This is probably the question that goes through each cruiserheads mind on multiple ocassions. Tire's cost a lot of money and you want to make sure you get the perfect set of tires for your hard earned cash. The problem is what's perfect for you, is not what's perfect for others.
How do I plan on using my truck?
The first thing you need to do is to define your long term plans for your truck. Tires last years and you don't want to have to change them 6 months down the road:
1) Do you plan to wheel your truck?
2) Do you have a lift, or are you going to have a lift for your truck.
3) Do you expect to be driving in winter conditions or mud.
4) Do you drive lots of highway miles.
Using a Larger Than Stock Tire
Clearance and traction are the primary factors to consider when going off-roading. Your vehicle will have to maneuver over and around obstacles and through terrain, and the right tire, along with compatible components, will give you an increase in both. A taller tire gives more clearance under the differential and chassis, and a wider tire, or change in tread pattern, can give more traction.
One thing to consider in a tire upgrade is fender clearance. Not only does your vehicle need sufficient clearance while at rest, but it must also accommodate maximum up and down travel and side to side tire movement caused by steering and cornering.
Another item worth noting is the affect the weight of a larger tire can have on braking. It's quite common, after upgrading to larger-than-stock tires, to note a decrease in stopping power or longer stopping distances. Many people upgrade their brake discs and/or pads to offset this slightly. Regardless, your driving style may need to change somewhat to accomodate the limits of your new tires.
Most people select Larger than stock tires. This thread won't discuss lifts and gears (use the search function):
Advantages of larger tires for off-road travel:
Disadvantages of taller tires
What is Siping? - Siping on a tire will provide additional traction and can be added later by most tire shops. This will be discussed later, but a lot of Mud Terrain tires do not come with siping and perform poorly on ice.
Here is a link on Siping to better explain:
Learning to Read a Sidewall - it's not Rocket Science
Summary of Tire Pressure-
The Stock 80 uses a P-metric tire (designated by the use of a P in the size i.e. P275/70/16), with a recommended inflation pressure of 32psi. When converting to a light truck tire (LT) which most A/T and Max Traction tires are (LT is designated on the sidewall next to the size i.e. LT275/70/16), you should add approximately 10psi to the factory recommended pressures. Based on the load charts (and this doesn't matter whether you are running a C, D, or E rated tire) you should adjust your base pressure to be as follows when changing to an LT tire:
275/70/16, 265/75/16 - 42-45psi,
285/75/16, 305/70/16 - 40-42 psi,
295/75/16- 38-40psi,
315/75/16- 36-40 psi.
You should not go below the minimum pressures above. If you have a truck that has a lot of extra weight (i.e. sliders, bull bar, winch, bumpers, etc.) add 5-8psi to the above.
Tire Sizes -
We should be a little more accurate in our sizing for the faq, at least have the information out there. The actual sizes of various tires are as follows:
275/70/16- 31.2"
265/75/16- 31.8"
285/75/16- 32.8"
305/70/16- 33.0"
295/75/16- 33.2"
315/75/16- 34.6"
Note these are BFG A/T sizes, various manufactures will vary by up to .2" but are generally at the same size.
For reference traditional inch size tires measure as follows:
31x10.5 - 30.7"
32x 11.5- 31.7"
33x 12.5- 32.7"
35x 12.5- 34.7"
So when computing tire sizes, keep in mind the OEM tire is really what would be 31.5" tire under traditional sizing.
Understanding Tire Tread
Tread - Note BF Goodrich tires are used below for examples.
Tire tread comes in all sorts of flavors, however, when off-road performance is the focus "All Terrain Tread" and "Mud Tread" are probably best suited for the task.
Street/Performance Tires/ All season - These are typically radial tires were the only consideration is on pavement performance.
All Terrians- All Terrain tread performs well under a variety of off-highway conditions and to some extent has closed the street/trail performance gap. The closed tread design is usually quiet on the highway, yet noisier than a street tire, and performs well on rocks, sand, and on the highway. As you might expect, they tend to load up with mud, but some of the AT designs perform surprisingly well in muddy conditions. For highway driving with minimal trail use, the AT design is an excellent choice.
Mud Terrians - Mud Tires, and this may not surprise you, perform well in mud. Beyond the obvious superior performance in mud, they generally also do well on rocks and in deep snow. The MT is at its worst in rain and some can be outright dangerous in icy conditions. The performance on ice for many mud tires is due to a lack any siping and consist of large flat surfaces, ie the ends of the tread lugs. Large flat surface on ice equals no traction and greatly lessens control as well. Some mud tires however are siped in an effort to improve their performance on ice. Siping should be a deciding factor if you live in areas that get icy roads. Another possible disadvantage of the aggressive tread of the Mud Tires is that they have a tendency to be noisy, however, for the true mudder, this is hardly an issue.
