Another TJ on 37s thread

custommuffler

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Hello, new member here very longtime lurker. After all of my research and ordering parts I`m down to my lift and just cant decide. First off I live in New Orleans and my 15 year old is getting the TJ (99 Sahara AX15). There are no rocks and occasional mud MAYBE. This will be a mall crawler period! Ive never even taken this Jeep offroad. I want to say I have 128k on the clock could be less. Really havent driven this thing in the last 12-13 years except to sometimes get a 12 pk up the street. I had a new 97 that I orderred and ran it into the ground the first year of ownership seeing what they could do. Traded it for a showroom 99 and saw no need to destroy it since I knew its capabilities.
Ive got a 30/44, always ran a centorforce dual friction from after the first week of ownership. Why? Thats the only clutch I install at my shop or now the dual disc if available. Few mods to the motor and am either going SC or turbo really soon. Why forced induction? Cause things run better with boost, period. Ive already given my son the GTO with a maggie that laid down 752 to the rears.
So the criteria is: rims are Motiv Magnus 20x12 with `44 offset wrapped in Patagonia 37`s. 4.88`s with the stock internals. Metalcloak high fender deals (4" front is arched with matching rear and rock slider), Warn 87700 front bumper, Poison Spyder psd-14-61-030 rear. Al the LED stuff with round taillights. Jeep is still in paint. I am down to the Currie/Savvy 4" or the MC 4.5" full kit lift. Daily driven ALL street driven vehicle. I buy in thoughts of never rebuying. If I need to change axles eventually I will go bigger. Just not right now. Ive also got a plethora of bills every month and the money tree my son and ex wife have picked so clean there is no bark left. Thanks for the acceptance to the forum and any thoughts are very appreciated
 
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I'd probably go with the Currie/Savvy 4" over the MC. If you want to run 37's then you need to plant another money tree but put it somewhere hidden.

Id imagine that Dana 30 is going to struggle, even as a street vehicle. You may want to swap it out to a 44.

Welcome to the forum. Theres a lot here to research in order to run a lift and tires that big.
 
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Thanks for your reply. If I get my hand on a Rubi 44 I will but for now it is what it is. Im now seeing EVO lifts. I really am looking for a decent road ride with no wandering. Every lifted jeep that comes to the shop seems to wander. I get it alignment is properly not done right. Just scares me to death. And after owning F350`s, death wobble is not my thing either.
I like the Currie, my only question is will the ride feel a bit more harsh with JJ as opposed to the MC bushing design. I dont want to feel every pebble. There are so many lift kits, so many option that research really gets you more confused than anything. Sometimes too many options are bad.
 
Also, I see so much mention of ditching the trac bar. Please tell me more on this and what kit does just that or do I need a combo of kits. Thanks man
 
Not to rain on your parade, but this plan will result in a very very poor street jeep. Even for just the street, there is more you need to run than you listed. It will not perform well on the street without many many more modifications.

I’d get 33’s. My 35’s are not set up optimally and I dislike how my Jeep acts on the street. Can imagine how that would be with 37’s.
 
With the AX-15 and 37s, you’re going to want 5.13s (possibly even 5.38 if you get a front Dana 44). 4.88 won’t be deep enough.

A front TJ Dana 44 won’t have much additional strength in the areas needed to reinforce for very large tires. Used only for mild street use, I suspect the Dana 30 would be okay. Off-road might be a different story. Plan on replacing ball joints and wheel bearings frequently.

You will want chromoly shafts front and rear, as the 37s will significantly stress the axle shafts. You might consider a Super 30 and a Super 44 kit if you add lockers.

You’re going to want at least 5” of lift to run 37s unless you’re willing to do a lot of trimming. 4” suspension lift and 1.25” body lift is very commonly done for 35s, and could work for 37s if significant uptravel isn’t a necessity.

With 37s, you will need a big brake kit. Reach out to @mrblaine for details. I suspect he would recommend a 17” BBK or a Super 16 kit, but he would know better than me. I run a Super 16 kit on 35s and am very satisfied with the performance.
 
