Differential Questions (several, and LONG)

Ace! · #1 01-30-2002, 02:27 PM

I've been contemplating the D44 or D60 thing lately (D44R/D44 or D44R/D60, front/rear). I've been told the Super44 shafts are ~40% stronger than stock shafts. On JU it's been stated:

A Dana 44 has a max torque of 6200 ft/lbs per shaft

A Ford 9" has a max torque of 6600 ft/lbs per shaft

A Dana 60 has a max torque of 9600 ft/lbs per shaft

A D44 shaft that is ~40% stronger than stock would have a max torque of almost 9000 ft/lbs per shaft. I know the above doesn't include optional spline counts for the 9" or D60, the numbers are based on 31-spline 9" and 35-spline D60, but doesn't it seem a little unbelievable that the Super44 could acheive that kind of strength? I don't know enough about the specifics of shaft design, but it just doesn't *seem* right.

The upgraded u-joints on the market (for the D30/D44)...what strength advantage is really there? Would they be equivalent to the joints typically run on a D60?

Reverse cut makes a differential, what ~30% stronger going forward (in the front)?

As a hypothetical, if you were running D60s front and rear, your next weak link would be drive shaft (yes, I've twisted a drive shaft on a vehicle, without breaking u-joints) or drive shaft u-joints? Then, transfer case shafts, or chain? If it were D44s, would it be the r&p before the rest of the drive train?

Thanks for feedback

Áron O'Proinntigh is ainm do

TObject · #2 01-30-2002, 02:49 PM

ARB

William · #3 01-30-2002, 02:53 PM

<BLOCKQUOTE>quote:<HR>Originally posted by Ace!:
I've been contemplating the D44 or D60 thing lately (D44R/D44 or D44R/D60, front/rear[/quote]

Comtemplating as in gonna purchase, or as in just thinking and gathering facts?

William "Unless you're William" Karstens
AKA
"I'm not Bill"

sethmark · #4 01-30-2002, 03:18 PM

You've been told?? Hell, I did that research. A little credit please!

Short answer is yes. Those types of shafts can reach D60 levels of strength. But as I pointed out elsewhere, thats exactly one of 1/2 dozen absolutes that determine axle strength.

Humpty Dumpty

Ace! · #5 01-30-2002, 03:27 PM

Thanks TO, but that won't fit into my plan, at least not in the front.

William, I'm not going to buy anything without at least a little research.

Besides, it seems this is the forum to get good, reliable information about stuff before making a purchase. My goal is to purchase axles front and rear, but not without knowing more about what will serve my needs. If you need more information on what my needs are before being able to talk about the strengths of the products, I'm happy to go into more detail.

Seth, I was told by someone they were ~40% stronger, and it wasn't you (unless you told me some other time and I'd forgotten). I double-checked and you were the one that posted the italicized portion of my post, previously, on JU. Credit, where credit is due

Áron O'Proinntigh is ainm dom

sethmark · #6 01-30-2002, 04:05 PM

Ace,
This making something small as strong as something big trend is a little goofy.

No matter what you do, a 9 pound stock Dana 60 shaft is just plain stronger than 4 pound Dana 44 stub. More steel is more steel. Bigger is bigger. Certainly alloy u-joints and alloy shafts help to alleviate some of the worry... but its not really a substitute.

Humpty Dumpty

TJRON · #7 01-30-2002, 04:56 PM

I don't know what the super 44 spline count is but I'm sure it's important. The super 35 does not neck down for the splines so I'd bet the D44 doesn't either. Make a custom locker to accept the larger splines and a thicker axle made of a stronger alloy and the claims might be as good as stated. I didn't even consider a super 44 for my new axle. I'm keeping my I6 and driving style so I figure if my super 35 held up I'll stick with stock D44 axles. I like the stock replacemant factor also.
As far as front axles go, I hope the Warn Hub is the weak link. If I were going big horse power I would also go with a hub conversion and the strongest I could afford of every thing else.
Numbers are not as important to me as what seems to work for others and hopefully myself.
Ron

I like the way my Jeep is now..... I'd just like it, well, a little higher off the ground with more ground clearance!

