rubicon d44???

[jared]

i was just looking at "off road" magazine in borders and they did a rubicon front d44 axle swap onto an mj, they said it was a complete bolt in affair. they bought the whole axle brand new (with no guts or axle shafts etc) for just under 600 bucks at the dealership.

 

now after everything is said and done you have probably over 2000 into the axle but its all brand new and bolt on, do you think its worth it?

 

and i know tj's use rear coils, but i suppose the same could be done for the rear with some cutting and welding the new leaf pads and shock mounts to it for your xj or mj right?

[Pete M]

It's a low pinion axle. Plus I bet they have more the 2k into the one they built. Personally, I'd look into a custom unit. It'll be even better. :D

[JOMJ87]

There was a discussion on this just the other day and everyone said its not worth it you can buy a TRUE 44 and narrow it for prob just as much or way less. They arent the best axles in the rubi just cause it SAYS dana 44 don't mean it really truelly is. Look for the thread theres alot of good info in it.

 

Cole

[jared]

so the new d44 is a little (or a lot) weaker than a pre 90 version, but it is still stronger than a d30 i assume?

 

now 4wd hardware has tj d44 axles already buit ready to bolt on with detroit or arb locker, gears of your choice, alloy usa axle shafts for about 2200 dollars, do you think this might be worth it?

 

i know if you searched you could find a real d44, but after adding lockers, strongeraxles, new gears etc. you are looking at more money than that, plus installation unless you do it yourself. and you might even need to get it shortened down, weld all the brackets etc. i know this would be the better way to go, but how much stronger is this old axle than the new one.

 

and finally could you make the new one just as strong as the old one?

[JOMJ87]

I wouldnt worry with the front and I havent also My rear 35 has done great without any breakage in 4 years or so BUT i did find a 44 out of a MJ and will be putting that in the rear. Unless your going bigger than 35s I would think about the front except better Ujoints (maybe the OX ones and Maybe if ii had money to spend chromeoly shafts other than that you should be fine. The only concern with mine is I want 5.38 gears or lower and a 30 can only handle 4.88s unless its low pinion then it can take 5.38s but I don't want LP. What tires are you planning on???

 

Cole

[jared]

i have an xj right now, even tho its the same as an mj, i plan on keeping 33'' tires on it or maybe upgrade to 35's with cutting the fenders and a tid bit more lift. i have a 8.25 rear axle stock with d30 front.

 

i know for a rear axle i would probably be bettor off finding a xj d44 because its a straight bolt in affair but after regearing, adding a locker and new shafts etc etc i would still have the same amount into it as a new axle.

 

i also have 2 9'' third members laying around would those be worth building for a rear axle?

[JohnQ]

I have an 05 Rubicon and I beat the piss out of my axels. I run 35's daily with no problems. I have thought about putting the whole drive train on my MJ but that monthly payment keeps me from gutting her. :D

[Southen Crawlin]

i also have 2 9'' third members laying around would those be worth building for a rear axle?

simple answer. yes. they are bout as strong as a 60 and have better pumpkin clearance.

 

thats what I'm lookin at to possibly run on my Mj.

[86FUBAR]

I got the rubicon d44 for my mj (bare housing) and i have the superior cromos , mile marker hub conversion for it and gona run 4.88 to mach the rear. I am however gona build a custom axeltrus to suport it from C to C and it shoul d be as strong as a stock d44.cost wise it is going to run about 1300$ but i got the housing for free and i know some people that are in the diff biz which helps a bit. all said and done it will be a verry good combo.

[CWLONGSHOT]

I got the rubicon d44 for my mj (bare housing) and i have the superior cromos , mile marker hub conversion for it and gona run 4.88 to mach the rear. I am however gona build a custom axeltrus to suport it from C to C and it shoul d be as strong as a stock d44.cost wise it is going to run about 1300$ but i got the housing for free and i know some people that are in the diff biz which helps a bit. all said and done it will be a verry good combo.

 

You will be fine, as long as your truss is well designed.

 

EVEN THEN, this RUBY D44 is a good axle for this vehicle as its a bit LIGHTER then its intended useage. The D30 is a good axle and stands up well to even fairly aggressive driving on 35" tires. You can bend the housing, but mostly you will just break the DS shaft. the D44 will help huge there!!! The trussing is addressing the one WEAK spot on this axle.

 

CW

[88MJay]

Another downside to "stock" Rubi front 44's is they run dana 30 outers. That is most peoples big complaint about that axle. Well... that and the thin tubes.

