GODZ MFG - Castle Rock, CO
Best Off-Road Wheels and Tires: All-Terrain vs. Mud-Terrain, Fitment Guide, and Stability Tips for Overland Trucks
Full Size Friday Blog: Week 8
This post will cover:
Don’t forget your rubber…
Now that I have your attention, welcome back to week 8 of Full Size Friday. This week’s discussion is, you guessed it, wheels and tires. (Come on, what else could it be?)
This week we want to cover all the intricacies of wheel and tire fitment on a properly built off road truck. We are going to start the discussion with tires since that will have a more ‘universal’ application to all readers and towards the bottom of this blog we will discuss specifics and the nerdy numbers that pertain to each manufacturer and overall fitment of the wheel itself.
All Terrain vs. Mud-Terrain Tires
Starting where the rubber meets the road, we need to discuss tires. In overlanding, we can essentially break tires into two categories, All-Terrain tires, which will perform best in ‘all’ conditions and Mud-Terrain tires, which will really reach their full potential in true off-road experiences. Now, I know, that is a pretty crude explanation of what All-Terrain and Mud-Terrain tires are ‘good’ for so let me further explain.
We’ll start with all terrain tires first since this is more than likely going to be your best option. From personal experience, all terrain tires are going to fit most driving styles better than you might think. All-Terrain tires are literally a jack of all trades. These tires tend to have a mixture of large and small lugs, an irregular tread pattern, and some sort of siping in the lugs to aid in wet driving conditions. But what does this all mean?
Tire lugs are the larger patches of rubber that protrude from the tire itself. Basically they are the ‘knobs’ as some may refer to. The lugs of the tire are designed to offer the best performance possible based on specific patterning and lug sizing that is determined by the tire manufacturer. The lugs of the tires are more commonly referred to as the ‘tire tread’ and ‘contact patch’ as the lugs are 95% of what touches the road surface and provides your grip. The area circled in red in the image below are the ‘lugs’ of the tire.
Buried within the lugs of the tires, are generally some very small, razor thin, cuts. These cuts are referred to as sipes, siping or ‘kerf.’ All-Terrain tires tend to have a lot of siping, whereas Mud-Terrain tires tend to have little to no siping. The purpose of siping is to aid in wet weather driving conditions. The sipes essentially provide micro-traction by grabbing the road surface better in wet or snowy conditions where the large lugs we just learned about tend to ice up or become too wet to provide optimal traction. Discount Tire defines tire siping as “a small slit in the tire’s tread block that creates additional tread surface area for increased grip in wet, icy and snowy conditions.” The yellow highlights in the image below are the ‘sipes’ of the tire.
I’ll step off my nerdy tire definition soapbox and get back to all terrain tires. As I previously stated, all terrain tires are going to be the go to for most of us. I personally have run these on all of my trucks including my Toyota Tacoma and now my RAM 2500, however my tire choice on these vehicles does vary. On my Tacoma, I ran 4 different sets of All-Terrain tires over my 110,000 miles with that vehicle. At first it was a 33” set of Falken Wildpeak AT3Ws, then I got a set of 33” BF Goodrich KO2s, after that I had a 34” set of Toyo AT3s and finally, I sold the truck with 37” KO2s installed. All of these tires had their pros and cons, but over my 4 years with that truck, the KO2s were my favorite by a landslide. Now that I have the RAM 2500 as my full-time overland rig, I needed to reassess my tire choice. The KO2s from BF Goodrich are phenomenal for my style of driving, but unfortunately their rubber compound is too soft for a 10,000lb truck and as such, they wear very fast in Colorado’s windy mountain roads. My RAM is equipped with the newer Mickey Thompson Baja Boss A/Ts. These tires have proven to handle snowy conditions very well and have shown good tread wear on HD trucks. Tread wear is important because at over $2,000 for a set of four 37” tires, you don’t necessarily want to be buying these every year.
