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d44 vs d30?

Shran

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Good score, those are hard to find for that price.
 


4x4junkie

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Actually if you use the axle shafts with the larger joints and TJ passenger side shaft, it's not really any weaker than a D-35 TTB.
The housing and the ring & pinion gears are all weaker.
 

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Actually if you use the axle shafts with the larger joints and TJ passenger side shaft, it's not really any weaker than a D-35 TTB.
Except for the smaller ring gear, and the fact that its live axle. (the conversion cost as much as D44)
 

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The housing and the ring & pinion gears are all weaker.
With all due respect to you Junkie, because you do have a well built truck and I know it gets wheeled, but while true, its not a signifcant difference. I see all the time people saying the D35 uses same parts as a 44, and is almost as strong.. ect, but in the next sentence talking about how much stronger it is over a D30.

D30 - 7.2" ring gear. 27spline 1.16" shafts. 297x

D35 - 7.5" ring gear, 27spline 1.16" shafts. 297x

D44 - 8.5" ring gear 30spline 1.30"/19spline 1.21" 297x

I dont know about you, but when I had a D30, I didnt have but 1 gear failure and none with the housing. I kept blowing up the small 27spline shafts.

the 27spline shaft is definitly the weakest link on both axles. In my opinion, and the facts of numbers. The D35ttb is much closer in strength to the hp30 than the D44.

and these are just stock numbers, that isnt including the aftermarket upgrades for the D44 to send it into a completely different bracket.
 
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NMB2

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this happened once with the smaller 260x joints after i locked it


Then I got the D30 shafts with the bigger 297x/760x joints in it, and this became a semi-regular occurance.


I could wheel most of the time without problems on 35" MT/R's but there was always the thought that if i get hung up in an undercut or mess around and hammerto hard, a shaft would pop. I broke a shaft at least every 2-3 trips out, and that was back when i was wheeling every weekend.
 

4x4junkie

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The D35 also has a slightly larger pinion shaft diameter than both the D30 and D44 (less gear deflection). This combined with the slightly larger ring puts the D35's gears quite a bit ahead of the D30's.

On stock shafts with stock 5-297X u-joints, the u-joint's hot-forged cross is usually the weak link.
You put cold-forged 5-760X u-joints in with full circle clips on the caps, the D44's little 1.09" necked down shaft then becomes the weak link. On the D30 & 35, it tends to be the 27 spline ends.
The R&P gears makes the most important difference though IMO. The D35 (and D44) gears are still significantly stronger than even a 760X-prepped shaft, where on the D30, this margin is far smaller. This is why fairly often (although not every time) you'll see gear failures on D30s, but almost never on the D35 or a D44 (take a look over on Pirate, there's tons of people showing off their busted up D30 gears. Yet R&P failures are not overly common even on the crappy POS rear Jeep D35, it's almost always broken shafts).
I sure would rather have break a cheaper easily replaceable part (the shaft) than something that requires a complete teardown of the axle in the shop (gears).

Of course you do have to know the limits of your truck too. If you feel you have a tire bound up, then try to reposition. Hammering it with a tire bound up against a rock can land you a broken 5-806X joint in a 35 spline D60 shaft just the same.


Edit:
I just realized that shaft has a c-clip groove on the end of it. That tells me it's not a D30 shaft. What axle is it from?
 
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NMB2

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The D35 also has a slightly larger pinion shaft diameter than both the D30 and D44 (less gear deflection). This combined with the slightly larger ring puts the D35's gears quite a bit ahead of the D30's.

On stock shafts with stock 5-297X u-joints, the u-joint's hot-forged cross is usually the weak link.
You put cold-forged 5-760X u-joints in with full circle clips on the caps, the D44's little 1.09" necked down shaft then becomes the weak link. On the D30 & 35, it tends to be the 27 spline ends.
The R&P gears makes the most important difference though IMO. The D35 (and D44) gears are still significantly stronger than even a 760X-prepped shaft, where on the D30, this margin is far smaller. This is why fairly often (although not every time) you'll see gear failures on D30s, but almost never on the D35 or a D44 (take a look over on Pirate, there's tons of people showing off their busted up D30 gears. Yet R&P failures are not overly common even on the crappy POS rear Jeep D35, it's almost always broken shafts).
I sure would rather have break a cheaper easily replaceable part (the shaft) than something that requires a complete teardown of the axle in the shop (gears).