I run 32`s on the stock rims and I want to say 1.5" spacers. No issues at all. Literally nothing else but 411s. Only time I rub is the rears with people in the back on a good bump. Front is fine turning lock to lock.
 
Only items not purchased yet is the lift. Going back isn`t an option.

No matter what lift you buy this will go poorly unfortunately (for now). Here is what comes to my head so you can improve the Jeep over time.

-Gears are not deep enough.
-You will not have enough suspension uptravel. The metalcloak fenders do nothing for that. Real high lines, a 1.25 inch body lift, and moving the shock mounts will fix that.
-The Dana 30 will work alright for street use, but beware of the ball joints.

Fixes for the just the three things above are going to very expensive and the suspension is not unskilled work. The Jeep you have setup will get you down the road, but it will not be enjoyable. I would very much see if returning some of the items you bought is possible.

Not trying to be a jerk, but you need to throw a lot of time and money at the Jeep to get 37’s to work well. It isn’t easy.
 
No matter what lift you buy this will go poorly unfortunately (for now). Here is what comes to my head so you can improve the Jeep over time.

-Gears are not deep enough.
-You will not have enough suspension uptravel. The metalcloak fenders do nothing for that. Real high lines, a 1.25 inch body lift, and moving the shock mounts will fix that.
-The Dana 30 will work alright for street use, but beware of the ball joints.

Fixes for the just the three things above are going to very expensive and the suspension is not unskilled work. The Jeep you have setup will get you down the road, but it will not be enjoyable. I would very much see if returning some of the items you bought is possible.

Not trying to be a jerk, but you need to throw a lot of time and money at the Jeep to get 37’s to work well. It isn’t easy.

I can’t stress this enough.

This is a terrible idea, and while I don’t want to come across as a dick, 37s have no place whatsoever on a TJ unless it’s stretched, has some full width Dana 60 axles (or similar), and a lot of time and money.

Having said that, between those two choices for lifts, the Currie / Savvy lift would be my first and only choice.
 
You'll need gears front and rear and a Super 30 for your Dana 30. You'll also want a Currie Currectlync steering to help with the wondering. Theres other stuff you'll need as well....brakes like someone else suggested. Theres other stuff but I cant think of it all at the moment.

Going over 33's on a TJ gets expensive very fast.

*edit* everyone else has added similar items....I was late hitting submit lol
 
Do you know the offset or backspacing of the wheels you will be using? That will determine how far they stick out and potentially rub. Most users here use 15x8 or 17x8 wheels for 35s and 37s, and use 3.75” of backspacing. With 20x12 rims, you need anything less than 6” (ideally 5.75 or less) of backspacing to run without spacers and limit rubbing.

Extremely low backspacing or large spacers (or a combination) that make the wheels stick very far out from stock is also not a good idea. The farther out the wheels get from the axle, the more stress they put on bearings and ball joints.
 
With the AX-15 and 37s, you’re going to want 5.13s (possibly even 5.38 if you get a front Dana 44). 4.88 won’t be deep enough.

A TJ Dana 44 won’t have much additional strength in the areas needed to reinforce for very large tires. Used only for mild street use, I suspect the Dana 30 would be okay. Off-road might be a different story. Plan on replacing ball joints and wheel bearings frequently.

You will want chromoly shafts front and rear, as the 37s will significantly stress the axle shafts. You might consider a Super 30 and a Super 44 kit if you add lockers.

You’re going to want at least 5” of lift to run 37s unless you’re willing to do a lot of trimming. 4” suspension lift and 1.25” body lift is very commonly done for 35s, and could work for 37s if significant uptravel isn’t a necessity.

With 37s, you will need a big brake kit. Reach out to @mrblaine for details. I suspect he would recommend a 17” BBK or a Super 16 kit, but he would know better than me. I run a Super 16 kit on 35s and am very satisfied with the performance.

