Engine/Transmission (1998.5 - 2002) Front axle disconnect gone

[rspinks]

front driveshaft coupling

Jason,



I saw some info somewhere on a coupling-type device that is added to one end of the front driveshaft via shortening the original shaft. The coupling has enough play designed into it to compensate for the speed differential between the front halfshafts when turning in 4wd.



I thought this was a smart and affordable idea that would effectively let you turn in 4wd without the driveline-stressing frontend hop. The downside potentially would be how much slop you could you feel during normal 4wd driving. I would search for this thing but can't remember what it's called.



RS

 

[ZEEEW]

The speed difference between the front shafts is already taken care of by the front dif, if it is an open dif. The speed difference when turning is from the front and rear axles, which can be taken care of by a transfer case with a dif or limited slip. Course this isnt "real" 4 wheel drive either.

I do like the ability to use 2 low from bypassing the vacuum switch, havent done it yet though.

This is only my opinion of course, would rather have good old manual hubs, but i still feel that, even if only the spiders were turning, the disconnect is harder on the front end than the whole front end turning as a unit. Through parasite drag, it almost is anyway.

How would you shift on the fly if the transfer case, not to mention the axle ends, werent at close to the same speed? To my knowledge there are no synchros in the transfer case, though I could be wrong here, havent been into mine. I am willing to bet, though, that if you look at one of our trucks going down the road, you will see the front axle turning, even in two wheel drive.

My opinion is the disconnect is a unneeded weak link.

These are opinions only!

 

[Jeff Knight]

The 02 gas trucks still have the disconnect. I think the axle is stronger without the two piece axle on the right side. Plus it's a one piece axle tube. Just my . 02 Jeff

 

[rspinks]

coupling

Zeeew you are right, my explanation was incorrect. I guess the loose coupling allows for speed differences between the front and rear driveshafts. This makes more sense.

 

[JHansen]

Rich-I know exactly what you are talking about. Milemarker makes it-it's basically (or exactly!) a viscous coupling to allow speed differential between the front and rear axles. Only downside is there is no way to lock it solid for true off-highway 4x4 usage-which I pretty much gotta have. So onward down the 242 swap road I forge!



Like I said previously-I may find that I can explode it at will no matter how much beefing I do. If I do-rest assured I'll slink back into here with my tail between my legs and admit that it was a poor idea. Hopefully that doesn't happen-I really hate crawling!



J

 

[MidwestMotorman]

anybody do the twin stick trick???

Anybody doing the twin stick transfer case trick? If you want 2LO, that should let you do it without having the disconnect. I agree that a disconnect is handy, but I am very weary of going off-roading on rough terrain with a split-tube front end. I have seen lots of them that take a hard beating and end up in two.



Not to mention that the right side wheel will eat the fenders, floorpan, inner ac box, and other vital expensive parts when it comes apart. :{

 

[EricBu12]

I have the diconnect style and as far a sturdy, I did the truck pull at May madness and I pulled 232' and 176' and nothing broke. (thank God)

Did better than I thought I would

 

[rspinks]

Milemarker Selective Drive

Jason, thanks! I read about this coupling at www.milemarker.com (under the 4x2 section of the catalog?) and now I'm more interested. They state it's not a viscous coupling, and the picture to me looks very much like a mechanical locker.



They say it's "proven in off-road racing" which begs further investigation. In desert racing they're running 800hp big-block 4x4's, sometimes on pavement sections. Wouldn't that be cool if this coupling was strong enough to survive that!

 

[JHansen]

Somewhere Rich I have an article on this when it was first introduced. I could have sworn they said it was viscous coupled-but I could be wrong. Like I said-it's not for me as I need the ability to lock everything totally solid at will. But for others it should work great! It's been around for quite a while now so it must work as it's supposed to.



Jason

 

[MidwestMotorman]

issue 32 page 60

You can find a write-up on the select drive in TDR issue 32 starting on page 60.

 

[jberelson]

Looked under truck this morning... still has disconnect on right side...



Josh

 

[MidwestMotorman]

My grandfather's 02 built in 2/02 has no disconnect. I also noticed that the load sensing brake valve for the rear is gone too. Must not need it with four wheel discs. Those four wheel discs really seemed to work good, but I noticed the backside of one of the rear rotors was already grooved from something. Don't know what, but it had more than one groove that would easily hang up a fingernail.