Of course you do have to know the limits of your truck too. If you feel you have a tire bound up, then try to reposition. Hammering it with a tire bound up against a rock can land you a broken 5-806X joint in a 35 spline D60 shaft just the same.


Edit:
I just realized that shaft has a c-clip groove on the end of it. That tells me it's not a D30 shaft. What axle is it from?
passenger side D30 shafts have c-clips (before you take them out and throw them away that is).

I just searched quite a bit, on PBB and using google to find posts in jeep boards and the majority of D30 gear failures i found were LP30 gears. Not alot of HP30. The majority of failures and jeepers concerns on the HP30 was axleshafts and U-joints or the u-joint ears. Both with 260x and 297x.

Also after looking up gear specs. the D30, and D44 have a 1.38" pinion shaft and D35front has a 1.41" pinion shaft. That is not a significant increase. The D60 however has a pinion diameter of 1.625" which i would consider a significant increase.

I dont know a whole lot about the 1.09" neckdown on some of the D44's but i would assume it was done to "tune" the shaft. I would definitly upgrade shafts, like most everyone does anyways, though. I consider shaft upgrades a given when building a rig.

I agree to know the limits of your truck, which is exactly what i was speaking about in the last post with how i woul have to take it easy to avoid breaking shafts and Yes you want the weaker/cheaper parts to break instead, but I think the point is to build something that wont break.

My axle shaft assemblies are rated for around 10,000 - 12,000lbs (according to online sources and manufacturer specs), I'm not too worried about breaking one, even in the worst conditions my Dana60's breaking are the last thing on my mind.


Everything aside I will say that the D35ttb is a stout little unit, I've seen it used in person and online and it'll take some abuse... but so will a D30. I still consider them to be nearly equal axles with the D35 having the obvious slight advantage of differential size.
 
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4x4junkie

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Ah, I forgot, it's a disco shaft. That would explain the groove.

Differences like .03" on the pinion shaft and 0.36" on the ring might not seem like much on paper, but they do add up when the strength margin is as small as it is on the 30. I frequently see it out in the real world too (hard not to get caught within a sea of Jeeps on pretty much any good trail lol :icon_twisted: ). Yes LP gears are more susceptible to failure, but I've witnessed a least one HP break too (wasn't yours HP also?).

As for the D44 neckdown, it seems a little excessively deep to me (and too short in length) for tuning reasons, but I don't know for sure. I wonder if it was built in for some kindof safety reason or something, being I've only ever seen it on front steering axles (rear D44 shafts don't have them). Whatever the case, it makes them pretty equal to the D30/35 stuff, so the benefits of the even larger D44 diff/R&P vs. the D35 aren't able to be realized that well. Shafts without the neckdowns would certainly help however.
 

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Whatever the case, it makes them pretty equal to the D30/35 stuff, so the benefits of the even larger D44 diff/R&P vs. the D35 aren't able to be realized that well. Shafts without the neckdowns would certainly help however.
I agree 100%.

but as stated before, if you're going to build an axle like that, you might as well get 4340 shafts, then it puts it up into an entirely different class.


and yes my D30 gears I broke were HP. the gears broke after several shaft and joint failures and my locker that blew up and chewed them up a little bit. They lasted for about a year or so with the chewed up gears before they finally chipped and started locking/skipping.
 

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D44 all the way

Depending on where you get the D30 from (year/model vehicle) you have many advantages with the D44 over the D30. All this, of course, depends on your personal requirements/desires but here are a few things that come to mind:

- D44 has REAL wheel bearings that can be serviced and replaced a lot less expensively than the D30 unit-bearings.

- The D44 has disconnect hubs. With the D30 you would have to perform this work for an additional $$$$ cost and limited return in functionality.

- The D44 is just a larger, heavier, stouter unit that will better accommodate the eventual case of "bigger-itis" later on than the D30 will.

- Bigger components, greater options for brakes and knuckles (i.e.Hi-steer arms, kits, etc.) for the D44 are much more varied and affordable.

- I don't see that narrowing of the D44 (if necessary or desired) to get the desired WM distance as that big a challenge for the return on the investment.

This is all my own OPINION and should be taken as such. Ultimately what you plan to do with the vehicle, today and in tomorrows to come, should help you make your decision on which way to go.

Good luck and have fun no matter what you do.
 

