subcribed for info. I'm Looking at axle swaps for when I return from deployment as well. haha.

 

I got 8 more months of planning for this deployment. I'm curious as well about the JK axle swaps. I need to get rid of the D30 i still have up front lol.

 

Bump! No one has any install tips, tricks, or pics of JK axle install on a TJ/LJ??

 

I wanted to start a thread to collect any or all info, tips, and install pics on swapping JK axles into a TJ or LJ. Mainly because I want to do it to my jeep when I get back from Afghanistan ( if my wife lets me :rtft: ) and maybe someone else out there is looking for information as well. I know there are a few people on here that have done it (Bennettj13, Hendrix, MrBlaine,B2carpen,Lo1aY) , but it's not exactly easy to find info and/or pictures of the install process.

I have read online that some people have done front and rear JK axle swaps for $2000 - $3000.

Please correct me if I'm wrong, but this is all I know right now about JK axles compared to TJ axles.
- The JK axle is wider appx 5in wider
- An Unlimited JK weighs over 1000lbs more than a standard TJ, so a TJ may or may not need that much reinforcing compared to a fully loaded JK.
- JK D44 has a much stronger ring and pinion compared to a TJ D44
- The front JK D44 axle has higher pinion VS the standard LP TJ axles.
- Steering components and knuckles are beefier and stronger.
- The stock JK Rubicon axles are 32 spline, the JK non-rubi axles are 30 spline vs the 30 spline TJ Rubi axles. Or even the 27 spline D35 and D30 TJ axles.
- Larger brake components (rotors, calipers, pads) available at any parts store. Added disc brake upgrade with OEM parts if going from TJ35 to JK44

To start off, what would be better?
- An axle truss like the ones from TnT Customs, or just an axle bracket kit from Rubicon Express or Other Company?
-Is an axle truss overkill and not necessary, or definitely worth the money?
-Should you sleeve the axles? Inner or outer sleeves? Both?...

Thanks in advance for any information. :cheers2:

All JK outers are 32 spline.

Axle truss is never over kill but usually if you are upgrading to axles like these you plan on bigger tires and harder wheeling so yes I'd run an axle truss.

Wouldn't need to sleeve and axle but it all depends on tires size and how you drive.

 

Also with them being wider. It's cheaper to start out with a ford HP 44 (which is 3/4 ton and considered better then these 44's but a lot will debate this) and upgrade all components on this. I'm assuming with a JK 44 you'll just remove all brackets, throw on a trust (I would if you wheel hard) put on new brackets, new steering and roll with the factory gearing and lockers.

 

Electric lockers in 06 LJ

Subscribed for info.

Been thinking of this swap myself... to run JK wheels with 35x12.50 tires without spacers.

Also to add.... how to make the electric lockers work with TJ/LJ Rubicon factory switch ?

 

Thanks for the replies! Now we are getting somewhere.
To start off, I considered doing the JK axle swap just for 2 reasons.

-You can get these axles online and at salvage yards for a decent price.
-As for maintenance, you can easliy get parts at a local parts store and at a lower price that 1ton axle parts.

I’m not a rock crawling guy, so I’m going for more of the expedition style vehicle, and maybe tow a small tent or teardrop trailer, 34’’- 35’’ max tire size and I already have JK wheels. I see on Lo1aY’s LJ build he used TnT custom trusses. That seemed like a nice option compared to a whole axle bracket kit. I just didn’t know if trusses were unnecessary considering a TJ is about 1000lbs less than a JK Unlimited. Also I would not have to run wheel spacers to prevent tires rubbing on the rear springs.

 

Some parts are stronger than TJ axles but your still going to have the same weak hubs and ball joints. If your gonna spend all that money and dont mind the wide WMS your better off doing a HP44/60. Also look into waggy swaps. May be a little harder to find. Took me forever to find my waggy 44 but I live in the rust belt. Out where u are should be a lot easier. With a HP44 or 60 you will also have the option of manual hubs which are a real nice feature for strength and relieving some stress on your drive line when ure not on the trail.

 

That's good to know, I was unaware that JK's have poor ball joints. I would have guessed the JK used better joints. I know some people have had poor luck with their TJ's and part store replacement ball joints.

You have a waggy 44 in the front, what's the width WMS-WMS of that axle?