That’s a lot of rambling and name dropping. So what do we want to look for? All-Terrain tires will generally be labeled as such. The BFG KO2 ALL-TERRAIN, the Mickey Thompson Baja Boss A/T, and so on. If you find yourself daily driving your truck, driving in wet or especially winter conditions, or spend a lot of time on the highway to get to your destination, I would highly recommend looking for an All-Terrain. AT tires are going to shine in all of the above conditions. The closer spacing of the lugs will help keep the tire quiet at speeds over 55mph, the siping will provide the extra bite you need in wet or snow conditions and overall, these tires tend to be a bit lighter allowing for better fuel economy as well.
Now, if you are only minutes away from your destination, if you are fortunate enough to be able to call the road/trail home, then a dedicated off-road tire in the form of a Mud-Terrain may be the better option for you. I don’t think that there is any question that a mud terrain tire will beat an all terrain tire in a true off-road scenario. Mud-Terrain tires feature larger lugs with increased spacing between those lugs and less siping, both of which result in more bite on Moab’s Slick Rock and Rausch Creek’s mud holes and mossy rocks. Now, that’s not to say you will have unlimited traction, however, in most instances, the mud terrain will do better in dedicated off road scenarios. There is a tradeoff however, if you spend a lot of time on the highway or live in a snowy or wet area, these may not be the best choice. The larger lugs and lack of siping will make the tires more noisy and will not allow you to maneuver the vehicle as well in wet conditions.
When selecting a tire, it is really important to think about your drives. Take the information above to determine whether you are better off with an All-Terrain tire or a Mud-Terrain tire. Take a look at the chart below to see some of the most popular tires in each category.
|Top All-Terrain Tire Choices||Top Mud-Terrain Tire Choices|
Determining Wheel Size
Okay, so you’ve determined what tire style is best for you, but what size should you go with? First, let’s talk about wheels, NOT RIMS….wheels.
Wheels are a dime a dozen, you can look through our site and see the KMC, Method, Icon, Black Rhino, and more all offer a host of designs, but after a while they all start to look the same. So what’s actually different and what should you be looking for?
Let me explain. Anything that we sell on our site is going to be a suitable wheel for off roading and overlanding, what your decision is really going to boil down to is sizing most importantly and then your preferred style.
On our site, we separate wheels by generation of truck so you can ensure that you are going to purchase an item that fits. Bolt pattern is going to be the first thing to look into. RAM 2500/3500 trucks use a wheel spacing of 8x165.1. This means there are 8 bolts that are spaced 165.1mm from each other when measured directly across from one another. Think of lug nuts like a clock for one minute. When you measure from 12:00 down to 6:00 or 3:00 over to 9:00, these numbers would be 165.1mm. The ‘8’ means that there are eight lug nuts within the pattern.
So, once again your RAM 2500s/3500s use an 8x165.1 bolt pattern. Ford F250s/F350s utilize an 8x170 pattern and last, but not least the Chevy and GMC 2500/3500 trucks use an 8x180mm spacing.
The Bolt pattern is only the first step of the equation, however. Once you ensure the wheel can actually bolt up to your truck, what we really need to focus on is the size of the wheel. Range Rover loves big wheels, and sports cars excel with large diameter wheels, however, our trucks don’t, well, to an extent.
To select the best size wheel, we once again need to look within. How are you using your truck? Do you travel with the truck by itself with a bed rack and roof top tent? Maybe a camper? Or did you opt to go the trailer route? Your answer to these questions will help us determine the best sizing for you.
Starting simple, let’s say your truck is equipped with a roof top tent or maybe a lightweight camper like a Go Fast or Lone Peak. In this instance, you don’t have a lot of weight to worry about and you can afford to go with a small wheel like a 17” Method 704 or 17” Icon Vehicle Dynamics Rebound HD. This smaller wheel will allow for the maximum amount of tire. But why does this matter? Well, the more sidewall you have, the more you can ‘air down’ off road, allowing for a smoother and more compliant ride. Say you put a 37” tire on your truck, you will essentially have 10” of sidewall on 17” wheel which is going to act just like a shock absorber. As you drive over different terrain, the tire will flex and compress which allows for a smoother ride both on and off road, but this may not be your best option if you have a larger camper or tow a lot.
