Looking for thoughts and advice on axle swap and re-gear

97TJNM

High Desert Redneck
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Long time lurker, first time poster. To start, since I got my 97 TJ about 2 years ago, I have found many answers to problems just by looking at old threads here. I'm really impressed by the knowledge on this forum. For that, I just want to say thanks to the community here. Now, on to my dilemma:

I have a 97 TJ, 150k miles, 4.0, AX15 manual, 231 command Trac t-case, dana 30 front, dana 35 rear, 3.07 gears, 2 in. BB lift, on BFG KM3 31x10.5x15s.

The gearing sucks. It's a pig on the highway and living in mountainous northern NM, 5th is useless. I can't get enough rpms to get cruising at highway speeds. For reference, I'm running 2250 rpms at 60 in 4th. I determined I'd like to run a better gear ratio, and from what I have researched (mostly on this forum) is that 4.10 and 31's make for a pretty good daily driver/occasional offroader.

I began looking at regearing and locally getting regeared runs about $1500 per axle. So after sitting on this a bit and researching, I figured I'd look at finding a set of stock rubicon axles instead. It would get me the gearing I want, has factory lockers, hand is the "better" (subjective, I know) dana 44's.

After looking for months, I found a set of rubicon axles from an 06 that a friend of a friend had pulled in favor of 1 ton axles. His is apparently a strictly rock crawling machine. I picked up the axles for 2500 for the set, but they have an e-locker in front, ARB air locker in the rear, chromolly axles shafts, and are geared to 4.88. Disc rear brakes are a plus too.

The draw backs of this setup for me are: 1) 4.88 seems a bit numerically high for 31's. I have less than 100 miles on a brand new set of KM3's and don't really want to go to a bigger tire or put a bigger lift on the jeep. 2) I know I most likely need new drive shafts, but don't want to have the added expense of a SYE. 3) the axles were set up for a High Steer kit, so I will have to make a few adjustments. Primarily relocating the stabilizer bracket and sway bar connect brackets back to their original positions. I'm decent at basic wrenching, but I'm not a welder, so I would have to get that done by my brother who is a good welder. That means transporting them to him and back, a 6 hour round trip (but I'd get to spend a weekend with brother, so not a big deal, all in all).

So, having dropped $2500 on these axles already, and knowing that I don't really want to spend more than another $1500, I have been asking myself: have I bit off more than I can chew?

Should I sell the axles and use the $ to fund a regear to 4.10 for my current dana 30/35, or should I figure out the install of said axles and gain all the benefits of 44's with better gearing and lockers, knowing that I will be dropping several grand on making the jeep set up enough to use the capability of the new axles? Is there a way to swap in the axles without having to spend a ton on a lift/tires/sye, etc?

I feel like I've fallen down a money rabbit hole trying to get slightly better gearing for a daily driver/occasional offroader, and don't know which route to go. Any advice, thoughts, ideas would be greatly appreciated!
 
My suggestion is to sell the D44s and invest in your current Dana 30/Dana 35 setup. Unless you're needs are going to be changing in the future, it doesn't sound like you need lockers or DEEP gearing?

It doesn't make sense to modify your rig to fit the axles...

Honestly, $1500 per axle seems really steep for new gears. Does that price include a locker?
 
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My suggestion is to sell the D44s and invest in your current Dana 30/Dana 35 setup. Unless you're needs are going to be changing in the future, it doesn't sound like you need lockers or DEEP gearing?

It doesn't make sense to modify your rig to fit the axles...
Hey, thanks for the quick response! That's solid advice, and I appreciate the input. Its what the gearing guy at the local "jeep shop" suggested too. I hate leaving the capability of the setup 44's I bought, but like you said, it doesn't make a ton of sense to modify my jeep just because I got a good deal on a set of axles.
 