Thse more aggressive Tires (May be still classified as an MTR, but are much more agressive)- Some specialized tires, like the BFG Krawler, were designed to be the leader in one category - in this case, rock crawling. This is one of the fastest growing aspects of competative offroading, and these tires reflect th eleading edge in tire technology - super sticky computer designed void pattern and specific rubber compounds designed to resist abrasion are used. Available only in selected sizes over 35", these would be ideal on a rock buggy, but not so good on the street. They are, however, street legal.
Mil-Spec Tires and Non-DOT Tires -
Micheline Mil-spec XML
Non-DOT Tires
Other Threads or articles related to Tires:
cary's thread on tire inflation
Walking Eagles Thread on C vs D tires
Landtoys thread on Gross weight and tires
Christo Slee's article on Lift size vs. Tire Size
Note- will clean up and add nice links later for the below
https://forum.ih8mud.com/showthread.p...l+narrow+tires
https://forum.ih8mud.com/showthread.p...narrow+tire s
https://forum.ih8mud.com/showthread.p...narrow+tire s
https://forum.ih8mud.com/showthread.p...ighlight=tires
https://forum.ih8mud.com/showthread.p...narrow+tire s
https://forum.ih8mud.com/showthread.p...l+narrow+tires
So which tires are right for me?
Once you have defined your current and future plans for your truck, you can then begin to wade through all the different varieties.
If your primary concern is highway performance with an ocassional off road expedition adventure, an All Terrain tire might be the ticket. If that's the case, you now have to decide which tire.
How do I plan on using my truck?
The first thing you need to do is to define your long term plans for your truck. Tires last years and you don't want to have to change them 6 months down the road:
1) Do you plan to wheel your truck?
2) Do you have a lift, or are you going to have a lift for your truck.
3) Do you expect to be driving in winter conditions or mud.
4) Do you drive lots of highway miles.
Using a Larger Than Stock Tire
Clearance and traction are the primary factors to consider when going off-roading. Your vehicle will have to maneuver over and around obstacles and through terrain, and the right tire, along with compatible components, will give you an increase in both. A taller tire gives more clearance under the differential and chassis, and a wider tire, or change in tread pattern, can give more traction.
One thing to consider in a tire upgrade is fender clearance. Not only does your vehicle need sufficient clearance while at rest, but it must also accommodate maximum up and down travel and side to side tire movement caused by steering and cornering.
Another item worth noting is the affect the weight of a larger tire can have on braking. It's quite common, after upgrading to larger-than-stock tires, to note a decrease in stopping power or longer stopping distances. Many people upgrade their brake discs and/or pads to offset this slightly. Regardless, your driving style may need to change somewhat to accomodate the limits of your new tires.
Most people select Larger than stock tires. This thread won't discuss lifts and gears (use the search function):
- The 305 sized tire is the largest tire that can fit in the stock spare location.
- 33" (285, 295, 305) sized tires will work fine with stock gears.
- The larger tire you run, the more your speedometer will be off. Stock is a 31" tire, so if you are running a 33" tire, your speedomter and odometer will be off by and you will need to multiply it by a factor of the difference over stock, for 33" tires (33/31) 1.065 is the factor.
Advantages of larger tires for off-road travel:
- They could make your vehicle look better
- Larger footprints provide more flotation on soft surfaces.
- Larger footprints mean less likely flat tires.
- Larger footprints mean an increase in traction.
- Taller sidewalls mean more cushion between nasty rocks and the rim.
- Taller sidewalls mean better ride comfort.
- #1 and main reason is CLEARANCE!!!
Disadvantages of taller tires
- A loss of performance.
- With every inch over stock diameter you'll lose 3.5% of torque.
- Larger tires have a negative influence on stopping power.
- Draw back of heavier tires is a possible decrease of comfort on pavement.
- More unsprung weight means a rougher ride on pavement.
- Draw back of wider tires is a loss of steering accuracy.
- Wider tires have a higher rolling resistance resulting in higher gas consumption
What is Siping? - Siping on a tire will provide additional traction and can be added later by most tire shops. This will be discussed later, but a lot of Mud Terrain tires do not come with siping and perform poorly on ice.
Here is a link on Siping to better explain:
Learning to Read a Sidewall - it's not Rocket Science
Example: P215/65R15 89H
"P" means this is a passenger car tire (as opposed to a tire made for a truck or other vehicle). P-metric is the U.S. version of a metric tire-sizing system.
"215" Section Width: The width of the tire in millimeters from sidewall to sidewall. This measurement varies depending on the width of the rim to which the tire is fitted: larger on a wider rim, smaller on a narrow rim. The number on the side of tire indicates the width measured with the tire fitted to the recommended rim width.
