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Discussion Starter · #1 · (Edited)
Lets talk tires, its a topic I have a lot of experience in since i grew up around the industry!

I'll start by offering all the OE specs that I have available so you know what your starting with.

After that lets talk about proper maintenance of your tires. Lets face it, at today's prices tires are an investment and with a little attention you can help protect that investment!

And last but not least a Q&A!

2001-2007 GM 2500HD GMT800 SRW Trucks
LT245/75R16 = 30.7x9.80R16 Load Range E/10Ply, Load Rated @ 3042LBS
8x6.5"/165.1 Bolt Pattern
16x6.5" Wheel w/ +25 Off Set / 4.667 Back Spacing

Alternative Tire Size:
LT235/85R16 = 31.7x9.40R16
LT265/75R16 = 31.9x10.5R16
LT285/75R16 = 33.0x11.3R16, will require turning up the torsion bars, also recommended to mount onto a 7"-8" wide wheel

LT245/70R17 = 30.6x9.80R17
LT275/65R17 = 31.2x11.0R17
LT245/75R17 = 31.5x9.80R17
LT235/80R17 = 31.8x9.30R17
LT265/70R17 = 31.9x10.7R17
LT285/70R17 = 32.8x11.5R17, will require turning up the torsion bars, depending on wheel offset some trimming also
LT305/65R17 = 32.8x12.2R17, will require turning up the torsion bars, depending on wheel offset some trimming also

LT265/65R18 = 31.7x10.7R18
LT275/65R18 = 32.1x11.0R18, will require turning up the torsion bars, depending on wheel offset some trimming also
LT265/70R18 = 32.6x10.7R18, will require turning up the torsion bars, depending on wheel offset some trimming also
LT285/65R18 = 32.7x11.5R18, will require turning up the torsion bars, depending on wheel offset some trimming also
LT275/70R18 = 33.2x11.0R18, will require turning up the torsion bars, depending on wheel offset some trimming also

LT265/60R20 = 32.5x10.7R20, will require turning up the torsion bars, depending on wheel offset some trimming also
LT285/55R20 = 32.5x11.7R20, will require turning up the torsion bars, depending on wheel offset some trimming also


2001-2007 GM 3500HD GMT800 SRW Trucks
LT265-75R16 = 31.9x10.5R16 Load Range E/10Ply, load Rated @ 3415LBS
8x6.5"/165.1 Bolt Pattern
16x6.5" Wheel w/ +25 Off Set / 4.667 Back Spacing

Alternative Tire Size:
LT235/85R16 = 31.7x9.40R16
LT285/75R16 = 33.0x11.3R16, will require turning up the torsion bars, also recommended to mount onto a 7"-8" wide wheel

LT235/80R17 = 31.8x9.30R17
LT265/70R17 = 31.9x10.7R17
LT285/70R17 = 32.8x11.5R17, will require turning up the torsion bars, depending on wheel offset some trimming also
LT305/65R17 = 32.8x12.2R17, will require turning up the torsion bars, depending on wheel offset some trimming also

LT265/65R18 = 31.7x10.7R18
LT275/65R18 = 32.1x11.0R18, will require turning up the torsion bars, depending on wheel offset some trimming also
LT265/70R18 = 32.6x10.7R18, will require turning up the torsion bars, depending on wheel offset some trimming also
LT285/65R18 = 32.7x11.5R18, will require turning up the torsion bars, depending on wheel offset some trimming also
LT275/70R18 = 33.2x11.0R18, will require turning up the torsion bars, depending on wheel offset some trimming also

LT265/60R20 = 32.5x10.7R20, will require turning up the torsion bars, depending on wheel offset some trimming also
LT285/55R20 = 32.5x11.7R20, will require turning up the torsion bars, depending on wheel offset some trimming also


2001-02 GM 3500HD GMT800 DRW Trucks(Classic Style)
LT225/75R16 = 29.5x8.80R16 Load Range E/10Ply, Load Rated @ 2680LBS
8x6.5"/165.1 Bolt Pattern
16x6.5" Wheel

