285s on 2500HD?

Russell420 · October 12, 2006

I want larger tires for my '06 2500HD, but I do NOT want to mess with the torsion bars or trim any plastic, and I don't what them to rub. Can I fit 285/75-16 BFG all terrains on my stock wheels without any modifications or adjustments? Anybody been able to do this? I also want to be able to use the truck to haul whatever it is designed to haul and tow as well, so if putting these larger tires on it means sacrificing its hauling or towing abilities, let me know. I know a lot of people run the 285s on the stock wheels, but there doesn't seem to be any concensus on whether you must trim plastic or adjust the torsion bars to do it. BTW my truck is otherwise stock. Thanks for your help.

Russell420

Shaners · October 12, 2006

You will most likely have to crank the torsion bars, and trim some plastic on the inner fender wells if you want to run 285's.

285's will also change your effective gear ratio, so the truck will be a little more sluggish under acceleration.

I'm running 265/75/16's on my HD and I'm very happy with the way the extra height and width fill the wheel wells. With 265's there is no cranking or trimming needed.

mmmikkke · October 13, 2006

I put 285's on my '05 2500HD on the factory aluminum rims. The rims are only 6.5" wide, though, and that's 1.5" less than the minimum width that the 285/75R16 is designed for. That means you are using the tire suboptimally, and you won't get the best handling as a result. The sidewall stiffeners are not in the position that they're designed to be in.

265's might be a better choice if you are looking to get the best handling and stay with the factory rims.

But if youwant to know more about what's required for 285's, click on "view vehicles" below my avatar, and you can find one picture there that shows the only trimming you will need to do. It's trivial, and you can do it in 5 minutes with a hacksaw, without anybody being able to detect it after you're done. I did not crank my t-bars at all. Just that itty bitty little trim job.

If you put 8" wide aftermarket wheels on along with 285's, you get better handling. But at the same time, you get a worse clearance situation because you're moving the tire centerlines outward. The trim would have to be more severe... But sometimes that's the fun part of having a truck...change one thing, and then you have to change something else to make it work better, and then something else, and something else...

Russell420 · October 13, 2006

Thanks for the replies. Sounds like the 265s might be a better choice for me. Does anyone have any pics of a 2500hd with 265/75-16s on stock wheels? I'd like to see what they'll look like on the truck. Thanks.

Russell420

drewtori · October 15, 2006

i have 265 on mine there nice but i think 285 would look nicer personally. my cousin hase the same truck but 4wd and his came stock with 285 on the stock rim and his was brand new. i know chevy put them on but i dont know nor does he if chevy cranked the t bars. i know 285s are not stock but for what ever reason they put thewm on his truck so good luck.

Mattt · October 16, 2006

There is no concensus on whether 285s fit or not because every truck is different coming right out of the factory. No two trucks are EXACTLY the same. Some need bars cranked, some dont. some need trimming, some dont. If these trucks were all exactly the same from the factory, a concensus could be had.

My stock 2500hd 4wd had 285s on stock rims with no mods, but I didnt buy the truck new. I bought it two years old and it appeared to be totally stock when I got it.

265 is probably you best bet if you dont want to have to change anything, or worry about reduced power when towing. You will lose some gear ratio even going with the 265s, but it will be less than if you go 285s. Stock 245s are roughly 29-30" tall. 265s are roughly 31" tall, 285s are roughly 33" tall. As you go up in size, you are losing effective gear ratio.

gmcjoe · October 16, 2006

I want larger tires for my '06 2500HD, but I do NOT want to mess with the torsion bars or trim any plastic, and I don't what them to rub. Can I fit 285/75-16 BFG all terrains on my stock wheels without any modifications or adjustments? Anybody been able to do this? I also want to be able to use the truck to haul whatever it is designed to haul and tow as well, so if putting these larger tires on it means sacrificing its hauling or towing abilities, let me know. I know a lot of people run the 285s on the stock wheels, but there doesn't seem to be any concensus on whether you must trim plastic or adjust the torsion bars to do it. BTW my truck is otherwise stock. Thanks for your help.

