35" KO2s vs 33" KO3s or...

[GroovyGeek]

My 33" KO2s are around 10kmi from the graveyard and I have started contemplating my choices.

The new KO3s are supposedly better wet than the KO2s but most of my driving is around the desert SW so wet traction is not that important.

BFG has made the KO3s meaningfully heavier than the KO2s so a 35" KO2 weighs as much as a 33" KO3.

MPG is important to me, the BD is also a DD. I currently get 18.8 mpg city driving a d don't have any interest in dropping below 18.

I don't go routinely on challenging trails, but a couple of times a year I end up on 4 and 5 rates trails, so I would like to retain good sidewall strength.

With all that, I am thinking the following ranking

1/ Replace with another set of 33" KO2s. If it ain't broken don't fix it

2/ Go for the 35" KO2s. I am on a 2" lift so this will fill out the wheel wells better and give me another inch of ground clearance, while preserving the off-road performance. MPG likely to get closer to 18 and maybe high 17s.

3/ Don't be a Luddite, get the 33" KO3s. Will come in handy the few times I go to the East Sierras every winter, but beyond that I don't expect much difference in handling. MPG should be the same as the 35" KO2s

4/ Or....? I am all ears for suggestions.

With all this in mind,

Sponsored

 

[IwannaGOfast]

Since you have the time, keep searching for a set of f150 raptor take offs from offer up. They are listed all the time, but find the right private seller (not someone with hundreds of tire listings). I ended up finding such a good deal on 5 new tires, I couldn't even consider buying a different tire.

I also have always loved the BFG a/t. I've had multiple sets of KO's and KO2's over the years.

 

[GroovyGeek]

The F150 raptor OEM tires are 315/70-17 C2 rated right?

 

[nolimits]

If MPG’s are your main concern than any 35 is going to disappoint you. It’s not just weight but also larger diameter that changes your leverage/gearing effect and creates more strain to get rolling.

Sure, a lighter 35 will do better than a heavier one but you still get dinged for diameter increase (aka rotational mass).

FWIW….

Stock 33” KO2’s = 50#
Stock 35” GY’s = 55#

Weight wise, the stock GY’s are hard to match. My experience with wheels and tires is you generally sacrifice in one area to excel in another. You need to evaluate what is most important to you. If MPG’s is really it, then physics apply and you lose MPG’s no matter the 35 you choose.

My question back to you would be does the decrease in MPG make a meaningful difference to your life & budget? Most people drive 10-15k per year. Even losing 3mpg has minor effects, at least IMO.

15k / 18mpg = 834 gallons/year
15k / 15mpg = 1000 gallons/year
1,000 - 834 = 166 x $3.50 = $581/yr or $49/mo

 

[Brian_B]

I think @nolimits is correct - you will lose MPG no matter what 35 you go with. Just a bigger diameter to roll around.

I do see people with SAS's getting decent mileage, but they also have the 4.70 gearing to help with those bigger tires. Not sure what engine/gearing you have (and also not saying you can't run 35's without the 4.70 or on the 2.3) - but taller gears and the smaller 4cyl get impacted more by bigger tires - not as much torque to put to them.

The lightest / more fuel efficient 35 I've seen is the SAS takeoff - the GY Territories at 315/70R17 (same one nolimits mentions).

What your mileage would drop to? I couldn't say off hand, mileage depends on a ton of different things. Just would bet if the only thing you change is going up from 33 to 35, that it would go down some amount, and there's every possibility it ~could~ drop below your 18 target.

My thought (I stole this from @mpeugeot) - look for a set of SAS takeoffs. Get the wheels/tires together. That gives you a an entire second set you can swap between in your garage. That will also be the GY Territories, and you can slap them on and see what it does to mileage.

If it's acceptable, you can sell your old ones off (even with worn rubber you'll get a little bit out of them for the wheels and TPMS sensors). If it's not - you can get new rubber on your old rims, and either keep the SAS takeoffs and just switch to them for trails, or flip them and get your money back.

 

[nolimits]

All good points by @Brian_B.

I might add to restore a little bit of the loss you could get the Ford ProCal tuner. That will allow you to change your tire size so the computer adjusts your shifts, speedometer, etc. Also you normally get some small performance gains.

The tuner isn’t a fix for gearing but more of a bandaid. As noted, depending what you have now the effects may be more or less noticeable.

When buying I drove 2 Badlands back to back. The first had SAS and I really liked it. Then I drove the non-SAS Badlands. I immediately felt a difference in acceleration, etc. I didn’t expect this. Both were near identical and had the 2.7 with auto meaning the SAS has 4.70’s and the regular had 4.46’s. In the end I chose the non-SAS but primarily because I found it a better value. Ford is wonky in the fact SAS makes sense in literally every model but the Badlands, at least IMO.

A final thought, if you get some SAS wheel & tire takeoffs as mentioned, be aware there is a weight gain with the wheels also. Not sure what you are running currently but my stock non-SAS wheels around 28# and the SAS wheels with beauty rings are 34-35#. They will be a few pounds more if you go true beadlocks. So without considering diameter, there is a +11# weight gain per corner using my setup as a comparison.

 

[1st 75th ranger]

My 33" KO2s are around 10kmi from the graveyard and I have started contemplating my choices.

The new KO3s are supposedly better wet than the KO2s but most of my driving is around the desert SW so wet traction is not that important.

