5th Gen 4Runner BF Goodrich Ko2 A/T Tires (285/70R17) Complete Review and Overview
This is a review of the BF Goodrich Ko2 A/T Tires. Prior to installing these, I was running the stock Dunlop GrandTreks on my 2017 Toyota 4Runner Trd Premium. I was looking for a tire upgrade since I needed something with a better tread pattern and a much stronger sidewall.
This is an overview and general review of the BF Goodrich Ko2 A/T Tires, wrapped around stock tires. If you are considering an aftermarket tire, this is a good option for aftermarket all-terrain tires.
BFGoodrich Ko2 Specs
- ALL-TERRAIN T/A KO2 – SIZE: LT285/70R17 E-LOAD
- Amazon.com (285/70R17): Check Price
- Max Load: 3195 lbs
- Max Inflation: 80 psi
- Tread Depth: 15/32″
- Tire Weight: 58 lbs
- Made in the USA
Before and After – Dunlop GrandTreks Vs Bf Goodrich Ko2s
Before: 265/70/17 Dunlop GrandTreks on stock suspension
After: 285/70/17 Bf Goodrich Ko2s on Icon Stage 2s
Here is a picture of my stock vehicle on the 265/70/17 Dunlop GrandTreks on stock suspensions vs 285/70/17 Bf Goodrich Ko2s on Icon Stage 2s.
Thinner Side-Wall 265/70/17 Dunlops
Below is a picture of the stock Dunlop Grantreks which are 265/70/17. You can see the thinner side walls.
The picture below is the newly upgraded Bf Goodrich Ko2s at 285/70/17.
The first thing I did before upgrading my tires was getting a lift. There is quite a lot of information out there in regards to lifting your 4Runner vs tire size.
For smaller tires, you can get away with a small leveling kit without clearance issues. If you are looking for the biggest tire size on your 4Runner, then you should reconsider the question and automatically level up with a lift kit or leveling kit.
If you do go with larger tire size, then you will need to read the guide on fitting bigger tires on your 4Runner.
Once I got my Icon Stage 2 Suspension Lift, I headed off to Discount Tire in Las Vegas to check out what tire options they had. I also got some advice from Brenan @Trail4Runner to see what are popular tire brands and sizes. The options I had for size were either 275/70/17, 285/70/17, 285 /75/17.
With the smaller tires, you can go with C load rating and with the bigger tires, you got E load rating with a 3 ply sidewall. The main difference between C load and E load is the tow rating and the polyester cord sidewall. There is also a small weight difference between the two as well.
There are many popular tire brands such as Nitto, Toyo, Cooper, and Dunlop to name a few. I settled on the BF Goodrich due to its pricing, popularity, and availability. The Ko2s are one of the most popular all-terrain tires for the 4Runner, on-road performance, and off-road performance.
There are armies of 4Runners running the Ko2s as well so you can fall back on support if you need any. You can’t go wrong with bigger tires so I chose the biggest I could get without rubbing and a body mount chop which is 285/70/17. The 285 makes the tire flush against the fender with the extra width.
I didn’t go with 34s due to the potential of rubbing and I did not want to deal with any body modification. The Ko2s cost me around $1,000 after tax and warranty from Discount Tires.
On-Road and Off-Road Review
The 285s were definitely a bigger tire and you can feel it both on-road and off-road. The tire weighs in at 58 pounds each and you will immediately see power loss from the line. There is also a big drop in MPG with bigger tires. I am running stock rims, sliders, and skids and my MPG is around 14.8 on average.
The larger all-terrain tires definitely gave the truck a more rugged look as opposed to the stock tires. In my opinion, Toyota should have included all-terrain tires for all of their off-road packaged vehicles. They do include options on some 4Runners with the Nittos but not all of them. All-Terrain tires should be standard on all off-road, or Pro models of the 4Runner.
The first place off-road I took to test the tires were Bitter Springs trail near Northern Las Vegas. It is a 30-mile trail with a trail rating of around 2. The larger tires mixed with my Icon shocks handled the roads effortlessly while aired down to 17 psi.