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Hey, thanks for the quick response! That's solid advice, and I appreciate the input. Its what the gearing guy at the local "jeep shop" suggested too. I hate leaving the capability of the setup 44's I bought, but like you said, it doesn't make a ton of sense to modify my jeep just because I got a good deal on a set of axles.
And no, that doesn't include lockers. It does seem steep, but that's the mid point of price from the 3 shops I checked. 1 said 2500/axle one said 1500/axle and 1 said 1200/axle (but is 2 hours away). All 3 shops specialize in jeeps, so I figure that must be the going rate locally. Although the 2500/axle shop seemed like they weren't really interested in the job...
 
Looks like 4.88 in 5th gear at 65mph would put you around 2700 rpm right? That's right in the sweet spot for the 4.0, but I don't have much experience with the AX15, so might wait for others to chime in. Don't be afraid of RPM's though, I've been running 3200rpm at 65mph for years with my setup, and it doesn't hurt anything.

Seems like you got a pretty sweet deal on those axles if there's not too much work to get the steering back stock or functional. It'd cost a lot more to get that same setup in your current axles with new parts
 
You don't need Dana 44's if sticking with 31" tires. Those axles just aren't setup for what you want anyway. Your axles can handle that as is.

Agree that the regear sounds expensive. Around $1500 here for both, but does depend on your area. Maybe add a locker in the rear if you think it will be used.
 
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Looks like 4.88 in 5th gear at 65mph would put you around 2700 rpm right? That's right in the sweet spot for the 4.0, but I don't have much experience with the AX15, so might wait for others to chime in. Don't be afraid of RPM's though, I've been running 3200rpm at 65mph for years with my setup, and it doesn't hurt anything.

Seems like you got a pretty sweet deal on those axles if there's not too much work to get the steering back stock or functional. It'd cost a lot more to get that same setup in your current axles with new parts
Yeah, 2700ish seems about right. I was wondering if that would be too much, but hearing you run yours at 3200 makes me feel better. Honestly, I'd prefer to use the new axles, because they are a pretty great setup. I just worry about the additional cost of getting them properly set up to run in a much more stock tj than they came out of.

Thanks much for the reply! Great food for thought!
 
You don't need Dana 44's if sticking with 31" tires. Those axles just aren't setup for what you want anyway. Your axles can handle that as is.

Agree that the regear sounds expensive. Around $1500 here for both, but does depend on your area. Maybe add a locker in the rear if you think it will be used.
Thanks for the reply! Yeah, I feel MUCH better about regearing my current axles if I could get both done for less than 2k. Maybe looking around more at regear prices is what I need to do.
 
If it were me I'd shop around for a 44 and 30 with 3.73s. They'll be bolt in ready, your tires will only be 1" over what those axles came with so your gearing won't be terrible, and you'll have a 44 for if you decide to go bigger later. I'd bet someone would throw a set in along with some cash in a trade for your rubi axles.

Supply chain issues have wrecked parts pricing, at least with certain brands. I regeared one axle in September and another in january at the same shop and during that time the price went from $1100 to $1500 per axle. Right now is a terrible time to pay for a regear.
 
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Yeah, 2700ish seems about right. I was wondering if that would be too much, but hearing you run yours at 3200 makes me feel better. Honestly, I'd prefer to use the new axles, because they are a pretty great setup. I just worry about the additional cost of getting them properly set up to run in a much more stock tj than they came out of.

Thanks much for the reply! Great food for thought!
If it's just the steering that's not stock that may not be a big deal, but if all of the stock control arm mounts are gone that'd be more of a pain in the ass.

Got any pictures of the current knuckles and steering the Rubicon axle is setup with?
 
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If it's just the steering that's not stock that may not be a big deal, but if all of the stock control arm mounts are gone that'd be more of a pain in the ass.

Got any pictures of the current knuckles and steering the Rubicon axle is setup with?
The control arm brackets look to be in the stock location. I honestly don't think returning them to usable for me would be too hard for a welder of my Brother's skill. I can get some pics posted later today.
 
