Hard data on 37s

RoyalT · Dec 11, 2023

This is exactly the conversation I keep having with myself lol. I currently have stock non XR wheels with 35x12.50 ridge grapplers. At first when I bought them I didn’t think about unsprung weight. Now I’m considering every option to reduce unsprung weight.

So here is my question to you guys…if I go with a wheel that weighs (22lbs) and 37x12.50 K02’s C load (64lbs) will that 22lbs of reduced unsprung weight on each corner make a significant difference even stepping up to a 2” taller tire throughout all speeds up to 120mph?

At Risk Ute · Dec 11, 2023

npgtech said:
I know this was months ago but... care to share where you found that deal?? That's a fantastic price for these tires, I can't find anything lower than $2500.

Tire Rack and Discount Tire are both selling Load Range C for $368 per tire. I’m guessing they’re shedding KO2 inventory to make way for the KO3s. My shop was able to get them down to $344 (guessing they get a volume / corporate discount). YMMV.

Nuke_1 · Dec 11, 2023

Back in the summer there were deals under 300.00 each for 37's That's when I jumped and was able to sell my 0 mi take off 315's. Just lucky to find that when I did.

Viking Jeeper · Dec 11, 2023

Nuke_1 said:
Back in the summer there were deals under 300.00 each for 37's That's when I jumped and was able to sell my 0 mi take oss 315's. Just lucky to find that when I did.

Nice! I might be making the move soon.

Viking Jeeper · Dec 11, 2023

At Risk Ute said:
Tire Rack and Discount Tire are both selling Load Range C for $368 per tire. I’m guessing they’re shedding KO2 inventory to make way for the KO3s. My shop was able to get them down to $344 (guessing they get a volume / corporate discount). YMMV.

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BF Goodrich does not even acknowledge the existence of KO3 but I have been hearing about them for a while. I think tire rack said they had just two sizes, not 35 or 37.

Tank2112 · Dec 11, 2023

Anyone tried Toyo - Open Country R/T Trail?
Nice looking tire.

MDrums · Dec 11, 2023

RoyalT said:
This is exactly the conversation I keep having with myself lol. I currently have stock non XR wheels with 35x12.50 ridge grapplers. At first when I bought them I didn’t think about unsprung weight. Now I’m considering every option to reduce unsprung weight.

So here is my question to you guys…if I go with a wheel that weighs (22lbs) and 37x12.50 K02’s C load (64lbs) will that 22lbs of reduced unsprung weight on each corner make a significant difference even stepping up to a 2” taller tire throughout all speeds up to 120mph?

BFG all terrain 315/70/17 compaired to you 37” Ridge Grapplers there is a 16.5lbs difference…. Nitto’s being heavier. Not sure what the 22lbs you mentioned is referring to….?

how many miles on the Ridge Grapplers? How are they on the highway and Offroad?

npgtech · Dec 11, 2023

At Risk Ute said:
Tire Rack and Discount Tire are both selling Load Range C for $368 per tire. I’m guessing they’re shedding KO2 inventory to make way for the KO3s. My shop was able to get them down to $344 (guessing they get a volume / corporate discount). YMMV....

Ah ok, for some reason I was thinking this was for the KM3 MTs. Still though pricing isn't too bad for ATs.

Viking Jeeper · Dec 11, 2023

MDrums said:
BFG all terrain 315/70/17 compaired to you 37” Ridge Grapplers there is a 16.5lbs difference…. Nitto’s being heavier. Not sure what the 22lbs you mentioned is referring to….?

how many miles on the Ridge Grapplers? How are they on the highway and Offroad?

I have 35 inch ridge grappler. I really like them but they are heavy! I dont take the 392 off-road so I'm considering putting them on my LJ.

4x4ready · Dec 12, 2023

My Teraflex Nomad split spokes with 37"s KOs weighed about 3-4 lbs. lighter per wheel/tire on the scale compered to my stock 2024 Wheels with 315/70R17's. Maybe makes sense since the 37's are about an inch narrower but obviously taller.

RoyalT · Dec 12, 2023

MDrums said:
BFG all terrain 315/70/17 compaired to you 37” Ridge Grapplers there is a 16.5lbs difference…. Nitto’s being heavier. Not sure what the 22lbs you mentioned is referring to….?

how many miles on the Ridge Grapplers? How are they on the highway and Offroad?

I have 35” Ridge Grapplers currently. For 35” tires they are heavy but I’ve had zero complaints out of them other than the weight factor. I have 9k miles on them so far. On the highway to me they are quiet and as far as performance off-road goes I’ve only had them out in the snow which did great with traction.

ParadigmDawg · Dec 12, 2023

RoyalT said:
I have 35” Ridge Grapplers currently. For 35” tires they are heavy but I’ve had zero complaints out of them other than the weight factor. I have 9k miles on them so far. On the highway to me they are quiet and as far as performance off-road goes I’ve only had them out in the snow which did great with traction.

I had 37 RGs on my TRX and put 35s RGs on my Wrangler since its a non-XR and came with 33s. I really like the RGs and it seems like a lot of people in my area run them.

