Chevy 2500 HD moved from 245 tires to 265

[diandtom]

Has anyone gone up one tire size on their Chevy 2500 HD Diesel. I did last Thursday and have not towed the fiver yet. It seems according to my GPS the speedometer is two to three miles slower. The tires are a little over 2 inches higher, which may be a problem. The fiver was level when towing before the tire change. I did drive it today about thirty miles and the ride is much better than with the old tires. I am taking the fiver in this week for service, so let you know more after I tow it.
Tom

[diandtom]

Has anyone gone up one tire size on their Chevy 2500 HD Diesel. I did last Thursday and have not towed the fiver yet. It seems according to my GPS the speedometer is two to three miles slower. The tires are a little over 2 inches higher, which may be a problem. The fiver was level when towing before the tire change. I did drive it today about thirty miles and the ride is much better than with the old tires. I am taking the fiver in this week for service, so let you know more after I tow it.
Tom

[lucas874]

Do you contribute the better ride quality to the new tire size, quality or tread design?

[diandtom]

The tires that came on the truck were Bridgestones and were almost worn out at 24,000 miles. The new tires are Michliens XPS A/T. I always have got at least 40,000 out of radial tires.

[Grandpaw]

I have been running the 265s on my rig for 3 years now, with no problems. the stock speedometer went from 2mph fast to 1 mph slow
with the tire size increase.

[450Donn]

There will be a slight change in final drive ratio. Depending on how loaded you are it might make some difference.

[diandtom]

I just got back from towing the fiver to be serviced and taking the truck to the dealer. It cost $85.00 to calibrate the speedometer. I cannot tell a difference in how the truck tows the fiver. I was a little worried about the rig not being level but it is just fine. I could not drop the hitch anymore as all I have it 6 1/2 clearance from the top of the bed to the trailer. When I get my taxes finished and if there is any money left we are going to Mississippi the end of March. O Yea the price of fuel today went from $3.59 to $3.69 JUST WONDERFUL

[MO _ Jack]

Do you remember how much side rail clearence you had with the old tires? I am thinking of going "up" with my next set of tires but the side rail clearence may be a issue. I can program the speed issue with my hyperchip.

Jack

[jwb187]

I replaced my original equipment tires 245's with 265's over a year ago and can really tell no difference in towing. The reason I changed was mainly cosmetic as I thought the 245's looked too small and showed too much wheel well on my truck. I have a garmin gps and my speedometer is off 1 mile low. I'm sure there must be a reason why GM puts those dinky tires on 2500hd's but I don't know what it is...jwb.

[Robbins]

I have replaced the 245's with 265's on my last 3 trucks. Aired up to 80psi, the truck handles my 5er much better and gives me a better ride. My speedo was off about 2mph @ 60. I can't tell any difference in towing in the hills or the flats for that matter. They will also raise your GVWR by 740lbs on rear axle.
The only difference between the 2500HD and the 3500 is tires any how, and already have the same GVWR as it is.
Here's proof:
Silverado Specs
Check this out, it makes for very interesting comparisons

[RustyJC]

To be accurate, changing the tires has no effect whatsoever on the GVWR shown on the driver's door jamb tag. Only the manufacturer or an authorized modifier can change the vehicle's ratings.

Rusty

[diandtom]

Mo Jack the clearance between the side rail is the same as I did not drop the hitch any lower.
They called the other day tell me my fiver was ready and I am picking it up Tuesday. Yesterday diesel went up again to $3.89 at most places. There use to be a place where I could buy diesel a little cheaper than the other stations but not anymore. They are now in lock step with the others. I just got back from picking up the Arctic Fox in Washington, N.C.. It has been up there the last week for wheel bearing packed and brakes adjustment. It is something I have done every year. The RV dealer is about 45 miles away and after I got out of town where there are no stop light. I reset the DIC (I think that what it called) and running between 55-60 MPH I got 10.3 on the way back home. I checked several times and it never got into 6 gear ran in fifth all the way. I have to get above 60 mph for sixth gear.

[Robbins]

Rusty:
Calif. hwy patrol has told me that I have legally boosted my weight rating. They will read the sticker on the door, and also take into account the weight rating on the tires.
Take a look at this site and tell me what is the difference between a 2500HD and a 3500.
Silverado specs

[RustyJC]

Please read my statement again. We're talking about two different subjects. State weights and measures enforcement generally is concerned with axle loading as it relates to bridge and road damage as well as (in many states) revenue generation tied to the vehicle being registered for the weight it is carrying/towing. Using your example, I could put a Rickson 19.5" conversion kit on a Ford Ranger and, with each tire rated for 6,000 lbs, have a Ford Ranger with a 24,000 lb total axle weight rating insofar as the weights and measures enforcers are concerned.

That's an entirely different subject than the manufacturer's ratings for what the vehicle can weigh, carry or tow.

Rusty