40” on Steel or 37” on KMC

phillypete

phillypete

New member
I am in the process of a axle swap which will require 8x6.5 wheels.

As I am working through the budget I noticed that some cheap steel beadlocks wheels and 40” tires (Cooper STt Pro) is about the same as a set of KCM Machetes and 37” tires.

My question is which combinationwill give the best results both offroad and on-road. Obviously the extra ground clearance of 40s is nice but what would I be giving up going with the steel wheels?
 
phillypete said:
I am in the process of a axle swap which will require 8x6.5 wheels.

As I am working through the budget I noticed that some cheap steel beadlocks wheels and 40” tires (Cooper STt Pro) is about the same as a set of KCM Machetes and 37” tires.

My question is which combinationwill give the best results both offroad and on-road. Obviously the extra ground clearance of 40s is nice but what would I be giving up going with the steel wheels?
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No cheap steel beadlock I have ever seen has a ring as thick or as strong as what a KMC Machete has nor does it have bolts that are as big.
 
wayoflife said:
No cheap steel beadlock I have ever seen has a ring as thick or as strong as what a KMC Machete has nor does it have bolts that are as big.
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I understand the cheapo beadlocks are a significant downgrade from those smokin hot KMCs, but I also understand 40s are a lot better than 37s. So what’s the better trade off; cheap wheels and big tires, or small tires and nice wheels.
 
Honestly, that's a question only you can answer. Are you more interested in the appearance of your Jeep or the functionality? Are you looking for a wheel that is going to take a beating from rocks and other trail obstacles and not leave you stranded because of failure? Where do you wheel? Mud? Rocks? Proper wheel and tire selection is all about how you specifically intend to use your Jeep. Also, a good set of 37's with a good suspension setup and lockers can go just as far as 40's if you know how to drive and pick the right lines.

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You say you are doing an axle swap that will require use of 8x6.5 wheels. It seems like a fair assumption that you are going to 60s. Maybe ask yourself why you elected that course, and then evaluate how your reasoning impacts the choice between (a) going to 40s in cheapo steel wheels, (b) going with (presumably staying with) 37s on nice wheels, or (c) just dropping more money to go whole hog with 40s and nice wheels. If your original rationale for going to 60s was so you can run 40s, then you can eliminate option b.
 
phillypete said:
I understand the cheapo beadlocks are a significant downgrade from those smokin hot KMCs, but I also understand 40s are a lot better than 37s. So what’s the better trade off; cheap wheels and big tires, or small tires and nice wheels.
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Why are 40’s better than 37’s. Is it a dick measuring contest?


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OverlanderJK said:
Why are 40’s better than 37’s. Is it a dick measuring contest?


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If it is I better go with the 42s because I have some compensation to get doing.

That being said:

Why are 35s better than 33s.

Axle clearance, larger rolling circumference... the benefits of larger tires are obvious, so I suppose the crux of the discussion is the merits of a $400 beadlock vs a $200 beadlock.
 
phillypete said:
If it is I better go with the 42s because I have some compensation to get doing.

That being said:

Why are 35s better than 33s.

Axle clearance, larger rolling circumference... the benefits of larger tires are obvious, so I suppose the crux of the discussion is the merits of a $400 beadlock vs a $200 beadlock.
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From what I've seen, 42's are actually too big for a JK. If they were in fact better, I'd be running them.

37's are actually what I'd consider to be a perfect size for a JK. Sure, I run 40's now but I wouldn't hesitate to run 37's.
 
fiend said:
You say you are doing an axle swap that will require use of 8x6.5 wheels. It seems like a fair assumption that you are going to 60s. Maybe ask yourself why you elected that course, and then evaluate how your reasoning impacts the choice between (a) going to 40s in cheapo steel wheels, (b) going with (presumably staying with) 37s on nice wheels, or (c) just dropping more money to go whole hog with 40s and nice wheels. If your original rationale for going to 60s was so you can run 40s, then you can eliminate option b.
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I am doing a D60/14b swap. I walked into a great deal on the axles, and I figured it would make a great father/son project. I started looking at axles because I’ve struggled with 3.21 gear far too long and I wasn’t going spend a dime on that D30 stock front axle.

So it started off as re-gear and lockers. Which then imidiately turned to crate D44 and re-gear/locker the rear. Which turned into 44/60 crate axles after hearing the estimates on labor. Which is about when this D60/14b thing came together.

I don’t have a philosophy or specific requirements for my jeep build. I go where the Jeep allows and don’t try to make it go where it won’t. My goal when I wheel is to hang with my friends and drive it out like I drove it in.