"65" Aspect Ratio: The tires sidewall height. The ratio of height to width; this tire's height is 65% of its width.
"R" Construction: How the plies are constructed in the tire carcass. "R" means radial. "B" in place of the "R" means the tire is belted bias construction. "D" in place of the "R" means diagonal bias construction.
"15" Rim Diameter: The diameter of the wheel in inches.
"89"Load Index: This tire has an industry-standard maximum load of 1,279 lbs. Different numbers correspond to different maximum loads. The maximum load is shown in lbs. (pounds) and in kg (kilograms), and maximum pressure in PSI (pounds per square inch) and in kPa (kilopascals). Kilograms and kilopascals are metric units of measurement.
"H"Speed Rating: This tire has an industry-standard maximum service speed of 130 mph. Tires using an older European system carry the speed rating in the size description: 215/65HR15. Different letters correspond to different maximum service speeds.
The letters "DOT" certify compliance with all applicable safety standards established by the U.S. Department of Transportation (DOT). Adjacent to this is a tire identification or serial number; a combination of numbers and letters with up to 11 digits.
ALL-SEASON DESIGNATION
This is a marking which means that the tire meets M&S/M+S requirements without the drawbacks of noise and rolling resistance associated with the traditional deep-lug winter tires. The M&S/M+S designation means that the tire is suitable for normal all-weather driving applications. Tires that meet the requirements of the M& S designation have better winter traction compared to those without the M&S symbol.
North American tire manufacturers and the RMA have established a voluntary, industry-wide definition for passenger and light truck tires intended for use in SEVERE SNOW CONDITIONS. Tires must meet a performance-based criteria featuring tread pattern, construction elements and materials which generally provide snow performance superior to that of tires bearing the RMA current M&S Rating. Such tires will display a mountain/snowflake symbol.
The sidewall also shows the type of cord and number of plies in the sidewall and under the tread.
For larger off-road focus tire sizes, the rules are the same:
33/12.5/15
33" overall diameter - usually rounded up a bit (33" = 32.7" or so, but this varies by tire and manufacturer)
12.5 inches wide as measured across the tread-face
15" rim diameter
Reading Tire Age from the sidewall:
When it comes to determining the age of a tire, it is easy to identify when a tire was manufactured by reading its Tire Identification Code (serial number). Unlike vehicle identification numbers (VINs) and the serial numbers used on many other consumer goods (which identify one specific item), Tire Identification Codes are really batch codes that identify which week and year the tire was produced.
The U.S. Department of Transportation (DOT) National Highway Traffic Safety Administration (NHTSA) requires that Tire Identification Code be a combination of eleven or twelve letters and numbers that identify the manufacturing location, tire size, manufacturer's code, and week and year the tire was manufactured.
Today, the week and year the tire was manufactured is contained in the last four digits of the serial number, with the 2 digits used to identify the week a tire was manufactured immediately preceding the 2 digits used to identify the year.
Examples of tires manufactured since 2000 with this Tire Identification Code format:
XXXXXXXX 0600
XXXXXXXX 0600 06 - Manufactured during the 06th week of the year
XXXXXXXX 0600 00 - Manufactured during 2000
And
XXXXXXXX 0604
XXXXXXXX 0600 06 - Manufactured during the 06th week of the year
XXXXXXXX 0604 04 - Manufactured during 2004
The Tire Identification Code for tires produced prior to 2000 was based on the assumption that no tire would be in service for ten years. They were required to provided the same information, with the week and year the tire was built contained in the last three digits. The 2 digits used to identify the week a tire was manufactured immediately preceded a single digit used to identify the year.
For example, if the Tire Identification Code on a tire reads:
XXXXXXXX 0680
XXXXXXXX 0600 06 - Manufactured during the 06th week of the year
XXXXXXXX 0680 8 - Manufactured during the 8th year of the decade
While the previous serial number format identified that a tire was built in the 8th year of a decade, there was no universal identifier that confirmed which decade (tires produced in the 1990s may have a small triangle following the Tire Identification Code to identify the decade). The Tire Identification Code format used since 2000 accurately confirms the year.
And finally, hold on to your sales receipts. Most tire manufacturer's warranties cover their tires for four years from the date of purchase, or five years from the week the tires were manufactured. So if you purchase new tires that were manufactured exactly two years ago they will be covered for a total of six years (four years from the date of purchase) as long as you have your receipt. If you lose your receipt, your tires' warranty coverage will end five years from week the tire was produced (resulting in the tire manufacturer's warranty coverage ending only three years from the date of purchase in this example).