Jim M · #8 01-30-2002, 05:24 PM

The Super44 is a 33 spline unit. You are correct in that the shaft does not neck down. I'll shoot some pics in the spring when I install my disk brakes. There is also some strength in the alloy used for the shaft material.

I have never heard any of the numbers for strength of the Super44 versus a standard D44, but instead bought mine on the more is better principal. I'm not rich by any means, but got the Super44 for about $200 over a standard 44. I thought of it as good insurance that I will not need spares in my little 4 cylinder TJ.

__________________
97 TJ. Not stock.

It's only a 4 cylinder...wait up!

[This message was edited by Jim M on January 30, 2002 at 06:48 PM.]

TJRON · #9 01-30-2002, 05:45 PM

I think you made a good choice Jim. I would have done the same thing. What I neglected to add was I got the standard Ox dirt cheap so I accepted it and thought no further.

Had I known the axles in my salvaged D44 were bad and if I had to pay regular price for the OX I definitely would have gone Super.
I also wouldn't give replacements much thought if I were you. With my D35 it did lodge in my little brain when I was out places I shouldn't be, thinking what would I do if I were to break a unique axle with a c-clip rear end? It plays on the nerves as your trying to bounce up a ledge.
Ro

I like the way my Jeep is now..... I'd just like it, well, a little higher off the ground with more ground clearance!

Ace! · #10 01-30-2002, 07:56 PM

Seth, good point, bigger is bigger, but not necessarily better (although it certainly could be in this case).

Everyone around here (where I live, not this forum) is saying I need 60s, they run 60s, they break 60s. The typical response when I've asked about D44s is bwahahaha, Californians (yeah, I get a lot of good-natured crap about coming from CA sometimes) don't need big axles because they have dry rocks, which provide traction. The type of wheeling here can be 3000+ RPMs up a creek bank into a rocky wash. 3000+ RPMs to clean the mud from the tires, then hitting rocks leads to snappage. The last 3 organized runs had a minimum of 36" tires (two of those three had a minimum of 38" tires required). So, there's probably something to it, and I should probably buys 60s. I'd rather be unconventional if I can find a solution that works and is less time/money. It's also MUCH easier for me to get a TJ D44 with Super44 kit than a D60.

I'm shooting for 36" tires on dual D44s if they'll live. It seems the Super44 will be enough, but I'm not sure. The numbers seem pretty impressive, and if they're based in reality I think it'll work for me if I'm careful. I just wanted to get some perspective from some people about whether a D44 shaft could be made as strong as advertised. A D30 can't be made to live up front with this style of driving, but if the r&p were rc and D44-sized they'd be much stronger than the standard D30, then I'd be wondering about the u-joint (CTM or OX), and what else is liable to fail next. Although, maybe it boils down to *needing* D60s front and rear (that's to what experience around here would seem to point)

Áron O'Proinntigh is ainm do

Jim M · #11 01-30-2002, 08:07 PM

Ace!,

Might I recommend some passenger seat time? It seems that it would be beneficial to make some friends and get out onto the trails and see what's available. Listening to the locals and gathering information to make a decision is good, but nothing beats first hand experience. With your background being possibly different than the native's in the area, you may bring a fresh perspective to the running techniques on local trails. Go forth and volunteer to pull winch cable for a few runs and see what's _really_ out there.

__________________
97 TJ. Not stock.

It's only a 4 cylinder...wait up!

TJRON · #12 01-30-2002, 08:08 PM

Everone around where you live is full of ****.

Ron

I like the way my Jeep is now..... I'd just like it, well, a little higher off the ground with more ground clearance!

Ace! · #13 01-30-2002, 09:02 PM

Thanks for the advice Jim. I've got over a year of wheeling here, plenty of passenger seat time too (I don't take my Jeep on runs where 36"+ tires are required)

I'm asking the questions that are relevant to my situation. YMMV.

sethmark · #14 01-30-2002, 09:04 PM

Its pretty simple really. The parts have got to be stronger than the torque.