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but as stated before, if you're going to build an axle like that, you might as well get 4340 shafts, then it puts it up into an entirely different class.
Naw, I'd just get a D60. The return for the $$$ is much better on it :icon_thumby:
 

NMB2

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Naw, I'd just get a D60. The return for the $$$ is much better on it :icon_thumby:
If you dont get aftermarket shafts with aftermarket joints, the D44 and D30 shafts are now the same. Seems rather pointless to swap in a D44 and then use the stock shafts that are the same as a D30/D35.


I love my 44 in the front of my Jeep (swapped out a built 30), but the 44 has become a money pit and has quite a bit of coin tied up in it. For what I am doing with the Jeep, a D30 would have lasted quite awhile since it was polished (Detroit, alloy shafts and joints, diff cover, aftermarket gears).


In the end it basically comes down to money and how much you are willing to spend. A D30 is small version of the D44, with the main upgrades being larger brakes and larger R&P, but is it worth the extra expense of finding the axle and having to swap wheels?
Yes, some of those costs are incurred with a D30 too, but the real benefits of a D44 are not stock and still require more money to be spent.
 

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The D35 also has a slightly larger pinion shaft diameter than both the D30 and D44 (less gear deflection). This combined with the slightly larger ring puts the D35's gears quite a bit ahead of the D30's.

On stock shafts with stock 5-297X u-joints, the u-joint's hot-forged cross is usually the weak link.
You put cold-forged 5-760X u-joints in with full circle clips on the caps, the D44's little 1.09" necked down shaft then becomes the weak link. On the D30 & 35, it tends to be the 27 spline ends.
The R&P gears makes the most important difference though IMO. The D35 (and D44) gears are still significantly stronger than even a 760X-prepped shaft, where on the D30, this margin is far smaller. This is why fairly often (although not every time) you'll see gear failures on D30s, but almost never on the D35 or a D44 (take a look over on Pirate, there's tons of people showing off their busted up D30 gears. Yet R&P failures are not overly common even on the crappy POS rear Jeep D35, it's almost always broken shafts).
I sure would rather have break a cheaper easily replaceable part (the shaft) than something that requires a complete teardown of the axle in the shop (gears).

Of course you do have to know the limits of your truck too. If you feel you have a tire bound up, then try to reposition. Hammering it with a tire bound up against a rock can land you a broken 5-806X joint in a 35 spline D60 shaft just the same.


Edit:
I just realized that shaft has a c-clip groove on the end of it. That tells me it's not a D30 shaft. What axle is it from?
First of all, the idea of a .030" in difference in pinion shaft diameter between the HP D35 and HP D30 having less deflection is simply rediculous, especially when you have a big pinion bearing that transfers the load before it even gets to that point.

Second, if your an idiot, and are blowing out HP ring and pinions, over shafts, you dont know how to drive.

Third, the D35 TTB has one more joint than a D30 solid, making it have one more weak link in the setup.

Forth, saying that the D35 -aluminum- housing, that is bolted to a sheet metal TTB arm is stronger than the fairly thick cast steel D30 housing is rediculous.

And finally, I have seen more blown out LP D44's than I have seen blown out HP D30s, the strength between the two axles is negligable, with the benefit being the bigger shafts and hubs, low pinion front axles suck and shouldnt even be considered for an offroad application.

You keep pressing this Lie, but the truth doesnt change. The D30 is every bit as stout as the D35 TTB.
 

4x4junkie

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First of all, the idea of a .030" in difference in pinion shaft diameter between the HP D35 and HP D30 having less deflection is simply rediculous, especially when you have a big pinion bearing that transfers the load before it even gets to that point.

Second, if your an idiot, and are blowing out HP ring and pinions, over shafts, you dont know how to drive.

Third, the D35 TTB has one more joint than a D30 solid, making it have one more weak link in the setup.

Forth, saying that the D35 -aluminum- housing, that is bolted to a sheet metal TTB arm is stronger than the fairly thick cast steel D30 housing is rediculous.

And finally, I have seen more blown out LP D44's than I have seen blown out HP D30s, the strength between the two axles is negligable, with the benefit being the bigger shafts and hubs, low pinion front axles suck and shouldnt even be considered for an offroad application.

You keep pressing this Lie, but the truth doesnt change. The D30 is every bit as stout as the D35 TTB.
So you're saying if you could somehow put D60 shafts into a D28 carrier, that you're an idiot if you break the gears even though the D28 is HP?
That's certainly what it sounds like since you say the idea of bigger gears being stronger is "rediculous"... :rolleyes:

Oh and I'm still waiting to see all these broken aluminum diff housings :thefinger:

The only lie here is the one based purely on speculation and opinion, not on hard facts.
 
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