TJ Manual hub question?
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1stDeuce
Explorer
Stubs, bearings, and hubs from a Ranger/BII or Explorer?? Just a little more info please. And add early Grand Cherokee and Comanche to the list of fits as well!!
Word of caution... The t-cases that came in Jeeps with a CAD axle had a bearing on the chain sprocket where it rides on the mainshaft. This because the front prop, and hence chain and sprocket, weren't turning in 2wd, while the mainshaft was going road speed. When Jeep took the CAD growth off the axle, they took the bearing out of that gear, and it's just steel on steel... Not much relative motion, as the sprocket and chain are normally turning about the same speed. Might want to consider finding an older sprocket that'll take the bearing if you put a lot of miles on with hubs unlocked. Mainshaft didn't change, and the older sprocket will swap right in.
C
Word of caution... The t-cases that came in Jeeps with a CAD axle had a bearing on the chain sprocket where it rides on the mainshaft. This because the front prop, and hence chain and sprocket, weren't turning in 2wd, while the mainshaft was going road speed. When Jeep took the CAD growth off the axle, they took the bearing out of that gear, and it's just steel on steel... Not much relative motion, as the sprocket and chain are normally turning about the same speed. Might want to consider finding an older sprocket that'll take the bearing if you put a lot of miles on with hubs unlocked. Mainshaft didn't change, and the older sprocket will swap right in.
C
jeepdreamer
Expedition Leader
Sounds like a good idea to me. I'd say (generally speaking, no offense to anyone meant) most folks rockin' their Dana 30 are not likely to be I'n the over-extreme category. Maybe the 35" tire and smaller? So a hub upgrade that's affordable really makes sense! If i was gonna drop 2k on my front axle it would be at least a 44! But for folks that wheel smart, don't have big bucks, or already have to much invested to start over then this sounds great!! Good luck! 
reece146
Automotive Artist
What is the problem you are trying to solve with manual hubs?
I have manual hubs on the D30 in one of my Jeeps.
You will not save any appreciable MPG if the Jeep is built up at all. If that is the reason for doing this modification I'd have a serious rethink about it.
If it's serviceability... pulling a shaft on a uni-bearing axle is a lot less fuss than an old fashioned axle with manual hubs. If you are trying to reduce costs because uni-bearings are "expensive" then I think for the sake of say $100 per side per uni-bearing service window this is a lot of fuss for very little gain.
If it's "because you can" then have at it.
2¢
I have manual hubs on the D30 in one of my Jeeps.
You will not save any appreciable MPG if the Jeep is built up at all. If that is the reason for doing this modification I'd have a serious rethink about it.
If it's serviceability... pulling a shaft on a uni-bearing axle is a lot less fuss than an old fashioned axle with manual hubs. If you are trying to reduce costs because uni-bearings are "expensive" then I think for the sake of say $100 per side per uni-bearing service window this is a lot of fuss for very little gain.
If it's "because you can" then have at it.
2¢
BigAl
Expedition Leader
1. If you have manual hubs, you can have a real bombproof front locker, and still steer. Otherwise you must go selectable which is more money and arguably less reliable.
2. If you break an axle shaft with manual hubs you just unlock and drive home, I did that this summer
3. yes it is cooler
What I have come up with also moves the bearings out more as well. This gets them out of the knuckle and into the center line of the wheel, which should put a lot less stress on the bearings.
Also the ability to unlock the hubs should eliminate a bunch of wear on axles,driveshafts,lockers etc in the front.
Also the ability to unlock the hubs should eliminate a bunch of wear on axles,driveshafts,lockers etc in the front.
1stDeuce
Explorer
Sounds cool. I did the math and thinking and ended up deciding against it, but I would LOVE to get out and "Lock 'er in!" at the trailhead, just for nostalga's sake. As-is, my unit bearings are doing fine, and I can R&R an axle shaft in about 20 minutes on the trail, with no grease mess or small parts to loose track of. Hmm... could keep the unit bearing, but bore it for the longer stub, then use the locking hub to get drive... Aaaah, what am I thinking???
And to clarify about the t-case, if you have a normal TJ, in 2wd, the chain is still spinning because it's driven by the driveshaft. Everything is still spinning, really, just like in 4wd, it's just not coupled solidly to the mainshaft. Therefore no relaitve speed difference, vs when you go CAD or hubs unlocked, the driveshaft and chain stop spinning, and the sprocket rides (stopped) on the spinning main shaft. Probably no big deal on a low mileage wheeling rig, but a highway cruiser might burn thing up with the high speed metal-on-metal that's going on. ?? Hmm, now that I think about it, I think the newer GM trucks with NV t-cases are metal on metal with no bearing, and they live fine with a CAD setup... I think I'm worrying you about nothing. Back to your design work!!
C
And to clarify about the t-case, if you have a normal TJ, in 2wd, the chain is still spinning because it's driven by the driveshaft. Everything is still spinning, really, just like in 4wd, it's just not coupled solidly to the mainshaft. Therefore no relaitve speed difference, vs when you go CAD or hubs unlocked, the driveshaft and chain stop spinning, and the sprocket rides (stopped) on the spinning main shaft. Probably no big deal on a low mileage wheeling rig, but a highway cruiser might burn thing up with the high speed metal-on-metal that's going on. ?? Hmm, now that I think about it, I think the newer GM trucks with NV t-cases are metal on metal with no bearing, and they live fine with a CAD setup... I think I'm worrying you about nothing. Back to your design work!!
C
jeepdreamer
Expedition Leader
thoughts..