If the torque overwhelms the parts, they break. Maybe not the first time, but eventually you pass the threshold.

Hence 1 ton axles in 1/4 ton applications.

Humpty Dumpty

Ace! · #15 01-30-2002, 09:06 PM

Thanks Seth. I understand there's a reason D60s are popular in some areas, and not in others, so I figured it'd do me well to ask about the various set ups.

Áron O'Proinntigh is ainm dom

Robert J. Yates · #16 01-31-2002, 08:18 AM

<BLOCKQUOTE>quote:<HR>Originally posted by Seth:

This making something small as strong as something big trend is a little goofy.

[/quote]

Hmmm, yes and no. Using this logic would mean that for you to type this out and post it, you should be sitting behind a VAX computer the size of your living room with the brain power of a 8088 machine. The world is full of examples of stuff that used to be big getting made into stuff that is now smaller but performs at a comparable level. Yes for certain size tires in certain wheeling situations you will need 60's but does every Jeeper need 60's and full one ton running gear, no.

98 TJ Sport
D44ARB/D30Detroit/Teralow/35" MTr's

TJRON · #17 01-31-2002, 08:57 AM

<BLOCKQUOTE>quote:<HR>Originally posted by Robert J. Yates:
Yes for certain size tires in certain wheeling situations you will need 60's but does every Jeeper need 60's and full one ton running gear, no.

[/quote]

Every Jeeper in Oregon needs 60s and at least 1 ton running gear. You SC boys can get by with 31s and 1/2 ton stuff. Us Nevadans need even less.

I like the way my Jeep is now..... I'd just like it, well, a little higher off the ground with more ground clearance!

sethmark · #18 01-31-2002, 09:34 AM

<BLOCKQUOTE>quote:<HR>Originally posted by Robert J. Yates:
Quote: "Originally posted by Seth:

This making something small as strong as something big trend is a little goofy.

"

Hmmm, yes and no. Using this logic would mean that for you to type this out and post it, you should be sitting behind a VAX computer the size of your living room with the brain power of a 8088 machine. The world is full of examples of stuff that used to be big getting made into stuff that is now smaller but performs at a comparable level. Yes for certain size tires in certain wheeling situations you will need 60's but does every Jeeper need 60's and full one ton running gear, no.

98 TJ Sport
D44ARB/D30Detroit/Teralow/35" MTr's

[/quote]

You know what I mean! Sigh.

Humpty Dumpty

William · #19 01-31-2002, 09:57 AM

<BLOCKQUOTE>quote:<HR>Originally posted by TJRON:
Every Jeeper in Oregon needs 60s and at least 1 ton running gear. You SC boys can get by with 31s and 1/2 ton stuff. Us Nevadans need even less.

[/quote]

235/75r14'S and an inflatable sheep, right??

William "Unless you're William" Karstens
AKA
"I'm not Bill"

Ace! · #20 01-31-2002, 10:10 AM

It seems some have gotten a laugh out of the California comment. I didn't mean anything by it, as it's something that's been said to me. I don't know how it translates to Nevadans

. I've wheeled for 15 years and never needed anything stronger than a D44 (I never broke a D44). That's what prompted my question. I'm not comparing one kind of wheeling with another in an attempt to say one is bigger or badder than another, I'm just in a bit different environment than I have wheeled for the past 15 years in California and was hoping to get a little info/perspective from some people I trust here (on this forum). People around here (Oregon) run 60s because they break 44s, I was just hoping to find a more economical way to run a 44 and still find the strength to run the trails I want to run. Bottom line is I build based on where I want to go, and what I can afford. With a little help I figure I can find another solution that works as well as 60s, but maybe there isn't one.