[WN1998]

Why all this talk about upgrading the front dana 30? Has anyone actually broken anything? I have a dana 30 on my TJ with 4.88 gears and a detroit truetrac with 35's and haven't had any problems.

 

Why not go with a super 30 kit for $1,000 and be done with it? The 30 spline chromo shafts should be enough to stand up to 35's no problem and you will have a ARB or OX locker to boot!

[88MJay]

This stuff has been gone over for centuries (well at least it feels like it). With alloys in a LP30 the weak link becomes the ring and pinion. I know of two people that have broke their TJ LP D30 ring and pinion. One on 35's and one on 36's. The high pinion is a much stronger ring and pinion (well at least when moving forward :brows: ) than the TJ and later XJ LP D30.

 

I like the HP D30's. I've never seen actual data to back it up but I believe that a HP30 is just as strong as a LP TJ D44. Maybe not in all areas... but as a whole. They both have the same size u-joint, the same outer shafts, the same axle tubes, same brackets, etc. The difference lies in the ring and pinion only. A HP30 R&P vs. a LP D44 R&P. How much difference can there really be?

 

Now if you are talking about a real D44... especially a HPD44... that's a different animal entirely. One I wish I had under my Jeep! ;)

 

:cheers:

[Oizarod115]

 

i know for a rear axle i would probably be bettor off finding a xj d44 because its a straight bolt in affair but after regearing, adding a locker and new shafts etc etc i would still have the same amount into it as a new axle.

 

NOT A BOLT IN... XJ leafs are mounted differently and the perches won't line up with your trucks leafs.

 

(if you were talking about putting a XJ44 in your truck that is)

[jared]

^^ well right now i have an xj :D

[Oizarod115]

gotcha, just makin sure you knew it won't go right in your MJ... SUCKS cause i have an XJ44 chillin-out in storage. :headpop:

[jared]

This stuff has been gone over for centuries (well at least it feels like it). With alloys in a LP30 the weak link becomes the ring and pinion. I know of two people that have broke their TJ LP D30 ring and pinion. One on 35's and one on 36's. The high pinion is a much stronger ring and pinion (well at least when moving forward :brows: ) than the TJ and later XJ LP D30.

 

I like the HP D30's. I've never seen actual data to back it up but I believe that a HP30 is just as strong as a LP TJ D44. Maybe not in all areas... but as a whole. They both have the same size u-joint, the same outer shafts, the same axle tubes, same brackets, etc. The difference lies in the ring and pinion only. A HP30 R&P vs. a LP D44 R&P. How much difference can there really be?

 

Now if you are talking about a real D44... especially a HPD44... that's a different animal entirely. One I wish I had under my Jeep! ;)

 

:cheers:

 

so a d30 high pinion is just as strong as a d44 low pinion? i know a high pinion would be better, but i didn't think that would be stronger.

 

now if i added an axle truss of somekind would that give a d30 or d44 a lot more strength and make it worth it?

[88MJay]

I'm not saying they are equal for a fact. But, for the money it takes to go from a stock HP30 up to a TJ LP D44 it just doesn't seem worth it in my opinion. (Not that my opinion means anything)

 

A well designed and executed truss will add strength for sure. Is it necessary? That depends on what you want to do with your Jeep. If you plan on some air time... Ya I'd definately truss it. If it will be on 35's or smaller and just get the typical trail use and daily driving... it isn't really necessary.

 

A built TJ D44 with alloys, super joints, and real hubs would be a great axle. But it will take a lot of cash to build it. If I was to spend a ton of cash on an axle I'd prefer to find a HP60 and not even waste my time on a D44. That way in the future you could upgrade shafts etc. and go to whatever size tire you want (40's etc.)

 

All I'm saying is you could build a HP D60 for around the same cash as building a D44 with alloys etc.

 

In the meantime... if you aren't breaking your D30... run it and carry spare shafts. I've ran D30's for 5 plus years on 35's and I have never even broken one shaft.

 

This topic is such a big ol' can of worms. If my opinions are in anyway entertaining for you I'm more than willing to keep posting them for you! :cheers:

[Oizarod115]

yeah, the TJ front d44s are NOT the same as an old front dana 44...

 

an old D44 compared to a TJ LPD44 is like a D60. the TJ ones arent beefy anymore.

[DirtyComanche]

This stuff has been gone over for centuries (well at least it feels like it). With alloys in a LP30 the weak link becomes the ring and pinion. I know of two people that have broke their TJ LP D30 ring and pinion. One on 35's and one on 36's. The high pinion is a much stronger ring and pinion (well at least when moving forward :brows: ) than the TJ and later XJ LP D30.