I don't believe they are the same but you'll want to research that.First thing that comes to mind is checking ball jpint numbers? If they use the same ball joints then maybe they are not so different? TREs maybe be different as well. I know terraflex (and others) made a complete new casting to create a hysteer application for the 30, maybe you could cross reference parts via a call to them? Or try giving Parts Mike a call and talk directly to Mike. The rest of the guys working there have a long way to go to catch up to his smarts.
I know some bring up the "why" of doing this. Personally I prefer the servicability of "real" bearings over uni ones. I also don't like that with a uni there can be zero failure warning prior to wheel seperation. The fact that manufacturers went this way as a cost and time savings doesn't make me very excited either. Do servicable bearings require attention? Sure. But I prefer them anyway. Good luck with your creation!
I don't believe they are the same but you'll want to research that.First thing that comes to mind is checking ball jpint numbers? If they use the same ball joints then maybe they are not so different? TREs maybe be different as well. I know terraflex (and others) made a complete new casting to create a hysteer application for the 30, maybe you could cross reference parts via a call to them? Or try giving Parts Mike a call and talk directly to Mike. The rest of the guys working there have a long way to go to catch up to his smarts.
I know some bring up the "why" of doing this. Personally I prefer the servicability of "real" bearings over uni ones. I also don't like that with a uni there can be zero failure warning prior to wheel seperation. The fact that manufacturers went this way as a cost and time savings doesn't make me very excited either. Do servicable bearings require attention? Sure. But I prefer them anyway. Good luck with your creation!
jeepdreamer
Expedition Leader
kinda...
After a little thought I'd say generally, yes, Dana 30 and 44 KNUCKLES do not interchange.
But some of the hub related stuff does... kinda. My Scout dana 44 runs flat top waggy 44 knuckles but the spindles came from my dana 30 from my CJ. And IIRC there are a couple different size bearings to play with both inner and outer as well as the inner seal sizes.
After a little thought I'd say generally, yes, Dana 30 and 44 KNUCKLES do not interchange.
But some of the hub related stuff does... kinda. My Scout dana 44 runs flat top waggy 44 knuckles but the spindles came from my dana 30 from my CJ. And IIRC there are a couple different size bearings to play with both inner and outer as well as the inner seal sizes.
reece146
Automotive Artist
The Scout Dana 44 is a hybrid axle of sorts.
The spindle assembly itself is Dana 30. I forget what is different between the Scout and Jeep Dana 30 (if anything). I think if there is a difference the Scout II version uses the same parts as the Scout 800 (versus Jeep Universal).
The Scout II knuckle is an IH specific Dana 44 casting that shares the same ball joint geometry as a "traditional" Dana 44 knuckle. I believe IH did this to enable the scrub radius to be as small as practical while using off the shelf parts and share shelf-ware with the older Dana 30 axles under the earlier Scouts. The small scrub radius is too convenient to have been an accident.
The Scout II brakes are unique as well. IIRC they are the largest single piston callipers and rotors ever fit to a Dana 44.
There is a lot of good detail engineering in the Scout Dana 44. Those engi'nerds at IH knew what they were doing.
The big deal about Dana 30 and Dana 44 knuckle swapping is the inner "C" on the axle tube itself. The C is different between 30s and 44s. The Scout II axle uses a Dana 44 inner C hence you can use a "true" Dana 44 knuckle to built from. I have a pile of parts to build an axle for my Wrangler when I get around to it (F250 HP Dana 44 housing with Chevy flat tops and Scout spindles/hubs/brakes).
If you search over at Pirate you can find Bill Ansell's old build of a hybrid axle using a XJ Dana 30 housing and replacing the C's on the housing to be Dana 44 units.
The spindle assembly itself is Dana 30. I forget what is different between the Scout and Jeep Dana 30 (if anything). I think if there is a difference the Scout II version uses the same parts as the Scout 800 (versus Jeep Universal).
The Scout II knuckle is an IH specific Dana 44 casting that shares the same ball joint geometry as a "traditional" Dana 44 knuckle. I believe IH did this to enable the scrub radius to be as small as practical while using off the shelf parts and share shelf-ware with the older Dana 30 axles under the earlier Scouts. The small scrub radius is too convenient to have been an accident.
The Scout II brakes are unique as well. IIRC they are the largest single piston callipers and rotors ever fit to a Dana 44.
There is a lot of good detail engineering in the Scout Dana 44. Those engi'nerds at IH knew what they were doing.
The big deal about Dana 30 and Dana 44 knuckle swapping is the inner "C" on the axle tube itself. The C is different between 30s and 44s. The Scout II axle uses a Dana 44 inner C hence you can use a "true" Dana 44 knuckle to built from. I have a pile of parts to build an axle for my Wrangler when I get around to it (F250 HP Dana 44 housing with Chevy flat tops and Scout spindles/hubs/brakes).
If you search over at Pirate you can find Bill Ansell's old build of a hybrid axle using a XJ Dana 30 housing and replacing the C's on the housing to be Dana 44 units.
Dan Grec
Expedition Leader
After driving my little TJ 65,000kms on some of the worst roads you can imagine, I was shocked on the weekend when my buddy driving his 4runner had me get out in the pouring rain to lock in the hubs because we were sinking in the mud.
I too sank up to my knees, and the front hubs were basically underwater/mud.
IMHO locking hubs are a pain in the ***.
-Dan
The conversion only replaces the unit bearing and the axle shaft and the spindle. Not the knuckle which is interchangeable on the jeep 44 and 30. I guess it is not for everybody but I personally don't like things I can't grease and spinning the axles all the time bothers me.