Most of the rigs around here do run 1-ton running gear, and most are full-size, not Jeeps. This is the short synopsis of the last run (which I didn't go on because I didn't meet the minimum trail requirements and didn't feel like getting covered in mud):

"5 confirmed roll-overs, one Wrangler had a truly bad day. The bellhousing broke away from the engine and the engine went out through the radiator and grill…. There were Jeeps leashed to trees everywhere as there owners were frantically changing out broken axles."

This is a pic of the last run, the guy in the front, in the red YJ is running a 39.5" tall tire:

Áron O'Proinntigh is ainm dom

Robert J. Yates · #21 01-31-2002, 10:19 AM

<BLOCKQUOTE>quote:<HR>Originally posted by Seth:

You know what I mean! Sigh. [/quote]

No, not sure that I do - remember this?

Might be driver... I have 1 Moab trip, somewhere in the low 20s in Rubicon trips, and various trips to Truckhaven, Ocotillo Wells, Pismo Beach, Bronco Hill, about a dozen trips to hollister and 60k road miles and have never broken the stock 30.

or this?

Blaine,
I've been carrying the same 2 sets of spare front axles around for so long they're getting dusty!

or this?

Seth (another ardent D30 supporter, but not willing to spend any money on it)

From this thread;
http://jeepbbs.atinfopop.com/4/OpenT...5&m=7954099921

Gotta love the search feature eh

98 TJ Sport
D44ARB/D30Detroit/Teralow/35" MTr's

sethmark · #22 01-31-2002, 11:02 AM

You know what? It ALL still applies. Every freakin' word of it. Why??? Because I do not overload my rig. I don't force lines or depend on wheel speed to compensate. I operate my equipment within its limits.

Axles are black and white. The load ranges and torque specs are fixed in steel. If you're not exceeding the specs, you don't get failure.

The limits are determined by the chemistry of the metals. I bet the CTM u-joint never fails. Ya know why? Cuz its just plain stronger than the yokes its attached to. Does that make a Dana 44 equal a dana 60? **** no. What it does is make a better 44.

Humpty Dumpty

[This message was edited by Seth on January 31, 2002 at 12:27 PM.]

Ace! · #23 01-31-2002, 11:18 AM

Seth, either you meant to address that to someone else, or I don't understand what part you think I'm throwing back at you??? Can you explain what part of your words I'm throwing back at you?

I was asking about the specifics of the axle construction, to better understand the limits. I don't think I've said, or asked about too much else.

Áron O'Proinntigh is ainm dom

sethmark · #24 01-31-2002, 11:28 AM

I editted... Whoops.

My typing is sounding far more agressive and ****y than I'm intending.

Sorry.
Humpty Dumpty

TJRON · #25 01-31-2002, 11:43 AM

<BLOCKQUOTE>quote:<HR>Originally posted by Ace!:
....The type of wheeling here can be 3000+ RPMs up a creek bank into a rocky wash. 3000+ RPMs to clean the mud from the tires, then hitting rocks leads to snappage. The last 3 organized runs had a minimum of 36" tires (two of those three had a minimum of 38" tires required).

.....Most of the rigs around here do run 1-ton running gear, and most are full-size, not Jeeps.......

......5 confirmed roll-overs, one Wrangler had a truly bad day. The bellhousing broke away from the engine and the engine went out through the radiator and grill…. There were Jeeps leashed to trees everywhere as there owners were frantically changing out broken axles."

[/quote]

I know a few of these types and they're definitely not Jeepers. In fact they laugh at Jeeps. They are usually fabricators with access to junk yards and get their kicks tearing stuff up.

If I were you I would find a Jeep club or start with another vehicle.

That picture looks like total misery to me.......

Ron

I like the way my Jeep is now..... I'd just like it, well, a little higher off the ground with more ground clearance!

Art Welch · #26 01-31-2002, 12:00 PM

When things get wet things change quite a bit. I grew up in Oregon and can vouch for the fact that the wheeling there is nothing like it is in the Southwest. In the area we used to go without wheel speed you went nowhere regardless of tires or lockers. Unfortunately more wheel speed means more breakage, even in a jeep.