Alternative Sizes:
LT215/85R16 = 30.6x8.50R16
LT235/85R16 = 31.7x9.40R16


2003-07 GM 3500HD GMT800 DRW Trucks(Classic Style)
LT215/85R16 = 30.6x8.50R16 Load Range E/10Ply, Load Rated @ 2680LBS
8x6.5"/165.1 Bolt Pattern
16x6.5" Wheel

Alternative Sizes:
LT235/85R16 = 31.7x9.40R16


2007.5-10 GM 2500/3500HD GMT900 SRW Trucks
LT245/75R16 = 30.7x9.80R16 Load Range E/10Ply, Load Rated @ 3042LBS
LT245/75R17 = 31.5x9.80R17 Load Range E/10Ply, Load Rated @ 3000LBS
LT265/70R17 = 31.9x10.7R17 Load Range E/10Ply, Load Rated @ 3195LBS
8x6.5"/165.1 Bolt Pattern
16x6.5" Wheel w/ +28 Off Set / 4.785 Back Spacing
17x7.5" Wheel w/ +28 Off Set / 5.531 Back Spacing

Alternative Tire Size:
LT235/85R16 = 31.7x9.40R16
LT265/75R16 = 31.9x10.5R16
LT285/75R16 = 33.0x11.3R16, will require turning up the torsion bars, also recommended to mount onto a 7"-8" wide wheel

LT245/70R17 = 30.6x9.80R17
LT275/65R17 = 31.2x11.0R17
LT245/75R17 = 31.5x9.80R17
LT235/80R17 = 31.8x9.30R17
LT265/70R17 = 31.9x10.7R17
LT285/70R17 = 32.8x11.5R17, will require turning up the torsion bars, depending on wheel offset some trimming also
LT305/65R17 = 32.8x12.2R17, will require turning up the torsion bars, depending on wheel offset some trimming also

LT265/65R18 = 31.7x10.7R18
LT275/65R18 = 32.1x11.0R18, will require turning up the torsion bars, depending on wheel offset some trimming also
LT265/70R18 = 32.6x10.7R18
LT285/65R18 = 32.7x11.5R18, will require turning up the torsion bars, depending on wheel offset some trimming also
LT275/70R18 = 33.2x11.0R18, will require turning up the torsion bars, depending on wheel offset some trimming also

LT265/60R20 = 32.5x10.7R20
LT285/55R20 = 32.5x11.7R20, will require turning up the torsion bars, depending on wheel offset some trimming also


2007.5-10 GM 3500HD GMT900 DRW Trucks
LT225/75R17 = 30.6x8.80R17 Load Range E/10Ply, Load Rated @ 2755LBS
8x6.5"/165.1 Bolt Pattern
17x6.5" Wheel

Alternative Sizes:
LT245/75R17 = 31.5x9.80R17
LT235/80R17 = 31.8x9.30R17


2011-13 GM 2500/3500HD GMT900HD SRW Trucks
LT245/75R17 = 31.5x9.80R17 Load Range E/10Ply, Load Rated @ 3000LBS
LT265/70R17 = 31.9x10.7R17 Load Range E/10Ply, Load Rated @ 3195LBS
LT265/70R18 = 32.6x10.7R18 Load Range E/10Ply, Load Rated @ 3525LBS
LT265/60R20 = 32.5x10.7R20 Load Range E/10Ply, Load Rated @ 3195LBS
8x180mm Bolt pattern
17x7.5 Wheel w/ +44 Off Set / 5.981 Back Spacing
18x8.0 Wheel w/ +44Off Set / 6.264" Back Spacing
20x8.5 Wheel w/ +44Off Set / 6.548" Back Spacing

Alternative Tire Size:
LT275/65R17 = 31.2x11.0R17
LT245/75R17 = 31.5x9.80R17
LT235/80R17 = 31.8x9.30R17
LT265/70R17 = 31.9x10.7R17
LT285/70R17 = 32.8x11.5R17, will require turning up the torsion bars, depending on wheel offset some trimming also
LT305/65R17 = 32.8x12.2R17, will require turning up the torsion bars, depending on wheel offset some trimming also