 

[cmccracken]

Sorry to drag up an old thread, but I was wondering if anyone had messed with fitting manual hubs on one of the newer 02's with the CAD (that's what I have). Someone said it may be possible by fitting some older steering knuckles, but I couldn't find anymore on that idea. Also, I've read from several sources that you shouldn't use an LSD in the front because of the CAD system. I don't have the CAD, so would an LSD work out ok (Detroit Locker in mind)? Would that require manual disconnect hubs to keep from binding on pavement? I'll admit that I don't fully understand what makes the Detroit engage/disengage. Intended use for locker is offroading. ARB will be much more $$$ if something else won't work out.

 

[fest3er]

I'd like to toss in my tuppence of opinion.

A drawback to having no CAD is the front D/S is always turning now - slightly more power loss.

However, a *large* advantage to having no CAD is that allt he parts are always turning. This means that lubes are always being churned and moved, keeping the parts properly lubed. Considering the cost of tearing the front end apart to replace axle u-joints and other components, it really *is* better to have the parts always turning and lubed.

Of course, if we had front hubs, it would be easy to engage 4WD once or twice a week without the hubs locked. In the summer, this would likely be enough to keep the parts lubed.

If the parts don't remain lubed, they can hang up, interfering with steering, something I experienced with my old F150.

IMHO.

Fest3er

 

[Mopar-muscle]

fest3er , did your old ford have the manual hubs ? way back when i was looking for my first 4 wheel drive i looked at a used ford . it had manual hubs , i locked them and put it in 4wheel , made all kinds of god awful noises . with manual hubs the u joints aren't turning all the time and if you don't use 4whl they end up siezing prematurly i believe . so at least with ours turning all the time the u joints last a tad longer ? 88k on mine .

 

[Pit Bull]

Back in 1984 my wife bought a Toyota 4x4, it had the locking hubs. I would lock them for a few miles every 3-4 months just to keep everything lubed. She sold it after putting over 150K miles on it. Nothing ever broke or wore out on that truck. Well I did bend the rear bumper a little pullin a stump out of the ground. She made me pay to fix it I bet I could really pull some big stumps out of the ground with this CTD

 

[Cummins Cowboy]

Ok i can understand wanting to have the ability to have the transfer case shift down to a lower gear ie backing trailers up steep hills, My question is this why is having 2wd low important. Why not just shift into 4wd low as usual and back that trailer as needed. That is what i did the other day with my trailer and no problems, plus i think it is good to engage 4wd every so often anyways.

 

[MidwestMotorman]

the cramping

Backing up a trailer in 4wd is not bad as long as one is on loose surfaces. Tight turning on hard surfaces of the front wheels while powering them causes a "cramping" effect. The longer the rig, the worse it is. The tighter the steering is turned, the more wear and force is applied to the inner u-joints and drive components. Combine that with a manual trans, sensitive throttle, heavy load, and one ends up with the annoying cramping and jerking while trying to manuever a trailer. Having the front axle not engage makes it much easier. Just like a 2wd truck with a low gearing.

 

[fest3er]

Originally posted by Mopar-muscle
fest3er , did your old ford have the manual hubs ? way back when i was looking for my first 4 wheel drive i looked at a used ford . it had manual hubs , i locked them and put it in 4wheel , made all kinds of god awful noises . with manual hubs the u joints aren't turning all the time and if you don't use 4whl they end up siezing prematurly i believe . so at least with ours turning all the time the u joints last a tad longer ? 88k on mine .

Yes, it had manual hubs. And yes, it eventually did exactly what you described. Or worse!

Fest3er

 

[rujpn2]

As of whether or not the disconnect being gone is good or bad for wear, only time will tell. Without the disconnect, it becomes one axleshaft on the long side of the tube. With the Dana 60, the disconnect axle had a shaft that was smaller than (or equal to) a Dana 44 shaft. The one piece design is 1. 5" in diameter.



Dynatrac makes a kit to conver the disconnect axle to hubs. It does this by making a new long shaft that is tapered to fit through the disconnect section. You get hubs, but not a larger diameter shaft.



The front of the new Dana 60 is a ball joint at the knuckle. If you can find a previous Dana 60 that is ball joint (there is a king pin style too) that will use the same joints, you could change it out and run manual hubs. Would have to see how to adapt the tone rings for the ABS to the new knuckle. I just bought my truck, so I have not had the tires off, yet. If it is not a unit bearing setup like the current Super Duties, you might just have to change out the bearing plates and the the outer shaft. If the tone ring for the ABS is mounted on the outer shaft, will have to get it to go onto the new shaft.



Dynatrac would probably be the best bet of who to talk to about converting to hubs for either style axle.



Nothing to say which is better for wear, just showin' how the new style is stronger.



hth

Greg