285's Power Loss?

[SWDoodle]

I'm sure this topic has been discussed many times, but it's about time to replace my stock 245 pizza cutters with some new tread. Thinking about some Wrangler Pro Grades. Anyways my pick-up is a 2500HD with the 6.0/4.10 combo. I haul heavy at times (20K GCWR) when I'm hauling cattle, but it's not very often. My question pertains to power loss moving up to a 285/75/16 tire. I had this size on my 1500 5.3/4.10 and it looked awesome, but it road a lot rougher and I did notice some power/mileage loss. To me the 6.0 has more power than the 5.3 so I was wondering what ya'll think. I'm going to at least go to a 265 if anything. I'm a little concerned about a 285 on a stock rim, but I've seen alot of guys with this setup around. I'm not doing this for looks, I want more clearance in the front because I'm tired of ripping my air d**n off when I'm out in a pasture or when I go thru a ditch. Would a 285/85/16 be the way to go? I'm just thinking about less rolling resistance, but a taller tire. I dunno, tell me what you guys think. If I had a D-Max it would be 285's for sure.

[Ranger]

I never had any problems pulling heavy loads with my HD...I even pulled a fully loaded trailer (probably around 7,500 lbs) up a ramp to a parking structure and it didn't require a whole lot of throttle to go up. If you are worried then just get the 265s, both will look better than the 245s.

[Wingnut]

I think you'll be fine. You could always go with the 265's and crank the t-bars just a little.

[wellinghurst]

I would stick with 265's on the stock rims. Plenty of guys put 285s on stock rims, but the tires are not recommended for rims that skinny, plus they just look too fat I think. My dad runs his on stock rims and I love giving him a hard time with it.

 

As far as power goes, I noticed a difference on take off, but rolling down the highway I don't see much difference. The biggest difference comes with braking.....

 

If you air dam is causing that much trouble-take it off... I am thinking of taking mine off and re-wiring the fogs to a set of lights on my brush guard.

[Q101ATFD]

I would not recommend putting a 285 on a stock 16x6.5 rim. There is just too much difference in the width of the tire and wheel - making it more prone to blow out if you hit a good sized rock or hole in the pasture - or pothole on the road.

 

If you were still considering it, you mentioned maybe a 285/85R16 tire. That combination will, in effect, reduce your rear gear ratio to ~3.47:1 - down from your 4.10, and even below the 3.83 gear. This gear will keep your engine bogged down more, reducing your power. I would suggest getting a good set of 265's on maybe a 17x7.5" rim if you can afford the upgrade. The 265's on a 17" wheel will add almost 1.5" of height - and if you need more, just give the torsion bars a few cranks too.

[sonjaab]

Not to mention ..........make sure the new tires you get are LT (light truck)

rated not the regular passenger car tires (like MANY larger sizes are) that

many folks slap on their trucks because they believe in that " bigger is

better myth" attitude !!!!!!!!!!!!!!!!!!

 

Yet they fail to realize that they are now running on a larger size tire

yet have only 2 ply tread and sidewalls and skimpy weight rating instead

of the "PUNY" 245s with 4 -6-10 plys and higher weight rating !

[whitesnake01]

I opted for an upgrade to 285/75R16s on my pickpup (2500HD with a DMAX). Ended up getting two sets of new wheels and two sets of new tires (michelin with polished aluminum for the summer and toyo with black steel for the winter/snow). Probably a 10% hit to fuel economy doing regular highway driving and about the same towing my 8,300 lbs+ camper. The performance reduction is noticeable when towing, although this is somewhat subjective. I am debating if to upgrade to 4.10 gears from the stock 3.73, since I am concerned enough about the performance when I get into more hills when I tow. Its not that I do not think it can make it up the hills when I tow. Its just that (a) the water pump runs slower when you need it the most and (b) that I run into black smoke scenarios more often than with 245s.

 

GM does not support the 285 tire size if you ask them to recalibrate the speedo but they do appear to support the 265. My dealer claimed they did support the 285, but after they applied their change, it had done nothing more than to recalibrate some abs setting, while the speedo and odometer were left thinking the truck still had 245s.

 

When it comes time to upgrade my truck, I'll opt for the new 265s on R17s instead which can now be had on the 2500HD. That'll basically be very close to the 285s on R16 while being supported by GM, etc. All in all the 285s look very sharp.

 

Good luck!

[wellinghurst]

Not to mention ..........make sure the new tires you get are LT (light truck)

rated not the regular passenger car tires (like MANY larger sizes are) that

many folks slap on their trucks because they believe in that " bigger is

better myth" attitude !!!!!!!!!!!!!!!!!!