I am concerned with ball joints. Wheel bearings not at all. The tire and rim combo I chose due to light weight. No matter what this combo has to work. Im in too deep to get out now. Understood about gearing but limited with the Dana 30 to 4.88. At this stage Im really wanting long term long lasting lift kit. Tom Wood doubles will be coming after lift. I am not opposed to huge brakes as ever since the rear disc setup i did waaaay back in the day (G2 or something like that) doesnt stop as good as the drums did. I like the fact the emergency works without adjustment though. This will be a street pounder period. I havent towed anything with it in years othe rthan jetskis about a mile away.
 
Do you know the offset or backspacing of the wheels you will be using? That will determine how far they stick out and potentially rub. Most users here use 15x8 or 17x8 wheels for 35s and 37s, and use 3.75” of backspacing. With 20x12 rims, you need anything less than 6” (ideally 5.75 or less) of backspacing to run without spacers and limit rubbing.

Extremely low backspacing or large spacers (or a combination) that make the wheels stick very far out from stock is also not a good idea. The farther out the wheels get from the axle, the more stress they put on bearings and ball joints.
offset is negative 44
 
No matter what lift you buy this will go poorly unfortunately (for now). Here is what comes to my head so you can improve the Jeep over time.

-Gears are not deep enough.
-You will not have enough suspension uptravel. The metalcloak fenders do nothing for that. Real high lines, a 1.25 inch body lift, and moving the shock mounts will fix that.
-The Dana 30 will work alright for street use, but beware of the ball joints.

Fixes for the just the three things above are going to very expensive and the suspension is not unskilled work. The Jeep you have setup will get you down the road, but it will not be enjoyable. I would very much see if returning some of the items you bought is possible.

Not trying to be a jerk, but you need to throw a lot of time and money at the Jeep to get 37’s to work well. It isn’t easy.
The weld in suspension Im not concerned with at all. We`ve back halfed a couple here at the shop. My concern with JJ`s is road vibration transfering to frame. I ran solid steel control arm bushing in my 82 Cutlass back halfed. It was a trac car so ride quality wasnt a concern. But I can remeber feeling everything through the front end.
 
offset is negative 44
For Jeep and truck wheels use the backspacing dimension which is more useful to know since it provides the wheel's clearance/distance from the suspension. Offset is a different measurement that is more useful for cars.

You won't notice any additional vibration using the commonly recommended Johnny Joints.
 
I am concerned with ball joints. Wheel bearings not at all. The tire and rim combo I chose due to light weight. No matter what this combo has to work. Im in too deep to get out now. Understood about gearing but limited with the Dana 30 to 4.88. At this stage Im really wanting long term long lasting lift kit. Tom Wood doubles will be coming after lift. I am not opposed to huge brakes as ever since the rear disc setup i did waaaay back in the day (G2 or something like that) doesnt stop as good as the drums did. I like the fact the emergency works without adjustment though. This will be a street pounder period. I havent towed anything with it in years othe rthan jetskis about a mile away.
The Dana 30 can (and should) be geared to 5.13. You might be thinking of 5.38 (or even 5.89) gears, which are only available to the Dana 44.

https://www.amazon.com/dp/B01ETJQX4Y/?tag=wranglerorg-20
 
For Jeep and truck wheels use the backspacing dimension which is more useful to know since it provides the wheel's clearance/distance from the suspension. Offset is a different measurement that is more useful for cars.

You won't notice any additional vibration using the commonly recommended Johnny Joints.
Ive carefully read all your posts about the 12 years your JJ`s have worked. Hopefully longer now. Your posts are what pushed me in the Currie direction. Thank you, your opinion is valuable to my decision. Thank you
 
offset is negative 44
That might be a bit wide for the stance. You certainly wouldn’t want wheel spacers with those wheels.

That translates to 4.25” backspacing, which for a 20x12 will put the tire centerline roughly 1.75” outboard of the WMS. Most TJ owners stick to wheels that put the tire centerline within 0.5” of the WMS.

It might work, but it could stress your ball joints and bearings. It may also play havoc with the steering due to the scrub radius.

Personally, I would look for something with offset between -7mm and -22mm to reduce wear on the ball joints and bearings, but ultimately it may be a matter of personal preference. Higher negative offset numbers will reduce the odds of running at the cost of wear and tear.

It will also depend on the width of tire you end up running.