 

On a added note, you can get a set of TnT Customs axles trussed (same setup as Lo1aY used on his LJ build) for under $1000 without shipping. So if I can get a decent priced set of used JK axles, I can do this for around $3000 doing the labor and welding myself. About the same price as a G2 rear D44 with disc brakes + shipping.

At one time I was considering front and rear G2 axles for my jeep. I would need front axle, rear axle, TJ bolt pattern wheels, and other misc. parts. That would be easily over $6000.

 

I would do a Ford hp44 long before a JK 44. They are similar strength-wise but the ford axle is much cheaper. You can even find them already built for a decent price if you are patient. I bought my Ford HP44 for $900, and it had 5.13 gears, ARB air locker, chromolly shafts, and high steer. They are 65" wms to wms, but with proper backspacing on your rims you can be back to near TJ width.

 

The main advantage of the jk 44 is that it's a new gen 44 and has a ring gear and pinion that are only a c-hair smaller than a d60's. Get a wider stance, 60 strength if built right and good ground clearance....yea I'm in. But I'm going one step further. I'm gonna put Ried 60 inner and outer c's on it so I get the 1ton outer strength and no ball joints. It's not going to be cheap but its what I want and I should be ale to get the housing cheap.

 

You are aware that it is only the rear JK 44 that has the 8.9" ring gear right? The front JK 44 has the same 8.5" ring gear as any other 44.

 

The main advantage of the jk 44 is that it's a new gen 44 and has a ring gear and pinion that are only a c-hair "BIGGER"than a "d30's"

Fixed it for ya :cheers:

They are not even close to having the same size inner c's as a 60

 

Fixed it for ya :cheers:

That's not true either.

D30 ring gear - 7.2"
D44 ring gear - 8.5"
D60 ring gear - 9.75"

A d44 is basically halfway between the strength of a d30 and d60.

 

The ford hp 44 has the same small u joint the stock Dana 30 has where the jk 44 uses a larger u joint. The outer c's are weaker on the jk than the tj and should be gusseted.

The ball joint in either 44 are about the same strength wise, so every little to debate there.

Unit bearings are more than fine and are much easier to change if need be. I don't see a real advantage to the old bearing and race setup.

Don't ever use re brackets since they use hour glass bushings on the front uppers.

While late 70's ford f250 hp Dana 44 had .500 walled axle tubes they were 69.5" wide wms to wms and still use the same small ball joint and u joint.

Having had a wagoneer Dana 44 in my jeep and swapping it out in favor of a hp30 I can say there is little to no advantage of having the lp 44 other than a wider selection of gear ratios. While the waggy and ford 44 do have a larger pinion shank and ring gear it's a bit moot since these axles break at the same spot the Dana 30 does 99.9% of the time. That would be the u joint and again they all use the same 5-760x joint.

The Dana 44 also costs you ground clearance and diff to track bar clearance as well.

My advice would be buy an explorer 8.8 rear and a hp30 front. Throw some factory 10 shafts in, an Aussie locker up front and a arb, or Detroit in the rear.

 

The ford hp 44 has the same small u joint the stock Dana 30 has where the jk 44 uses a larger u joint. The outer c's are weaker on the jk than the tj and should be gusseted.

The ball joint in either 44 are about the same strength wise, so every little to debate there.

Unit bearings are more than fine and are much easier to change if need be. I don't see a real advantage to the old bearing and race setup.

Don't ever use re brackets since they use hour glass bushings on the front uppers.

While late 70's ford f250 hp Dana 44 had .500 walled axle tubes they were 69.5" wide wms to wms and still use the same small ball joint and u joint.

Having had a wagoneer Dana 44 in my jeep and swapping it out in favor of a hp30 I can say there is little to no advantage of having the lp 44 other than a wider selection of gear ratios. While the waggy and ford 44 do have a larger pinion shank and ring gear it's a bit moot since these axles break at the same spot the Dana 30 does 99.9% of the time. That would be the u joint and again they all use the same 5-760x joint.

The Dana 44 also costs you ground clearance and diff to track bar clearance as well.

My advice would be buy an explorer 8.8 rear and a hp30 front. Throw some factory 10 shafts in, an Aussie locker up front and a arb, or Detroit in the rear.

Most of that is true, with a couple exceptions.

It is true that a ford hp44 uses the same u joint as a d30, however, the lockout hubs allow you to run 300m u joints like CTMs, where you will break a shaft long before a u joint.

F150 HP44s are 65" wms to wms, and F250 HP44s are 67" wms to wms. Not sure where you got 69.5" from but that is wrong.