 

Yet they fail to realize that they are now running on a larger size tire

yet have only 2 ply tread and sidewalls and skimpy weight rating instead

of the "PUNY" 245s with 4 -6-10 plys and higher weight rating !

 

There is no way you should put LT tires on a 2500HD. Most shops won't even do it if you want them to because it's not right. They require 10-ply, and 8-ply will work with bigger tires (read the sidewall ratings). LT tires are for SUVs and small trucks.

[SWDoodle]

I think that I'll just stick with the 265's since I'll be keeping my stock rims. One of these days I'd like to get some 17" or 18" wheels for it, but can't afford it right now. I don't think I want to go to a 285/85/16 if it drops the ratio that much. This pickup has decent power, but I definately don't want to lose any. Thanks for all the replies.

[Silverado4x4]

When I had my 2500 HD Dmax I put 285s on and the truck wondered down the road due to the 285 will crown in the middle of the tire from the rim pulling the sidewalls in, was real bad towing, kept them for about 2 months and went back to the stock size and sold the 285s. Yes you will loose some power.

[Q101ATFD]

There is no way you should put LT tires on a 2500HD. Most shops won't even do it if you want them to because it's not right. They require 10-ply, and 8-ply will work with bigger tires (read the sidewall ratings). LT tires are for SUVs and small trucks.

 

What are you talking about??

 

LT tires are made for what we drive - Light Trucks (1-ton or less)...

 

A medium or commercial truck tire goes on something like a Kodiak.

[local392-496]

I put 285s on my 2500HD 8.1 EC, it did reduce the power a small amount out of the hole. And at first it did seam like they wandered a little bit on the road but it went away. Now they are fine, won't trade them for anything. They look great on the truck to. You will have cank the t bars, and on mine I had to trim the front bumper trim just a small bit, they rubbed it in turns. The Goodyears Wrangler Progrades are awesome, did u notice how thick the rim guard area is on them? Do It!!! Just one guy's thought.

[wellinghurst]

There is no way you should put LT tires on a 2500HD. Most shops won't even do it if you want them to because it's not right. They require 10-ply, and 8-ply will work with bigger tires (read the sidewall ratings). LT tires are for SUVs and small trucks.

 

What are you talking about??

 

LT tires are made for what we drive - Light Trucks (1-ton or less)...

 

A medium or commercial truck tire goes on something like a Kodiak.

 

 

There is a difference between LT tires and tires that are 8 ply or 10 ply (load range D or E).

 

LT tires are deignated in different ways, but they are basically made for lighter vehicles like most SUVs and small trucks that aren't rated for heavy towing. You can get away with putting LT tires (load range c) on an HD if you can find someone who will put them on, but they are not "legal" on some states. They are not made to handle the HD truck and towing possiblly 9-10,000 lbs or more. According to the ratings, HD trucks should run 8-10 ply tires, not LT rated tires. Just look at the sidewall and you will see how much weight the different tires can safely handle.

 

I think we are discussing semantics more than anything. Some people call the tires I am talking about LT tires. I have owned SUVs and like to differentiate between the two.

[SWDoodle]

I would not recommend putting a 285 on a stock 16x6.5 rim. There is just too much difference in the width of the tire and wheel - making it more prone to blow out if you hit a good sized rock or hole in the pasture - or pothole on the road.

 

If you were still considering it, you mentioned maybe a 285/85R16 tire. That combination will, in effect, reduce your rear gear ratio to ~3.47:1 - down from your 4.10, and even below the 3.83 gear. This gear will keep your engine bogged down more, reducing your power. I would suggest getting a good set of 265's on maybe a 17x7.5" rim if you can afford the upgrade. The 265's on a 17" wheel will add almost 1.5" of height - and if you need more, just give the torsion bars a few cranks too.

 

I screwed up on the tire size mentioned before. I meant to say "235/85/16" not 285/85/16. Does anyone have any experience with this tire size? I looked at the specs and they are the same height, but a little narrower than the stock size.

[Silverado4x4]

I put 285s on my 2500HD 8.1 EC, it did reduce the power a small amount out of the hole. And at first it did seam like they wandered a little bit on the road but it went away. Now they are fine, won't trade them for anything. They look great on the truck to. You will have cank the t bars, and on mine I had to trim the front bumper trim just a small bit, they rubbed it in turns. The Goodyears Wrangler Progrades are awesome, did u notice how thick the rim guard area is on them? Do It!!! Just one guy's thought.

 

The reason the wandering went away is because you wore the centers down some to match the edges of the tires that were not contacting the road as good as the center making them flatter.