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If it were me I'd shop around for a 44 and 30 with 3.73s. They'll be bolt in ready, your tires will only be 1" over what those axles came with so your gearing won't be terrible, and you'll have a 44 for if you decide to go bigger later. I'd bet someone would throw a set in along with some cash in a trade for your rubi axles.

Supply chain issues have wrecked parts pricing, at least with certain brands. I regeared one axle in September and another in january at the same shop and during that time the price went from $1100 to $1500 per axle. Right now is a terrible time to pay for a regear.
That's a great idea, actually. Of course, I'm still pondering what way I'm going to go, but I can always post em up in the buy/sell/trade section in a few days if this option makes the most sense! Thanks!
 
Your initial post described your needs as "daily driver/occasional offroader." It just seems like spending additional funds to make the D44s work under your rig will end up giving you some really nice equipment that you don't really need and may not even use?

On the other side of that coin is perhaps a gateway to expand your capabilities and take your wheeling to the next level. Those Dana 44 are built for alot more than "occasional offroading." Only you can answer that question though.

Have you considered sourcing Dana 30/ Dana 35 axles from a 4-cylinder TJ? Those Jeeps came with 4.11 gears and are usually not too hard to find. They would bolt right into your current setup, no welding or modifications needed, and would perform much better with the 31" tires than what your rocking now. I'd wager you could find the pair for much less than $3k, the price you're considering for the regear.

Just a little more food for thought.
 
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Your initial post described your needs as "daily driver/occasional offroader." It just seems like spending additional funds to make the D44s work under your rig will end up giving you some really nice equipment that you don't really need and may not even use?

On the other side of that coin is perhaps a gateway to expand your capabilities and take your wheeling to the next level. Those Dana 44 are built for alot more than "occasional offroading." Only you can answer that question though.

Have you considered sourcing Dana 30/ Dana 35 axles from a 4-cylinder TJ? Those Jeeps came with 4.11 gears and are usually not too hard to find. They would bolt right into your current setup, no welding or modifications needed, and would perform much better with the 31" tires than what your rocking now. I'd wager you could find the pair for much less than $3k, the price you're considering for the regear.

Just a little more food for thought.
And I think you've hit the nail on the head. I suppose I'm at a crossroads now. Do I make it more suitable for my current needs (that frankly I never saw the need to expand into more serious offroading) or do I use the axles I bought and make it much more capable offroad, knowing that I didn't intend to do so (but admittedly think it would be pretty sweet) knowing I'm going to have to invest more $...

It sucks, but that's my delimma. The siren call of Lockers...🤣
 
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If it were me I'd shop around for a 44 and 30 with 3.73s. They'll be bolt in ready, your tires will only be 1" over what those axles came with so your gearing won't be terrible, and you'll have a 44 for if you decide to go bigger later. I'd bet someone would throw a set in along with some cash in a trade for your rubi axles.

Supply chain issues have wrecked parts pricing, at least with certain brands. I regeared one axle in September and another in january at the same shop and during that time the price went from $1100 to $1500 per axle. Right now is a terrible time to pay for a regear.

If you decide to consider this option I know guy who would be glad to discuss that swap with you. LJ axles so rear disc and limited slip.
 
If you decide to consider this option I know guy who would be glad to discuss that swap with you. LJ axles so rear disc and limited slip.
Thanks much. I'm going to let this post continue to play out and keep considering my options and listening to opinions for the next few days. If I decide to go this route I'll let you know though!
 
If it's just the steering that's not stock that may not be a big deal, but if all of the stock control arm mounts are gone that'd be more of a pain in the ass.

Got any pictures of the current knuckles and steering the Rubicon axle is setup with?
Here is a pic of each axle. Not great pics as they are currently under my camping trailer under the carport, but hopefully good enough to get an idea.
20211024_151443.jpg
20211024_151428.jpg
 
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