LT265/65R18 = 31.7x10.7R18
LT275/65R18 = 32.1x11.0R18, will require turning up the torsion bars, depending on wheel offset some trimming also
LT285/65R18 = 32.7x11.5R18, will require turning up the torsion bars, depending on wheel offset some trimming also
LT275/70R18 = 33.2x11.0R18, will require turning up the torsion bars, depending on wheel offset some trimming also

LT285/55R20 = 32.5x11.7R20, will require turning up the torsion bars, depending on wheel offset some trimming also


2011-13 GM 3500HD GMT900HD DRW Trucks
LT235/80R17 = 31.8x9.30R17 Load Range E/10Ply, Load Rated @ 3085LBS
8x210mm Bolt Pattern
17x6.5 Wheel w/ +137 Off Set / 9.076 Back Spacing


Proper Air Pressure, I can not stress this enough! Proper PSI is one of the most important factors in tires lasting a long time but also in tires performing as they are intended to!

The MAX PSI on the side of your tire is only there to tell you what the PSI should be at if you have that amount of weight on the tire.

If your tires are wearing more in the center of the tread lower the air PSI by 5PSI and inspect tire wear again, repeat if necessary.
If your tires are wearing more on BOTH shoulders add 5PSI and inspect tire wear again, repeat if necessary.
If your tires are wearing more on ONE shoulder, inspect suspension parts for wore or damage parts then have the vehicle aligned.
If your tires form a irregular wear pattern or "cupped out" have them rotated and rebalanced. Tires out of balance can cause irregular wear patterns.
If your truck is experiencing a vibration that above 40MPH and seemly changes with speed, you need to have them rebalanced.
If your truck is experiencing a vibration at low speeds and also at higher speeds, have the tires inspected for slipping / shifting belts.


Proper Rotations:
I would recommend to have your tires rotated every 5,000miles or 6Months, why, it gives you a chance to inspect tire wear and also check your brakes.


Q&A

Q: What is the largest tire that will fit my truck?
A: Not a fair question! I get this question a lot so I would like to shed some light on this! There really isn't an accurate answer for this question without first knowing a lot of other factors such as wheel size, offset and suspension changes made to the truck!

Q: Do I need to stay with a Load Range E/10Ply tire?
A: No, there is no law requiring a X ply tire on Light Duty trucks! However DOT and manufacturers strongly recommend that you maintain or exceed the load rating of your OE tire.

Q: Will larger tires affect my speedometer?
A: Yes, however with today's technology you can either purchase a device that can recalibrate your speedometer or have someone use software such as EFILive.

Q: Will larger tires affect my MPG?
A: Yes & No, larger tires as in heavier will affect your economy negatively since they will require more energy to roll, also keep in mind that a more aggressive tread will also increase rolling resistance and will affect MPGs negatively. A taller tire that offers less rolling resistance then your current tires can help increase your MPGs, rolling resistance will also directly affect MPGs!

Q: What type of tire rotation is proper for my tires?
A: Typically tires are moved straight from the front to the rear! If you have tires that have not been properly rotated in the past you can help correct irregular wear patterns by Xing the tires from corner to corner! On duallys I typically move the front to the outside rear, outside rear to the inside rear, and the inside rear to the front.

Q: How do I know when I need new tires?
A: DOT requires that tires are changed when they have 2/32nds of tread left on them, however it is strongly recommend that the tires be replaced when they have 4/32nds of tread left.
 

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Discussion Starter · #3 ·
most of it did...allthough my head hurts now..
 
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Discussion Starter · #5 ·
no,a deal is a deal Scott thats why we bought that Stroker.
 

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i have a poster i got from rough country that tells me what tires fit under what vehicle? it will tell me what i have to do or what it will take fit whatever size tire you would want to fit under whatever truck. Throw a name of a truck,year and what size tire out and ill tell you what you would have to do. poster only goes up to 05 tho.
 

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Discussion Starter · #8 ·
it vary's truck to truck but the sizes i posted are some of the most populars ones out there.
 