 

The Jk unit bearings supposedly don't come apart if you break a stub like a tj one will

You NEED to truss or at the very least do c gussets on a Jk front 44. They bend. It's a way of life for Jk folks. Poly and Evo both make nice kits for trussing and inner c gussets.

Balljoints are what they are. They don't last long in lifts Jk's. but Jk's do weigh a lot more (as a general rule. It's not uncommon to see 6000 lb unlimiteds). Dynatrac makes pretty much indestructible balljoints for them. And poly makes a nice upgrade for the balljoints.

Jk lockers are 12v and very easy to wire. However during the regear its easy to break. I also usually cut off the plunger for the locker engaged light too.

They use carrier shims that don't go under the bearings. So setting them up is generally easier than those which require shims under the carrier bearings.

Jk's have flanges on the pinion so you'll have to source yokes for the pinions.

 

I was looking at spending 6k on some g2's, but since my goal is 35" expedition/dd jeep I think these will suit me well.
Since I live so close to daveys jeeps, I might be on the waiting list.

 

That's not true either.

D30 ring gear - 7.2"
D44 ring gear - 8.5"
D60 ring gear - 9.75"

A d44 is basically halfway between the strength of a d30 and d60.

Oops... Haha

I thought I it said the inner c was only a hair smaller than a 60. Which is not true. It's barely bigger and weaker than Tj inner c's.

I just re read it and I mis read it the first time around

The gears are still basically in between a 30 and 60

But the pinion is nearly identical to a 60

Thus is why the new gen44 is somewhat stronger than the older fords

But how many times do you hear of people popping there ford 44 pinions. I never have. Jk gears are just extra security IMO

 

I think your best axle choice really comes down to what tires you want to run.

The JK44 would be an awesome axle if they had a stronger C/ball joint, and didn't cost so much. You can gusset the Cs, replace the ball joints with poly or dynatrac when they stock ones fail, and be pretty well off.

Coming from a TJ d30, the swap to a d30 from a JK might be the best option for 35-37 inch tires max. Still gusset the Cs, do the balljoints etc. and sleeve and truss as you see fit. The gears are the reverse cut so they are already much stronger than the TJs, but if you want some extra insurance and are putting in new gears, get them cryo treated first. The big selling point is the U joints, which is what you break most of the time anyways. As long as you are staying away from gears lke 4.88s where the teeth get so small they are easy to break, the gears should hold up fine. Obviously the D44 ring/pinion would be preferable, but for the extra money, probably close a grand, to pick one up, I'd rather sling that money into beefing up the 30. Now if you are going to be wanting deeper gears, 37s-40s, etc, I would go the d44 route or even at that point to a d60. Personally the JK axles are the only thing short of a 60 I have considered for my rig personally, because of the U joints. I don't see the point sinking more cash into the shafts and CTM U joints, or doing RCVs, when that itself will cost more than the rest of the axle.

 

I think your best axle choice really comes down to what tires you want to run.

The JK44 would be an awesome axle if they had a stronger C/ball joint, and didn't cost so much. You can gusset the Cs, replace the ball joints with poly or dynatrac when they stock ones fail, and be pretty well off.

Coming from a TJ d30, the swap to a d30 from a JK might be the best option for 35-37 inch tires max. Still gusset the Cs, do the balljoints etc. and sleeve and truss as you see fit. The gears are the reverse cut so they are already much stronger than the TJs, but if you want some extra insurance and are putting in new gears, get them cryo treated first. The big selling point is the U joints, which is what you break most of the time anyways. As long as you are staying away from gears lke 4.88s where the teeth get so small they are easy to break, the gears should hold up fine. Obviously the D44 ring/pinion would be preferable, but for the extra money, probably close a grand, to pick one up, I'd rather sling that money into beefing up the 30. Now if you are going to be wanting deeper gears, 37s-40s, etc, I would go the d44 route or even at that point to a d60. Personally the JK axles are the only thing short of a 60 I have considered for my rig personally, because of the U joints. I don't see the point sinking more cash into the shafts and CTM U joints, or doing RCVs, when that itself will cost more than the rest of the axle.

I paid 1600? I think for a front Jk d44 already trussed, gussetted, with sleeves and 4.88s alloys and a spyntec kit.

I can't see a 30 being worth the effort to swap. You have all the same weak tube and inner c issues and a weaker ring and pinion.