There were some smaller rock gardens on the trail as well and the Ko2s handled it perfectly. There was no rubbing on surface roads nor in full reverse. The only rubbing I had was during off road when the wheels are tucked in, but it was quite minimal. I do not do any extreme trails nor rock crawling so I could not provide any feedback under harsher conditions. Some pictures of the trail. My car is raised 2 inches with Icon Stage 2s.
Here is a picture of the South Callville Bay Trail
I am definitely glad I went with the larger size tires due to the increase in the surface area it provides during off-roading. The road noise was minimal and not noticeable. My only issue was the power loss and gas mileage, but that is to be expected with the increase in weight and negligible when wheeling.
great information, thank you. I already completed a lift kit install, ironman 4X4 FCP kit, 3″ front and 2″rear with new UCA and rear adjustable panhard bars and rear adjustable sway bar links. Also added front diff drop from toytec. Still waiting for new set of wheels with 0 offset and BF KO2 285/70/R17. Aready see a big impact on the mpg just with the lift. once i complete the wheel/tires and front bumper and skid plates, not sure what the final mpg will be, but that the hard part and sacrifice for a better off road rig. once all the mods are completed, i will see if i need to adjust the front suspension 1/2 or a inch….Fun ride, be safe.
Hi William. I have a 2018 4Runner with a 2.5″ Toytec lift. I was planning on buying the K02’s sized at 285/70/17. But, after your review I am wondering if I should just go with the 275’s instead. I do a lot of extreme off-roading in the desert areas that are very remote, so I need dependable tires. But, I also drive long distances on the highway as I live in a small town near Death Valley. You mentioned you had some rubbing, and I am concerned I may have the same issue. My husband wants the larger size, but I am the one that will be driving it off-road. Thanks in advance for your help!
I run that same size tire on my 2016 SR5 with Bilstein 2.5 lift and haven’t had any trouble rubbing except in reverse for the first few months of use and when the shop had over inflated the tires. That has really not been an issue and I have not modified the body or mud flap.
Breaking down may be your issue, however what difference does it make if your vehicle was not designed to do what your trying to do,period.Lets not get in a wee wee contest over Jeeps vs. Toys. You can’t make a silk purse out of a pigs ear. A Jeep by design is different then a Toy suv- period. A 1/2 ton pick up is different by design than a Lexus sedan. The p/u may break down, but it is doing what it was made for. The Lexus IS still a Lexus & will never be a truck. So stop trying to be an automotive engineer. Your knowledge is limited, you admit your ideas did not work because it rubs. So you failed in your limited modification. Your Toy will also fail if your dumb enough to think you can make it into a Jeep. Or perhaps you should use your knowledge to start your own car company & we can judge you by your success or failure. I don’t see many Toys threatening Jeep sales or vise Bertha.
I’m not trying to out jeep a jeep, I am trying to get the best traction for my on road and off-road applications. If I wanted to smash your jeep I’d dump a few grand into a samurai and call it a day.
Lol, that’s cute. I’d rather not break down on the trail, I’ll stick with my Toyota.
Weight & tire size both effect performance-period. Now the real issue.Your Toy was not designed for that tire size(it rubs). The engineers know what they are doing. All the lift kits& other after market crap is simply a small improvement. It’s a trade off,& you lose more than you gain.If spending big $$ to make you feel good-great. It kills your resale value,etc, etc, etc. Your Toy is a great vehicle for what it was designed for. Simply put, if you want a off road vehicle spend your money up front.,buy a go anywhere,any place a sane person wants to go vehicle. It’s called a Jeep. In stock form it will do everything if your sane. Enough said. Toys=mall crawler.
Lol why are you on a 4runner website crying about what other people do to their rigs? I just imagine a little kid’s voice whining “Jeeps are better!! “ go to a Jeep forum or site and cry about toyota, not on here. You act like toyota owners are the only ones who lift their trucks and put big tires on them. Lollll come on bro. Grow up and get a life. People do what they want to their rigs with their own money.
If your such a Jeep fan and do not like Toyotas why are you on this website in the first place?
