpg in town unloaded and it's hard to get 17MPG on the freeway with them...

I used to be in the 14-15range in town and 19-20 in the freeway...

They are nice tires, but I would not go with a 285 again... I'd stick with a 265 for sure.

I went from 19 mpg to somewhere around 17.5 to 18 mpg. I also went with 17x8 rims which are heavier. At 60 on the speedometer I was running 59 and now 62.

Your speedo should have gone the other direction. Larger tires will cause your speedo to show slower than you’re actually going. Theoretically there is about a 3.8% difference when you look at the revs per mile on a 245 vs. a 265. That difference would almost equate for your difference in mpg. So, they aren't affecting you mileage much at all.

thanks for the help so far. as of right now im leaning towards the Michelin LTX M/S

I switched mine out to the ms right away when i bought it. I propably have over 200k on the ms's. Lasted @ 70k each set. Great highway tires (wouldn't buy anything else for the highway) but don't plan on getting off road without a rope. I spent the better part of a day getting pulled around this last spring where the other trucks went where they wanted. A valance, a few small trees, a fence and a post later I was home free. I was reminded a week ago on a jobsite why the ms's should stay on the road (good thing I had a rope and it was our jobsite with a 644 loader.

I just put michelin ltx m/s on today...went with the 265 from the 285 I had before. Waaaayyyyy smoother tire and much easier to turn the steering wheel in slow parking lot situations than the 285's. The truck definitely seems to like them better and doesn't wander in the ruts of the road anymore. Truck feels a lot more stable. I'm sure the 285's would have felt better if they weren't stuffed on the stock wheels but I'm happy with the new tires and they fit much better.

[quote=Duratime;2108492]Your speedo should have gone the other direction. Larger tires will cause your speedo to show slower than you’re actually going.

When my speedometer showed 60 mph the gps showed 59 mph with 245's. The gps showed 62 mph with 265's and the cruise set at 60 mph.

[quote=Duratime;2108492]Your speedo should have gone the other direction. Larger tires will cause your speedo to show slower than you’re actually going.

When my speedometer showed 60 mph the gps showed 59 mph with 245's. The gps showed 62 mph with 265's and the cruise set at 60 mph.

I understand what you are saying but the relationship is the opposite. A larger tire travels more distance with every revolution than a smaller one. Your trucks speedo thinks it has a smaller tire, so it should show a lower speed than you are actually going. Maybe the GPS was running off a bit when you first tried it with the 245's.

bigger tires WILL make your speedo show slower speeds then what you are actually going

Maybe the GPS was running off a bit when you first tried it with the 245's.

My GPS shows the same: 59mph/GPS vs. 60mph/speedo with stock 245/75-16s.

I'm just commenting on the difference of changing to a larger size tire. If you change to a taller tire without recalibrating the speedo or changing the gears, your vehicle's speedo should show a lower speed than that of the smaller tire if traveling at the same actual speed. It's just math. The speedo and gps can be inconstant, this relationship cannot be. Larger tires go further with each revolution than smaller ones; it’s a fact, not an opinion.

My GPS shows the same: 59mph/GPS vs. 60mph/speedo with stock 245/75-16s.
That is exactly what my GPS showed when I was running my stock 245 tires. Speedo was reading 1.69% FAST.

Now with the LT265/75R-16 tires, when my speedometer reads 70 mph, the GPS reads 71.54 mph (Verified with a stop watch - 50.32 sec/1 mile). So my speedometer now reads 2.15% SLOW.

[quote=XF350;2111438]

I understand what you are saying but the relationship is the opposite. A larger tire travels more distance with every revolution than a smaller one. Your trucks speedo thinks it has a smaller tire, so it should show a lower speed than you are actually going. Maybe the GPS was running off a bit when you first tried it with the 245's.
I have not recalibrated the speedometer. So with bigger tires I am going faster than the truck is showing. It thinks I am still at 60 but I am actually at 62. That is 3 mph faster than the 245's with the truck running the same RPM. Larger tires do travel farther that is why it (gps)shows I am going faster with the 265's. It will show a slower speed if you drive a slower speed. If I want to drive 60 then I have to set the cruise at 58. Before it would have been at 61. I think we are meaning the same thing just looking at it different.

XF350, Sorry I misread what you had written. I guess we were arguing the same point.
:)

I dont regret a thing about switching to 265's. Mileage and power losses are barely to not even noticable. DO IT!

i think it should be mandatory for all duramax owners to get 265's or higher when getting new wheels the stock 245's look STUPID on are trucks

i think it should be mandatory for all duramax owners to get 265's or higher when getting new wheels the stock 245's look STUPID on are trucks
Agreed!

With the high fuel prices I wouldn't want to lose one mpg going with 265's.