Robert J. Yates · #27 01-31-2002, 12:00 PM

<BLOCKQUOTE>quote:<HR>Originally posted by Seth:
.....that make a Dana 44 equal a dana 60? **** no. What it does is make a better 44.

[/quote]

Ok, now we are at the heart of the discussion - read my first response. I said I don't believe that every Jeeper out there needs 60's. But, I could have easily added the fact that this is probably true when a better, say upgraded D44 (with say Superior chrome moly axle shafts for the rear or CTM D300 ujoints with Warn high strenght axle shafts for the front) for example will serve their needs just fine on 35, 36 or maybe 37 inch tires. Personally, with a straight 6 and lots of rocks, I think a 60 is nothing other than a hinderance unless you begin engineering the lift of the Jeep to run at least 38 inch tires so you can clear the diffs to get through the rocks.

Yea, in wet crappy environments where folks are running big V8's, 60s are probably big consideration but frankly, I think even in that environment, its a stretch as you certainly do not need a V8 to run there and there are certainly alot of Jeeps running around that did not come with V8's.

And back to the lift to run 1 ton gear, I think that folks running 60s, particularly in TJ's need to really work at it to make it perform. If somebody is going to run 38's, my opinion is that they better be planning on extending the rigs' wheelbase by moving the axles to the front and rear of the Jeep to get some wheelbase. Other-wise, space is tight and things can get interesting from a COG point of view, not to mention anti dive and anti squat issues when climbing or breaking.

I know you weren't being ****y Seth and I hope you know that neither was I attacking you - just having a friendly discussion is all

98 TJ Sport
D44ARB/D30Detroit/Teralow/35" MTr's

sethmark · #28 01-31-2002, 12:19 PM

Nod. I agree. 60's are NOT for everyone... and I don't think anywhere I tried to sell anyone on them.

I also agree that unshaved 60s are a hinderance in big rocks, as every inch counts, particularly without 38"+ sized tires.

Now I agree that the alloy shafts and indestructo u-joints help small axles stay alive in adverse conditions. But my point is that at a certain point there is no susbtitute for sheer size. If alloy u-joints and shafts in a 44 are x strong.. think about that same alloy in a 60.

Additionally, we ALL know people that have killed the D30 and D44s. U joints break. Lots of them. I personally know of 5 sets of Dana 30 ring gears that have died. 2 of them frequent this board. I know of TONS of 'hi strength' warn front axles that have exploded.

Whats my point? As I've recently learned, mostly by seeing a lot of broken parts is that more steel in yoke, u-joints, shafts, tubes, etc... promote longevity in abused vehicles.

Humpty Dumpty

William · #29 01-31-2002, 12:32 PM

It appears that the red YJ doesn't have the front locker engaged, as evidence by one madly spinning wheel, and one sitting there.

William "Unless you're William" Karstens
AKA
"I'm not Bill"

Art Welch · #30 01-31-2002, 12:38 PM

<BLOCKQUOTE>quote:<HR>Originally posted by Robert J. Yates:
And back to the lift to run 1 ton gear, I think that folks running 60s, particularly in TJ's need to really work at it to make it perform. If somebody is going to run 38's, my opinion is that they better be planning on extending the rigs' wheelbase by moving the axles to the front and rear of the Jeep to get some wheelbase. Other-wise, space is tight and things can get interesting from a COG point of view, not to mention anti dive and anti squat issues when climbing or breaking.
[/quote]

I agree with you 100% Robert. I'm on the verge of needing to do just this like we had talked about and frankly if I had realized up front the need to take these additional steps I may very well have taken a different upgrade path. Yeah, it will be really cool to have a longer wheelbase TJ with a custom 3 link but at this point I would be happy to just be out wheeling.

I don't think I would have stayed with a 44 necessarily since my experience tells me that in the stuff I like to do it won't stand up to wheel speed when it's needed, but that huge pumpkin on a 60 is a pain in the ass whether it's shaved or not.