Matt, Thanks for responding. The relation for the Equivalent Mass of the vehicle taking into account the rotational inertia, Meq = Mv*(1 + 2*Mw/Mv), shows that the Equivalent Mass, Meq, of the vehicle is GREATER than the static mass, Mv. The factor 2*Mw/Mv is the contribution due to the rotational inertia of 4 wheels. That analysis, however, assumes wheel diameters don’t change, just mass.
The numbers I used, however, is flawed, because Mw did not take into account the tires PLUS wheels, my bad! I was too lazy to to go back and correct that. With corrections to the numbers used, it should show the difference between two tires would be less because the difference in Mw (the total mass of wheel and tire) for two different tires on the same wheel would be less. Of course the interesting case would be going with a more robust (heavier) tire and try to counteract its effect by going to lighter wheels. Yet if the more robust tire has a larger diameter, you would not be escaping the effect changing the final drive ratio and also making the brakes work harder. As usual the devil is in the details.
“The tire weighs in at 58 pounds each and you will immediately see power loss from the line.” I see this time and time again as the reason why bigger tires kill gas mileage. No! It’s the gearing based on ratios of diameter that matters more than the weight of the tires.
Everyone knows that Force = Mass * Acceleration. Or Acceleration = Force/Mass. A simple analysis equivalent to undergraduate dynamics class showed that the effective mass of a vehicle that includes the effect of spinning up the tires is Meq = Mv*(1 + 2*Mw/Mv) where Mv is the mass of the vehicle with its tires, and Mw is the mass of each wheel.
If we assume a vehicle weight with stock tires to be, say, 4000 lbs and (from 4R spec’s) the weights of the 265/70 Dunlop Grandtrek A20 and 285/70 KO2 weight are 39 and 58 lbs from specification sheets for both tires. The effective masses of stock (bigger tire are 4000*(1+2*39/4000) = 4,078 lbs and (4019)*(1 + 2*58/4019) = 4,135 lbs which is a difference of 1.4%
A bigger change comes from the decrease in the overall gear ratio by the ratio of the tire diameters. That ratio is 32.8″/31.7″ or 3.5% difference, which translates to that amount of lower acceleration, i.e. 2.6 times as much of an effect as the increase in weight of the tires.
The effect of gearing when comparing different sizes of say KO2’s would be even more pronounced compared to this analysis of going from a relatively light P-duty tire to a much heavier E-rated KO2. See for yourself with a KO2 LT265/70R17/E, 53 lbs, 31.7″. The answer should be effective mass 4000*(1+2*53/4000) = 4106 lbs compared to 4005(1+2*58/4005) = 4121 or .37% . The ratio of diameters is the same, 2.7% higher gearing. Now the effect on acceleration due to size is over 7 times that due to weight. Check my numbers and let me know if I messed up somewhere!
You’re using static weight when you should be rotational inertia. http://hpwizard.com/rotational-inertia.html
Hey Matty, I lifted my 2.5 all around using factory specs. It didn’t pose any issues after these months of having it. I love these tires! I took it into some sand dunes and crawled up a hill effortlessly with the 285s while some of the others who had 265s had issues.
If this isn’t your daily driver I would go for a C load rating and maybe 275s instead. The 285s are really heavy and it killed a easily 2 mpg. Mine isnt a daily driver so I could bear with the loss of speed and mpg.
I read that you went with the Icon Stage 2 lift kit. Since this suspension is adjustable and because it is factory set at 2.5inches, I was wondering how high lifted your vehicle in the front? Thank you. Im glad someone finally wrote a review on the BFG’s on here.
My understanding is the KO2s are severe snow rated. As such, I plan to use them as snow tires here in Oregon, rather than spending $1200 on a dedicated set of snow tires and steel wheels.
I’m planning to go with the same size as is currently on my ’17 SR5 4runner, as soon as I kill the AT20s – which have actually been better than I expected. For me, LR E is overkill, so we’ll go with LR C and get a bit better mileage
Thanks for the review. I have a 2017 with the stock tires and considering these as a replacement. Looks like they will do a lot better in snow than the stock tires.
Great site by the way!
Thanks for the info. I’m on the same journey as far as new wheels and tires. Not to mention a lift kit first. Your feedback is really appreciated.