37s with a 4 inch lift


h.gibz

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I know this question has probably been asked a million times but can I run 37s with a 4 inch lift? I am currently running tube fenders in the rear and high lines in the front.
 

Jerry Bransford

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4" is typical for 33" tires, 5" for 35's. What axles are you running? The TJ never came with any axles capable of running 37" tires and not breaking or at least not lasting very long. The biggest tire size I'd run on a Wrangler TJ with any axles the factory ever installed would be 35's. Nope, there's no way to beef up any of the factory axles to be strong enough for 37's.
 

Alex01

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I know this question has probably been asked a million times but can I run 37s with a 4 inch lift? I am currently running tube fenders in the rear and high lines in the front.
Check your bump stops and make sure you're not crushing your fenders. Long term reliability will be the real question. A few here run 37's on stock axles, not stock internals, and have faired alright.

What kind of trails do you typically find yourself on?
 

Chris

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You can run 38s with no lift, so I would say 37s with a 4" lift is an easy thing to do!



But just be aware, you'll need one of @mrblaine's big brake kits to stop it ;)

Make a YouTube video about it and then ask Blaine if he'll sponsor you... just so we can see his response :LOL:
 

Alex01

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In all seriousness though, this is a question of "can you" versus "should you".

Can you run 37s with a 4 inch lift? Absolutely.

Should you run 37s with a 4 inch lift? Absolutely not.
What size lift then? ;)

Let's hold off and assuming everything will explode until we know the trails, if any, he goes on.
 

Chris

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What size lift then? ;)

Let's hold off and assuming everything will explode until we know the trails, if any, he goes on.
What size lift? How about 5" of lift, highlines, coilovers, Dana 60s, and then some :LOL:

But even if he only takes it on-road, with 37s and a 4" lift, what is the up-travel at that point? You'll have to have so much bump stop just to keep the tires from hitting the fenders that even on-road driving will suffer.
 

toximus

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My red LJ is has 37s on the equivalent to a 4" lift. It works great and I wouldn't go any more. But you need to keep in mind that there's a ton of supporting work that needs to be done.
 

jjvw

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What size lift then? ;)
...
I could make it work on 4" spring, 1.25" body, highlines and more body trimming. I still wouldn't want to run 37s on stock width axles and wheelbase. Nevermind the problem with keeping the ball joints from falling out. But I'm also looking for more than just making a certain tire size roll down the street.
 

Chris

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Let's also not forget the factory wheelbase on a TJ probably isn't all that ideal for 37s either. An Unlimited is another story.
 

Alex01

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What size lift? How about 5" of lift, highlines, coilovers, Dana 60s, and then some :LOL:

But even if he only takes it on-road, with 37s and a 4" lift, what is the up-travel at that point? You'll have to have so much bump stop just to keep the tires from hitting the fenders that even on-road driving will suffer.
I'm with you. Would I do personally do it, no. All I'm saying is we don't know what his goals are.

As far as travel goes I guess that depends how he feels about cutting into the tub.
 

Chris

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I'm with you. Would I do personally do it, no. All I'm saying is we don't know what his goals are.

As far as travel goes I guess that depends how he feels about cutting into the tub.
So I can't tell him to get a full Savvy / Currie setup just yet? :ROFLMAO:

You're right, we don't know what his goals are. The thread title though, it's almost like clickbait ;)

37s with a 4" lift is actually reasonable, but the amount of supporting work you need to pull it off (and make it work well) turns out to be one hell of an expensive and time consuming project.
 
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L0jik

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The ideal axle setup is a front Dana 44 and Rear Dana 60 from an old F150 or 1500 truck. These will be wider, thicker, and have larger ring gears. If you have a Dana 30/Dana 35 combo you need to just replace both because they will never handle 37s. You could spring for some JK Rubicon axles or pre-built axles like Currie/Rockjock/ECGS. If you really want to test your luck you could fully build a TJ Dana 44 rear and get a front Dana 44 from a truck and narrow it. The TJ Dana 44 still uses Dana 30 outer components and weak balljoints and is way too weak to hold up to 37s.
You'll need a big brake kit ($1200+), hydro assist ($1000+), you'll probably want beadlocks, etc, etc, etc.
IMO, 37s are really only needed for mudding as you will get better flex and stability on 35s if you are rock crawling.
 

KingCarGuyZ

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L0jik

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On a 4 inch lift with no wheelbase stretch, you'll have better stability on hill climbs and more uptravel with 35's, which makes it better for rock crawling.
When you're in mud, uptravel means almost nothing, the biggest determiner is clearance at the diff/axle tube, which would make 37's worth considering.

Am I wrong?