Let’s say your setup is larger than a roof top tent or lightweight camper setup. Let’s say you have installed an Alu-Cabin or a Four Wheel Camper slide-in camper that weighs 1000+ pounds. Overall, this may not be a ton of weight on the truck, but it can still influence wheel size. With a larger load such as this, you could still get away with a 17” wheel with the proper load ratings. However, to eliminate or reduce tire ‘wag’ you may want to consider jumping up to something like an 18” wheel. Jumping up to a larger wheel will reduce the amount of sidewall you have. A smaller sidewall means two things, one, your tire will be slightly ‘harsher’ as you don’t have as much "cushin’ for the pushin'," but what it does mean as you will have more stability on the highway as you haul a larger, more top heavy load on mountain passes and windy highways.
This same principle applies to towing. If you're going to be towing a lot with your offroad vehicle a larger wheel will serve you well. Maybe you work landscaping and use your truck to haul a dump trailer during the week, but still like to play on the weekend, or maybe you have a sweet Black Series Trailer that comes with you on your annual desert trip. Regardless of what you’re pulling, an 18” or even a purpose built 20” off road wheel will be your best option. Again, bigger wheel, less tire, more stability. This is especially important with heavy trailers as the flex in your tire will be increased the smaller your wheel is. If your tire is flexing all over the place, this can make your towing unpredictable and potentially dangerous.
Look at the long term build goal for your truck and select a proper diameter wheel for that adventure.
Wheel Backspacing and Offset
The last measurement we want to look at is wheel width and backspacing. Wheel width is semi-relative to the wheel diameter, but most wheels will be between 8” and 9.5”. The width is not as important as the backspacing.
Backspacing is a little tricky to explain so insert picture here:
Using the image above, we can begin to understand backspacing a little better. Back spacing is essentially the measurement of how far your wheel will or will not protrude into the wheel well. A 0" backspacing would mean that the inside lip of the wheel is even with the mounting surface on the vehicles rotor. Whereas a 5.75" backspacing would mean that the wheels inside lip sits 5.75" into the wheel well from the mounting surface on the rotor.
For most full size trucks in the off road realm, we want to look at wheels between 4.5" and 6" of backspacing. Vehicles like the RAM trucks excel with 5.5" to 5.75" of backspacing.
How does backspacing correlate to offset? Offset is the measurement from the center of the rim to the face of the mounting surface. Two wheels with the same backspacing can have a different offset simply based on rim width. Sticking between +20mm backspacing and -20mm backspacing will be the sweet spot on most vehicles. +20 backspacing will sit about 1.75" further in the wheel well when compared to a wheel with -20mm backspacing.
I realize this has been a very long and dense week of Full Size Friday, if you made it this far, congrats! If you still have questions, contact us, we would be happy to help steer you in the the right direction.
So in conclusion, wheels and tires have a ton of options. Your order of operation in selecting the right option is as follows.
- Determine how your truck will be loaded and what type of driving you will be doing. Pick a tire that suits you, All-Terrain vs. Mud-Terrain.
- Determine what wheel size is best. The less constant load on your truck, the smaller the wheel you can get away with. If you have a heavy constant load or tow a lot get a bigger wheel.
- Pick a wheel with an appropriate diameter, then look at wheels that have a suitable backspacing and offset.
- Lastly, go back to selecting the tire size that matches your wheel selection and get those suckers mounted!
- Oh, and don't for get your new lug nuts, most aftermarket wheels do not reuse OEM lug nuts.
Thanks for reading! Next week we will chat about Bed Racks, Tents and Campers!