BFG has made the KO3s meaningfully heavier than the KO2s so a 35" KO2 weighs as much as a 33" KO3.

MPG is important to me, the BD is also a DD. I currently get 18.8 mpg city driving a d don't have any interest in dropping below 18.

I don't go routinely on challenging trails, but a couple of times a year I end up on 4 and 5 rates trails, so I would like to retain good sidewall strength.

With all that, I am thinking the following ranking

1/ Replace with another set of 33" KO2s. If it ain't broken don't fix it

2/ Go for the 35" KO2s. I am on a 2" lift so this will fill out the wheel wells better and give me another inch of ground clearance, while preserving the off-road performance. MPG likely to get closer to 18 and maybe high 17s.

3/ Don't be a Luddite, get the 33" KO3s. Will come in handy the few times I go to the East Sierras every winter, but beyond that I don't expect much difference in handling. MPG should be the same as the 35" KO2s

4/ Or....? I am all ears for suggestions.

With all this in mind,

you could go taller thinner getting the best of both worlds with no rub issues for your driving habits and zone
kos2 were great in fl but when i moved to jn they were a bit
slippery i use falkin at4 now in winter and verstyre mtx in summer

 

[Fmuguira]

A 35x10.50 might be a good solution. Again watch its weight

 

[mpeugeot]

As a data point for others:

I have 315/70R17 (E rated KO2's) on my 2021 2.7 Bronco with 4.27 gears and I am still getting about 19 mpg on the highway @ 35 psi (mounted on the RTR Tech 6 17x9 +30 offset wheel).

I was expecting worse mpg and actually they get the same mileage or better than the stock Black Diamond wheels (steelies with General Grabbers) or the Milestar Patagonia M/T 295/70R17's (E rated 33.5") on the RTR Tech 6 17x9 rims.

 

[BoverW]

As a data point for others:

I have 315/70R17 (E rated KO2's) on my 2021 2.7 Bronco with 4.27 gears and I am still getting about 19 mpg on the highway @ 35 psi (mounted on the RTR Tech 6 17x9 +30 offset wheel).

I was expecting worse mpg and actually they get the same mileage or better than the stock Black Diamond wheels (steelies with General Grabbers) or the Milestar Patagonia M/T 295/70R17's (E rated 33.5") on the RTR Tech 6 17x9 rims.

Second this.
RTR 0mm offset + 315/70/17 LR: E = 19+ mpg.

Since you have the time, keep searching for a set of f150 raptor take offs from offer up. They are listed all the time, but find the right private seller (not someone with hundreds of tire listings). I ended up finding such a good deal on 5 new tires, I couldn't even consider buying a different tire.

I also have always loved the BFG a/t. I've had multiple sets of KO's and KO2's over the years.

I have a concern about the KO2 takeoff. KO2 is hard to balance. At least for me, I need to rebalance every 5k. It means 10 times in 50K lifespan. IF you add this to the total cost, it could be more than buying from Discount Tire. (e.g. Now KO2 315/70/17 c load is 270 per tire. E load can be found around 200 last year and you can request price match.)

 

[IwannaGOfast]

I have a concern about the KO2 takeoff. KO2 is hard to balance. At least for me, I need to rebalance every 5k. It means 10 times in 50K lifespan. IF you add this to the total cost, it could be more than buying from Discount Tire. (e.g. Now KO2 315/70/17 c load is 270 per tire. E load can be found around 200 last year and you can request price match.)

From what I have researched it seems that the factory tires have been pretty good about balancing. It's when they buy replacements that people have had trouble.

Apparently it's a fairly common issue people complain about. Thus far I have not had any trouble balancing mine, or excessive amount of weights.

 

[BoverW]

From what I have researched it seems that the factory tires have been pretty good about balancing. It's when they buy replacements that people have had trouble.

Apparently it's a fairly common issue people complain about. Thus far I have not had any trouble balancing mine, or excessive amount of weights.

Good to hear. In my case, it is a replacement and I can get it balanced. But after 5K or so, I need to rebalance it again.

What is a 'reasonable' price for a set of Raptor takeoff?

 

[GroovyGeek]

Yes, one of my factory ko2s seems to have a healthy block of weights on it (I am guessing 6+). What is considered excessive?

 

[SASQTCH]

You might look at the 285/70/17 (33") Mickey Thompson Baja Boss. It's an SL rated tire, but it's a 49lb tire that is an A/T. I have them on my F150 and love them. I just put a set of the 285s on my wife's Bronco.

 

[BrentC]

You might look at the 285/70/17 (33") Mickey Thompson Baja Boss. It's an SL rated tire, but it's a 49lb tire that is an A/T. I have them on my F150 and love them. I just put a set of the 285s on my wife's Bronco.

I’m in Moab right now and just replaced my stock 33” KO2s with the Mickey Thompson Baja Boss AT “pizza cutters” in 255/85R17 (35” diameter). Couldn’t be happier. They do not rub at full flex with the crash bars in (1” lift in front) and I’ve noticed a significant improvement in both clearance and the ease of rollover with the larger tire circumference.

They do not look that narrow either, due to the heavy side lugs on the tires. And science says the narrower tires actually perform better than wide tires at lower inflations. Google that subject for some great studies.

I have a throttle commander on the 2.3l manual and I adjusted the sensitivity so there’s no noticeable difference in throttle response.

All in all, I’m officially converted to the pizza cutters on the non-SAS Badlands.

Sponsored