 

I like the HP D30's. I've never seen actual data to back it up but I believe that a HP30 is just as strong as a LP TJ D44. Maybe not in all areas... but as a whole. They both have the same size u-joint, the same outer shafts, the same axle tubes, same brackets, etc. The difference lies in the ring and pinion only. A HP30 R&P vs. a LP D44 R&P. How much difference can there really be?

 

Now if you are talking about a real D44... especially a HPD44... that's a different animal entirely. One I wish I had under my Jeep! ;)

 

:cheers:

 

so a d30 high pinion is just as strong as a d44 low pinion? i know a high pinion would be better, but i didn't think that would be stronger.

 

now if i added an axle truss of somekind would that give a d30 or d44 a lot more strength and make it worth it?

 

 

 

 

 

 

Uh, a LPD44 is WAY WAY WAY stronger than a HPD30. Even in a front application. A HP axle being stronger in the front is a myth, based on a poor understanding of physics.

[jared]

how can i tell if my d30 is high or low pinion (99 xj)

 

since the d30 is probably strong enough, what should the rear be an older pre 90 xj d44? or something beefier?

[88MJay]

Uh, a LPD44 is WAY WAY WAY stronger than a HPD30. Even in a front application. A HP axle being stronger in the front is a myth, based on a poor understanding of physics.

Hmm... That's cool. I'm not much for big heated discussions but here is link to some of the other 708,000 people who have written about HP's being stronger....

 

http://www.google.com/search?hl=en&q=reverse+cut+gears+stronger%3F

 

As for being able to tell the two apart HP or LP?... if the pinion enters the axle housing below the centerline of the axleshafts it's a LP. If the pinion enters the center section above the centerline of the axleshafts it's a HP. You can tell just by looking at the whole axle from the side or slightly from the rear.

 

Again... :cheers:

[DirtyComanche]

Again... :cheers:

 

 

I know it sounds weird, but, they're actually wrong. Yes, in foreward motion a HP gearset in a front axle is stronger - as the gears are meshing on the drive side. BUT - how do you break a front axle in foreward motion? Well, you can, I'm not saying it is impossible, but about 75% of the vehicles weight will be being pushed by the rear axle. Hence, if your axles are of reasonably matched strengths the rear will give long before the front. Also, typically you climb over obstaces while on the throttle in a foreward motion. Now even more weight has transfered to the rear gearset - the front is pulling somewhat but it is seeing far less force than the rear. When is the load on the front axle the greatest? Well, do you compression brake down hills for all your worth? (I do, brakes are iffy) Now the HP front axle is driving on the coast side of the gears - the weak side. And the majority of your vehicles weight has transfered to the front axle as you are probably going downhill in a forewards direction. Now, as another scenario I get into sometimes, what if you have to back up while going uphill, or while bound up? Now that front R&P is on the coast side, and again the majority of the vehicles weight is on it. If you're bound up it can be even worse...

 

 

Then you get in a situation called 'Pop goes the thirdy'.

 

 

Oh, and FWIW, the difference in strength between the coast and drive sides of the gears is about 5%. Not much. Enough to matter? Sometimes. If you're a monster mudder or something, no, never. But, for the most part it is moot.

 

 

 

However, I NEVER want to hear somebody say the HPD30 R&P is as strong as the LPD44 in a front application. Remember, the D30 R&P is the same size as a D35... And that ain't good thing!

 

 

 

(But, do not in any way mistake this for endorsing the rubi-CON D44. Also bear in mind I read very little of the thread, I just saw something that irked me)

 

:cheers:

[Oizarod115]

makes sense, never knew anything about the "physics" of how that stuff worked. now i see why the 30 isnt usualy that much of an issue. (for us smaller tire folks)

 

i didnt actually know there was a strength or anything difference from LP to HP, i always wondered why TJs have LPs especaily considering their short wheelbase, doesnt that give them TERRIBLE drive angles?

[DirtyComanche]

i always wondered why TJs have LPs especaily considering their short wheelbase, doesnt that give them TERRIBLE drive angles?

 

 

Jeep cheaped out and went back to a LP front axle for unknown reasons. Yeah, TJs have driveline angle problems. But, the front is actually better than the rear normally...

 

 

My buddy's YJ now has a front driveshaft length of 48", and a rear length of 18". I think he's going to have to run a bigelow shaft in the rear.