Russell420

<{POST_SNAPBACK}>

You can run those tires on an HD with no issues.

I run them on my 2000 Z71 with no mods and no rubbing

vxaxv17 · October 16, 2006

Thanks for the replies. Sounds like the 265s might be a better choice for me. Does anyone have any pics of a 2500hd with 265/75-16s on stock wheels? I'd like to see what they'll look like on the truck. Thanks.

Russell420

<{POST_SNAPBACK}>

I have 265/75R16 BFG A/Ts on my 2500HD right now. They look like this:

They are pretty d**n worn down at this point and i'll be replacing them soon but you get the idea.

Jim

larry arizona · October 16, 2006

They fit fine with no mods on a 1500 but they come with wider rims than the 2500. The only issue with the 2500 is the rim width. If they do not rub on a 1500 they will not rub on a 2500.

You will need to get speedo recal'd for a 2500 due to extreme diameter difference in the 245 versus 285's

dizzy · October 18, 2006

I would not recommend going larger than 265's if you pull a trailer. I installed BFG LT285/75R/16D's on my 2005 2500HD.

Stock tires were 245's or 30.0" diameter tires, they weighed 38lbs each.

The BFG Mud Terrain 285's are 33.1" diameter tires, they weighed slightly over 50lbs each. So no only are you trying to spin larger diameter wheels eating up torque, they weigh more.

As far as ride and handling goes? I think there was an improvement (especially in ride).

With 4.10 gears, 70MPH RPM drops 500RPM (think for me that was from 2800RPM to 2300RPM). Problem is pulling a travel trailer, cruise control becomes worthless as it is shifting up/down at every little elevation change like an overpass.

I have a HypertechIII, so reprogramming the speedo change was a no brainer. It sure sucks the gas with them larger tires. With the 245's I have no problem getting 12.8MPG around town and as high as 14MPG on freeway with long drives. With those 285's I was lucky to get 10MPG around town and pulling a trailer as low as 8MPG.

My 2000 Silverado LT 1500 w/5.3L Z71 4x4 had the 265's that truck got 15.7MPG around town and as high as 20MPG on the freeway (think I had 3.43 gears in it).

Here it is with the 285 BFG's installed:

1. I cranked up on the front torsion bars (just to level the truck).

2. I trimmed the corner off the inside corner of the lower facia, you can see where trimmed below. This is needed so 285's don't hit when turning.

SV Silverado · October 18, 2006

But the truck does look sweet. I guess that is the price you pay.

496SS · October 20, 2006

When I bought my '01 HD2500 new, I drove from the dealer strait to the tire shop and had 285's put on. No trimming or bar crank. I later adjusted the bars to level it out (hate that nose dive look). I ran these for 48,000 miles and when the tires wore out I changed to 8" Welds and new 285's which required a very minor trim inside the front wheel well for the rub when backing up and turning sharp. Just a little plastic with a cut off wheel. EASY!! and it looks so much better than those little 245's. I also have the 8.1 so it could care less about the added diameter and the bonus was a few less rpms on the highway.

Mattt · October 24, 2006

Dizzy, your poor mileage could be contributed to by the Mud Terrains. Ive got All Terrain 285s on mine, and my mileage did drop from the stock 245s, but not that drastic for in town driving. Im lucky to get 8 towing, but my trailer also weighs 10k-11k loaded. I average 12mpg in town, around 7 towing, and a bit better than 12 on hwy. driving. Ive heard that the rolling resistance is higher with an MT vs. an AT.

I had the same problem with OD and Cruise Control when towing, but getting my computer reprogrammed{Westers style, but done locally} solved many issues. My towing mileage went from 6.5mpg to 7.9, and it drove better afterwards. No more hunting between gears, and it keeps the TC locked up longer. I think 55% of the improvement out of the re-program is Better tranny control, and 45% of the improvement is the slight bump in power.

Ive noticed it gets a bit better mileage with 89 or higher octane and it seems to ping with 87. The increase in mileage is pretty much a wash with the additional cost of 89 or higher fuel vs. running 87.