I never really saw 40’s in my future, but now that my axle plans have changed it has got me thinking of bigger tires.
 
phillypete said:
I am doing a D60/14b swap. I walked into a great deal on the axles, and I figured it would make a great father/son project. I started looking at axles because I’ve struggled with 3.21 gear far too long and I wasn’t going spend a dime on that D30 stock front axle.

So it started off as re-gear and lockers. Which then imidiately turned to crate D44 and re-gear/locker the rear. Which turned into 44/60 crate axles after hearing the estimates on labor. Which is about when this D60/14b thing came together.

I don’t have a philosophy or specific requirements for my jeep build. I go where the Jeep allows and don’t try to make it go where it won’t. My goal when I wheel is to hang with my friends and drive it out like I drove it in.

I never really saw 40’s in my future, but now that my axle plans have changed it has got me thinking of bigger tires.
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Yep. The Jeep snowball. I understand. [emoji23]

As has been noted, 37s are a good size for a JKU. But if you’re going all in, maybe go straight to 40s and have no regrets.
 
I’d honestly say go for 37’s and kmc. Wheel it for a while, get comfortable. Then when your 37’s are worn you can jump up if you still feel the need. If you buy 40’s and steelies now then you’ll eventually (probably) want better wheels, possibly around the time of new tires. So essentially you’d be spending the money on wheels and tires twice, where you could do 37’s and kmc’s now and only buy tires routinely when they need to be replaced and eventually end up on 40’s


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Start with the 37’s on KMC and if you want to move up you always can. At least you’ll have a good set of wheels to put 40’s on if that’s what you decide later.


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I have 37s, and the majority of the guys I wheel with have 40s. AND 1 guy with 42s on a JKU

they pick their line, they make it up, I pick my line, I make it up.

I've never once been somewhere where I needed to pull cable and all of them didn't... If I have to pull cable, its likely that a good handful of them had to pull cable as well. I'm happy with my 37s. :thumb:

Sure, 40s are bigger, but Unless you are running the biggest ledges, and the largest bolders ALL THE TIME, the 37s will get you there just fine. :twocents:
 
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DWiggles said:
I have 37s, and the majority of the guys I wheel with have 40s. AND 1 guy with 42s on a JKU

they pick their line, they make it up, I pick my line, I make it up.

I've never once been somewhere where I needed to pull cable and all of them didn't... If I have to pull cable, its likely that a good handful of them had to pull cable as well. I'm happy with my 37s. :thumb:

Sure, 40s are bigger, but Unless you are running the biggest ledges, and the largest bolders ALL THE TIME, the 37s will get you there just fine. :twocents:
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Your friends need to learn how to wheel then... lmao jk.

OP, where do you live? I used to run 37s and was completely happy. All my buddies had 42s. I eventually got to point that I couldnt keep up. I was pulling cable all the time when they weren't. After one wheeling trip my wife told me I needed to upgrade to keep up. So of course I didnt say no, I just did it. So now when we go on our once or twice a year bigger trip at harder places I am very happy as I can do all the things I want to and keep up. The other 90% of the time I am bored silly living in Michigan. They are just too big. I picked up a set of 37s this winter just to add fun back in locally. This is why I ask where you live. If it's not near, or you dont do, really challenging wheeling it will make it boring.

Now if you do, there is nothing wrong per say with a set of steel beadlocks. The KMCs do have pluses. But i know lots of folks who run steel ones and they have been fine. I've even seen them beat them back into shape with hammer / weld them.

In the end it all comes down to how you use your jeep. Or if u want the look. If you arent shaving the 14b you are gonna have a boat anchor back there on 37s.

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I’d say go with the 40s simply because the 14 bolt is HUGE and hangs low. Or you need to shave with 37s. Like 13_gecko_rubi said, you’ll have a boat anchor. That was one of the reasons I went with the superduty 10.5 sterling rear end. It’s a little bit less strong than the 14b, but it’s strong enough for me without sacrificing the clearance.


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I-Eat-Mud said:
I’d say go with the 40s simply because the 14 bolt is HUGE and hangs low. Or you need to shave with 37s. Like 13_gecko_rubi said, you’ll have a boat anchor. That was one of the reasons I went with the superduty 10.5 sterling rear end. It’s a little bit less strong than the 14b, but it’s strong enough for me without sacrificing the clearance.


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What did you do to get around the gas tank clearance issue with the offset pinion?


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