My plan was to stay stock for a year or so but 3 weeks later, I ordered a Teraflex RT3 KIT/Falcon 3.3s/ RG 37x12.5s. I am sure I will likely need regeared after all of that which I didn't think through. My initial thought on buying a Non-XR was that I would be wasting money on a XR since I was going to change the suspension anyway. Now I wonder if that was the smart choice.

I am confused on the actual height of the XR and non-XR too. I have read that the factory height is the same, the XR is 1/2" higher, and that the XR is 2'' higher. My goal is to be the same height as the XR plus ~3.5" since the 392 I am basing everything off of, and that I really like how it looks and rides, is a XR. The owner tells me mine will be shorter since it is starting as a Non-XR. Does anyone know the true answer?

Viking Jeeper · Dec 12, 2023

ParadigmDawg said:
I had 37 RGs on my TRX and put 35s RGs on my Wrangler since its a non-XR and came with 33s. I really like the RGs and it seems like a lot of people in my area run them.

My plan was to stay stock for a year or so but 3 weeks later, I ordered a Teraflex RT3 KIT/Falcon 3.3s/ RG 37x12.5s. I am sure I will likely need regeared after all of that which I didn't think through. My initial thought on buying a Non-XR was that I would be wasting money on a XR since I was going to change the suspension anyway. Now I wonder if that was the smart choice.

I am confused on the actual height of the XR and non-XR too. I have read that the factory height is the same, the XR is 1/2" higher, and that the XR is 2'' higher. My goal is to be the same height as the XR plus ~3.5" since the 392 I am basing everything off of, and that I really like how it looks and rides, is a XR. The owner tells me mine will be shorter since it is starting as a Non-XR. Does anyone know the true answer?

Let us know how you feel with 3.73 and 37. I am very much considering 37 KO2 but assuming a re-gear comes with that. The XR is 1/2 inch higher and that is all in the tires.

ParadigmDawg · Dec 12, 2023

Viking Jeeper said:
Let us know how you feel with 3.73 and 37. I am very much considering 37 KO2 but assuming a re-gear comes with that. The XR is 1/2 inch higher and that is all in the tires.

I am going to play like the 3.73s are fine for about a year because I don't want to buy new gears right now...lol...

So when I get on here and state that it works great...don't believe me....

Jeepherz · Dec 12, 2023

Socal_392 said:
Lol. I was also worried about it. But I went with 80lb Mickey Thompson and KMC beadlocks. I can tell the difference but it’s still faster than a Jeep has any business being. But I already had 4.56 gears with the XR package.

The stock wheels, believe it or not are really heavy. I think I read the XR wheels are 41lbs. You could go to a forged lightweight wheel and shave 15lbs to offset the 3lbs of the 37’s.

Food for thought

Stop that. Just stop it.

Jeepherz · Dec 12, 2023

I do like those Nittos but the moment I picked them up at the tire place I changed my mind - this was on my JK. SO heavy. I went to MTRS to save weight. This was years ago- I think they might be a little lighter now? But I'd shop that for sure. If you don't plan to wheel there is no benefit aside from looks. And if you do wheel and they are still super heavy and MTRs are a great tire.
I was a very early adopter to re-gear on the Pentastar. I've been on probably 1000 gear threads by now. Yes the 392 is a different beastie but there is zero way I'd put on 37s with 3.73s. 475 horses or not- you're gonna feel it. Figure that $300-$400 a tire plus $1000+ for a re-gear. I am worried about slowing mine down on 4.56s and 37s.
Someone asked- the tire deals I found are all (small) local California tire shops. Sure its expensive AF to live here but there is also lots of competition so you can find deals. Found on Facebook marketplace.

ParadigmDawg · Dec 12, 2023

Jeepherz said:
I do like those Nittos but the moment I picked them up at the tire place I changed my mind - this was on my JK. SO heavy. I went to MTRS to save weight. This was years ago- I think they might be a little lighter now? But I'd shop that for sure. If you don't plan to wheel there is no benefit aside from looks. And if you do wheel and they are still super heavy and MTRs are a great tire.
I was a very early adopter to re-gear on the Pentastar. I've been on probably 1000 gear threads by now. Yes the 392 is a different beastie but there is zero way I'd put on 37s with 3.73s. 475 horses or not- you're gonna feel it. Figure that $300-$400 a tire plus $1000+ for a re-gear. I am worried about slowing mine down on 4.56s and 37s.
Someone asked- the tire deals I found are all (small) local California tire shops. Sure its expensive AF to live here but there is also lots of competition so you can find deals. Found on Facebook marketplace.

I haven't really noticed a decrease in performance going from 33'' KO2S to 35" RGs. I didn't bump this up with my Dragy but it's a Jeep so seat of the pants is plenty for me. Now going from 33s to 37s RGs, on 3.73s in my 392 will likely be a whole different story.

Not apples to apples but when I went to 37s on my TRX with 3.73, my 0-60 dropped 1/10th in 0-60.