By the time you're done building it you're going to e the same $. Considering you can probably leave the stock inners in the 44 vs alloys in the 30.

Also in the jk 30 5.13s seem to hold up just fine. It's different than a tj 30. The pinion is way bigger. And I went 5.38s in the 44s when I swapped them.

Just my .02.

 

I put JK Rubi. 44's on my ZJ i recently sold. I bought axle bracket kits from CLayton Offroad, other than the park brake cables, nothing hung below the axle tubes. Poly performance Ball Joints, and some c gussets were the only upgrades needed. Oh and i had 35" tires (315/70r17's)
I loved them as an upgrade over the 30/35 combo, they had the 4.10 gears i wanted, and I'm looking for another set for when I lift my latest TJ. They will make your rig wider, but you can use stock JK wheels to pull the tires in alittle bit. I did notice a difference in side hill stability, but i also modified my rear shock mounts when i put the axles in.
Also, you'll need adapter flanges to bolt up to the pinions, or swap out the stock flange on the axle for a 1310 yoke when you regear. Short wheel base TJ, I'd swap the flange to a standard 1310 yoke.

These are just my humble opinions/experience YMMV

 

So, just to start a list of recommended parts need for a JK to TJ/LJ axle swap are:

*JK Front Axle and JK Rear Axle.
*TnT Customs Axle Trusses F&R.
*F&R 1310 U-Bolt Pinion Yoke.
*Synergy Manufacturing C Gusset Kit.
*Dynatrac HD Ball Joints.

-Those who have done the swap, did you reuse your e-brake cables or buy a new set. Would the universal Teraflex cables work?
-What did you do for steering linkage? OEM, Aftermarket Upgrade, Custom?

 

To answer a few earlier q's

-I reused the e-brake cable, on the JK rear end you can fit the old e-brake cable with a nut and bolt.

-I re-used the JK steering linkage, just reamed out the pitman arm to fit.

- All Brakets were custom

 

Don't forget the synergy sleeve kit as well. Those housings use the same small diameter thin walled tubing the tj housings do.

 

I would do a clamshell over the outside before inner sleeves. if you do tht you can upgrade to larger shafts in the future. vs sleeves which limit you to stock sized shafts.

 

Just wondering how a sleeve kit would limit axle shaft thickness...I'm looking at the synergy kit which has an ID of 1.5" and the shafts are only like 1.3" if I remember correctly. Please elaborate if its like a sea issue or something like that.

 

35 spline shafts.

The only JK-specific inner sleeves that will work with 35 spline shafts are from Nitro. They have a smaller wall thickness and, thus, a larger ID. I actually have some on my shelf of JK parts for the future front axle build right now.

 

More splines is pretty much always going to mean a bigger root diameter. I'm sure some companies have a little variance of the rest of the shaft, but the neckdown is usually just an effort to spread out what difference there is in diameter so there is no one weak point. The splined shaft is actually supposed to be bigger than the rest of the shaft, but you don't really see that much(OEM shafts are wrong). The info I found is that the major (outside) diameter of 35 spline shafts is 1.5". The minor is around 1.41". Assuming the rest of the shaft is bigger like you typically see, not smaller, you see the issue. If the rest of the shaft actually follows proper neckdown, the shaft "body" will fit, but the problem is you still can't get the splined end through a tube that shares the exact same diameter. If you can, it would probably take a press. So like mentioned, you need a slightly thinner sleeve that has a bigger ID. But I don't know of any companys that actually follow proper neckdown, so the body of the shaft is going to be bigger than 1.5" by a little bit.

I doubt Imped knows the specific size and shape of every aftermarket shaft out there. But what I can tell you is they are at least 1.5" at the splines, and the rest of the shaft is more, but how many you'd have to look up.

 

I believe most Dana 44 35 spline shafts are 1.5". Considering all Dana 44's I've ever heard of have a 45 degree spline pressure angle and all I've ever seen have the same size splines, the diameter will be directly proportional to the number of splines.

So, my current rear 35 spline Dana 44 axle shafts should be the same diameter as any 35 spline axle shaft made specifically for JK Dana 44's. And I believe that is 1.5".

 

the only reason I say clamshell over sleeves is because you're cutting all the brackets off anyway. That said, if there's sleeves that'll work with 35 spline shafts then that's cool too.

 

If all of the brackets are going bye-bye then it only makes sense to use outer sleeves. The increase in OD will provide more strength than increasing the ID. You could do both if you're feeling really saucy.