The Stock 80 uses a P-metric tire (designated by the use of a P in the size i.e. P275/70/16), with a recommended inflation pressure of 32psi. When converting to a light truck tire (LT) which most A/T and Max Traction tires are (LT is designated on the sidewall next to the size i.e. LT275/70/16), you should add approximately 10psi to the factory recommended pressures. Based on the load charts (and this doesn't matter whether you are running a C, D, or E rated tire) you should adjust your base pressure to be as follows when changing to an LT tire:
275/70/16, 265/75/16 - 42-45psi,
285/75/16, 305/70/16 - 40-42 psi,
295/75/16- 38-40psi,
315/75/16- 36-40 psi.
You should not go below the minimum pressures above. If you have a truck that has a lot of extra weight (i.e. sliders, bull bar, winch, bumpers, etc.) add 5-8psi to the above.
Tire Sizes -
We should be a little more accurate in our sizing for the faq, at least have the information out there. The actual sizes of various tires are as follows:
275/70/16- 31.2"
265/75/16- 31.8"
285/75/16- 32.8"
305/70/16- 33.0"
295/75/16- 33.2"
315/75/16- 34.6"
Note these are BFG A/T sizes, various manufactures will vary by up to .2" but are generally at the same size.
For reference traditional inch size tires measure as follows:
31x10.5 - 30.7"
32x 11.5- 31.7"
33x 12.5- 32.7"
35x 12.5- 34.7"
So when computing tire sizes, keep in mind the OEM tire is really what would be 31.5" tire under traditional sizing.
265/75/16 the tire size nobody talks about. The 265/75 gives you a split between the stock size and stepping up to a 285/75 tire. They are 1/2" taller than stock and are available in more choices than the stock size. After careful thought I have stuck with this size rather than go to 285/75 as I am unwilling to take the accleration and gas mileage penalty.
.
Understanding Tire Tread
Tread - Note BF Goodrich tires are used below for examples.
Tire tread comes in all sorts of flavors, however, when off-road performance is the focus "All Terrain Tread" and "Mud Tread" are probably best suited for the task.
Street/Performance Tires/ All season - These are typically radial tires were the only consideration is on pavement performance.
All Terrians- All Terrain tread performs well under a variety of off-highway conditions and to some extent has closed the street/trail performance gap. The closed tread design is usually quiet on the highway, yet noisier than a street tire, and performs well on rocks, sand, and on the highway. As you might expect, they tend to load up with mud, but some of the AT designs perform surprisingly well in muddy conditions. For highway driving with minimal trail use, the AT design is an excellent choice.
Mud Terrians - Mud Tires, and this may not surprise you, perform well in mud. Beyond the obvious superior performance in mud, they generally also do well on rocks and in deep snow. The MT is at its worst in rain and some can be outright dangerous in icy conditions. The performance on ice for many mud tires is due to a lack any siping and consist of large flat surfaces, ie the ends of the tread lugs. Large flat surface on ice equals no traction and greatly lessens control as well. Some mud tires however are siped in an effort to improve their performance on ice. Siping should be a deciding factor if you live in areas that get icy roads. Another possible disadvantage of the aggressive tread of the Mud Tires is that they have a tendency to be noisy, however, for the true mudder, this is hardly an issue.
Thse more aggressive Tires (May be still classified as an MTR, but are much more agressive)- Some specialized tires, like the BFG Krawler, were designed to be the leader in one category - in this case, rock crawling. This is one of the fastest growing aspects of competative offroading, and these tires reflect th eleading edge in tire technology - super sticky computer designed void pattern and specific rubber compounds designed to resist abrasion are used. Available only in selected sizes over 35", these would be ideal on a rock buggy, but not so good on the street. They are, however, street legal.
Mil-Spec Tires and Non-DOT Tires -
Micheline Mil-spec XML
Non-DOT Tires
Other Threads or articles related to Tires:
cary's thread on tire inflation
Walking Eagles Thread on C vs D tires
Landtoys thread on Gross weight and tires
Christo Slee's article on Lift size vs. Tire Size
Note- will clean up and add nice links later for the below
https://forum.ih8mud.com/showthread.p...l+narrow+tires
https://forum.ih8mud.com/showthread.p...narrow+tire s
https://forum.ih8mud.com/showthread.p...narrow+tire s
https://forum.ih8mud.com/showthread.p...ighlight=tires
https://forum.ih8mud.com/showthread.p...narrow+tire s
https://forum.ih8mud.com/showthread.p...l+narrow+tires
So which tires are right for me?
Once you have defined your current and future plans for your truck, you can then begin to wade through all the different varieties.
If your primary concern is highway performance with an ocassional off road expedition adventure, an All Terrain tire might be the ticket. If that's the case, you now have to decide which tire.
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