I am buying a 3500 diesel
I have a 2500HD with 285/75-16
the 3500 comes stock with 215/85-16
what do I need to do to put 285/75-16's on the rear?
the front does not look like a problem

Without buying new rims the largest tire that you can run on the 3500 DRW is 235/85R16's. You can run the 235's @ 65 psi without rub issues running unloaded. As soon as you start loading any weight 80 psi is a must. I'm not sure who offers 16 inch rims that have an offset that would allow the 285's to work.

What about wheel spacers?

I looked at wheel spacers but with the rims being hub centric I had concerns with heavy loads an the spacers causing the outside rims to become lug centric. I think you would also have to get spacers that are 2 inches thick if you don't want to cut the stock lug bolts off. What are the torsional forces that get put on the axle, under heavy loads, when the outside rims end up 4 inches further apart.

If money's no object you could look at 19 or 19.5 rims like others have gone to. I stayed with th 16's so that I could use the tires off of the truck on the trailers after they were worn down.

I am buying a 3500 diesel
I have a 2500HD with 285/75-16
the 3500 comes stock with 215/85-16
what do I need to do to put 285/75-16's on the rear?
the front does not look like a problemWHat year are you looking at buying? The 05's come with 265's stock. FYI

WHat year are you looking at buying? The 05's come with 265's stock. FYI

They do? I better go see what I got.

I Have A 05 Chevy Drw And I Have 215's I Wish It Came With 265's

I have 255 85's and before I installed the 2" spacers a tried mounting the tires and there was no way to run them even unloaded and at max psi. The 285's will be even a little wider so forgett it without the 2" spacers. I only tow a 10k boat so not real concerned with the load with the spacers...got my spacers off from ebay quality and price very good.

Only the Single wheel 3500 comes with 265's.

what is the reason for 285s if i can ask. i run 265/75-16 on the front on my dooley and 235/85-16 on the rear. no rub in the rear and the tires are within .10" in overall height. 285 will only get you 3.5% more height (about 1") No spacers needed and it stays in the wheelwells in the back

what is the reason for 285s if i can ask. i run 265/75-16 on the front on my dooley and 235/85-16 on the rear. no rub in the rear and the tires are within .10" in overall height. 285 will only get you 3.5% more height (about 1") No spacers needed and it stays in the wheelwells in the back
Thank You
these were the figures I was looking for

I have seen pictures of somebody on this website that has 2" spacers on the rear and runs 285's. If he shows his face ask him how it works.

chevmeister
Are you running the differnt tire sizes front/back on a 4x4? Even with that small of a difference between front and back circumference, can rip the transfer case out if you happen to hit dry pavement and forget to take it out of 4x4.

weekilty
the upside with going to the 265's on the front is the 3415# capacity vs the 235's capicity of 3042# using load range 'E' tires. I run a goose neck and load it heavy, and have never gotten close to the max front axle max capicity. I guess if you were going to run a slide in camper, you may end up with more weight on the front end. The front axle max on the door on my 04 is 5885 if I remember correctly, so the additional capacity of the 265's is lost.

hi again,

what is the clearance on your rears with a load with 235's and what brand and type of tires are you running. thanks i am looking to do the same. thanks

The tire shop that I use gave me a couple of optioins of tires with firm side walls to reduce the chance of rubbing from excessive flex under heavy loads. I picked Firestone Steeltex's for my truck as I still need them soft enough to grap in the dirt/mud/snow. The Michelins I have run in the past were great on the pavement, but did not allow me to pull the trailer off road with non-dry conditions.

Unloaded I run 65 psi and have not had any rubbing, loaded I go to tire max of 80 psi.
I have not actually messured the gap between the tires under load, and yes I have had them rub if I hit a large hole or bump in the fields or on back roads. Running on the hi-way has not shown any rub issues.

chevmeister
Are you running the differnt tire sizes front/back on a 4x4? Even with that small of a difference between front and back circumference, can rip the transfer case out if you happen to hit dry pavement and forget to take it out of 4x4.

weekilty
the upside with going to the 265's on the front is the 3415# capacity vs the 235's capicity of 3042# using load range 'E' tires. I run a goose neck and load it heavy, and have never gotten close to the max front axle max capicity. I guess if you were going to run a slide in camper, you may end up with more weight on the front end. The front axle max on the door on my 04 is 5885 if I remember correctly, so the additional capacity of the 265's is lost.yes i run this combo on my 4x4, as far as the transfer case if you run diferent pressure front to rear the circumference changes more..... and as far as the backs being a little larger HJAT took care of that.
main reason for the 265s was so the front end floats. the 215s constantly got stuck in the mud and wore like crap from running unloaded all the time. the 265s handle better and off road performance is much better(construction sites).

actual specs of tires i got off bfgoodrich website

tire size height revs per mile Capacity

LT235/85R16/E 31.7 656 3042@80
LT265/75R16/D 31.7 656 3042@65

In all actuality the transfer case makes less noise now than with the bald rears and severly chopped front tires. on hard pavement ive had it to 90 in 4x4, closed road and it hasnt blown yet


Clearance on the rears is about 3/4" havent had them touch yet, except on uneven surfaces, bumps, potholes etc.. tires show no signs of sidewall wear running BFG A/T KO. had at most 3900# in the bed. 2500# on or behind the axle.

Thank you boys ! I am stoked to read of your experience. I am picking up a 2005 3500 4x4 dooley duramax on April 1st and was temped to buy toyo 255 85 16s all around. Truck is out of Chevy commercial line, which is nothing special just with small 9 foot flat bed but still has dinky 215s. I ran 235s all around on my 1989 GMC dooley Camper off road with great performance. However the 2005 rear fuel tank low position on this commercial model really concerns me. I do not care about any extra width, just clearance. one tire dealer said some spacer needed in rear. Any thoughts welcome !

Newby,
Bend,Oregon

with 255 you will need spacers
215/85-16 is 30.48 tall 8.41 wide
235/85-16 is 31.90 tall 9.29 wide
255/85-16 is 33.21 tall 10.04 wide
i have about 3/4 between my 235/85-16, if you figure the diference to 255 your gonna rub without spacers. 10.04 - 9.29 = .75"
height difference is 33.21 - 31.90 = 1.31" or 1 5/16 in height. are the spacers worth 5/8 in ride height??

boatdude: Are you sure that your spacers are 2"?

I am running 285's with 2" spacers (see prior posts for pictures) -- almost a 1" gap between the rears. I don't do any heavy towing, but with a 1,000 lbs. of sand bags in the bed and a 6,000 lb trailer hooked to the truck, the gap is still nearly an inch.