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Legennn... wait for it...
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one of the big 4wd magazines publishes a chart like that in one issue every year. It lists vehicles by make, model and years, then what will fit under it stock, and with various lifts and mods... including fender trimming
 

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How about explaining wheel offset and how it relates to backspacing.
For example, I am looking to run 285/70/17s or 295/70/17s on my 08
2500 4x4 with 17x9 wheels. Wheel backspacing is 4.50 and offset is
-12. What exactly does the -12 mean?
 

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I have an 08 2500 that came with the Z71 17" wheels. The tires look like pizza cutters and I would like to get much wider and a little taller tires. Anyone know the largest tire size to run with a leveling kit, stock wheels and a little trimming? It seems that the tire genius may be a part of this thread...
 

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Legennn... wait for it...
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How about explaining wheel offset and how it relates to backspacing.
For example, I am looking to run 285/70/17s or 295/70/17s on my 08
2500 4x4 with 17x9 wheels. Wheel backspacing is 4.50 and offset is
-12. What exactly does the -12 mean?
the -12 means that the hub of the wheel is 12(units) behind the centerline of the wheel. It's usually measured in millimeters.
 

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Yes offset is measured in mm.
It is the distance of the hub mounting surface in relation to the center line.

Therefore, a 0 offset wheel has the hub mounting surface exactly at the centre line of the wheel.
For example, a 9" wide wheel, with 0 offset, will have 4.5" back space.

Negative offset implys that the hub mounting surface is set back further resulting in a deep dish wheel.
For example, a 9" wide wheel, with -25mm offset, will have 3.5" back space.

Positive offset implys that the hub mounting suraface is closer to the font surface of the wheel resulting in a flush appearance at the face of the wheel.
For example, a 9" wide wheel, with +25mm offset, wil have 5.5" back space.

In my experience, you should aim to buy a set of wheels with the offset as close to stock as possible.
 

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Ok, then I'm confused. If the wheels I'm looking at are 9" wide and have 4.5" backspace, how can the offset be -12? Shouldn't it be zero?
 

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Ok, then I'm confused. If the wheels I'm looking at are 9" wide and have 4.5" backspace, how can the offset be -12? Shouldn't it be zero?
I'll try to find an article that explains it more clearly, but yes, I assume those wheels will have a 4.25" backspace.

Hopefully someone else will jump in here if my logic is flawed.
 

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Here is a clear article explaining offset:
Wheel Offsets - Discount Tire Direct

It seems I misinterpreted the meaning of backspacing and confused it with "rearspace".
Here is an image indicating rearspace:
http://images.fourwheeler.com/techarticles/wheels/129_0602_01_z+wheel_backspacing_offset+diagram.jpg

Backspacing is in fact measured from the outboard bolting surface to the plane of the outboard flange, pictured here:
http://tbn0.google.com/images?q=tbn...0612_02z%2Bford_mustang%2Bwheel_backspace.jpg

This is overly confusing and unnecessary information, IMO. The important factor is Offset. Knowing the wheel's offset, you can easily calculate exactly how much of the wheel will hang behind, and in front of the center line.
 

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You said anything over nine inches wide should have spacers so if i want to throw on 265 75 r16's i should space? or am i not quite at nine?
 

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Discussion Starter · #20 ·
the duallys are the only ones that need spacers when running a tire over 9"'s wide,to keep the tires from touching each other,so a non DRW truck doesn't need spacers.

omcvay,the biggest tire you can clear on your truck with the Torsion bars raised and minor trimming is a LT285-70R17 which is roughly 33" tall so that will fill in your wheel well very nicely.

BS/Offset,from my experience with wheels if you have a 8" wide wheel you want a 4.0-4.5" BP for the best look but with that BS you can clear a taller tire without any problems other then the usual trimming and such
if you have a 9"-10" wide wheel you want to stay with a 4.5-5.0"BP and even then you will need a leveling kit to run a larger tire(32" or taller)or the tires will rub the frame or innerfender(or both)when turning even with the Torsion bars raised plus with the wide wheels your tires will stick out the side a bit so you don't want to travel gravel roads.to be honest the whole BS/Offset is still new to me also so those numbers are just from our experience selling wheels.
BS=Back Spacing
 
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