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37s on mostly stock components

Old 05-26-2015, 05:54 PM
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Default 37s on mostly stock components

Hi all,

I'm thinking of upgrading to 37" tires on 18" rubicon wheels sometime this fall. Other than the lift kit I just installed (springs, shocks, new front track bar) am I good to do this? I've got the clearance with my fenders and wheel spacers.
Old 05-26-2015, 05:57 PM
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Wheel spacers to move the tires out. Read a few threads on gussets/sleeves/truss. And maybe a few on axle shafts/balljoints/hubs. And one on trimming the pinch seams/rails if needed. And ...
Old 05-26-2015, 06:10 PM
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Originally Posted by nthinuf
Wheel spacers to move the tires out. Read a few threads on gussets/sleeves/truss. And maybe a few on axle shafts/balljoints/hubs. And one on trimming the pinch seams/rails if needed. And ...
I'll do that. I guess I'm trying to figure out is if there are any big dollar upgrades I need to plan for in addition to the tires themselves.
Old 05-26-2015, 06:22 PM
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Just depends. Some people are fine running 37's while basically stock. Others will do the whole domino thing where it is one item after the other that breaks and has to be fixed/replaced.

Read, then re-read, as many threads as you can find on the various problems, and what the fixes are, then start setting money aside for those eventual problems, and you will be ahead of the game. Ya know, go into it with a 'when it happens', not 'if it happens' attitude.

Or just skip the whole build-up/worry about it phase and go straight to tons...

Last edited by nthinuf; 05-26-2015 at 06:25 PM.
Old 05-26-2015, 09:09 PM
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I am in the process of going to 37's. I wouldn't think about wheeling with them without gussets and at least sleeves. I just put on a truss, gussets, and am upgrading the axles. If your just mall crawling you may get away with stock equipment but I plan on wheeling fairly hard and hate trail repairs.
Old 05-26-2015, 09:28 PM
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I can't speak from personal experience but a friend that I wheel with had been running on 35s for a few years with no issue what so ever on stock rubi axles with rcv's. Just recently put 37s on and first time out he completely bent the whole housing and tie rod and also destroyed his rcv's because of it. As every one on this forum has said a hundred times over you should install C gussets and sleeves as a minimum.
Old 05-27-2015, 05:19 AM
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You are definitely going to want a gearing change and I would not mess with using the factory wheels. Find a set of aftermarket 16" or 17" wheels with a back spacing of 3.5" or less. You will save money on the rubber and if you have to purchase adapters the cost should be a wash.
Personally I never broke more stuff then when I ran 37's on rubi axles. Proper gearing is a must to take the stress off the drivetrain and its really not that hard to break axle shafts or bend the flanges.
Old 05-27-2015, 05:28 AM
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Same here. I had fully built Rubi axles and in one season on 37s my broken parts bill was over $2k, and that included blowing up the front ring and pinion. Off-road, going from 35s to 37s didn't really make a difference 95% of the time. Sucked not having hydro assist.

As noted, gusseting the C's a requirement (although, I wouldn't even run 35s without C gussets). If you wheel, you need to truss or sleeve the axle - or be willing to buy a new axle if/when yours bends.
Old 05-27-2015, 01:54 PM
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All great advice!

i went from 33's to 37' and I went kind of extreme and replaced the entire axle housing and axles, new drive shafts and added ARB lockers and regeared to 5.13

i bought real basic steel rims and put the money into tires Goodyear MTR /K's

www.roadends.info

kind of a blog on my Jeep's build to date

matthew

Last edited by Matthewd5; 05-27-2015 at 02:00 PM.
Old 05-27-2015, 03:16 PM
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So, starting with the gussets... from what I've seen online, that requires welding, which is something I'm extremely neither equipped or qualified to do. Is the fact of welding true?

Short of replacing the axles, what am I looking at (not including professional installation, wheels and tires), $1k? 2?

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