Off Roading American Axle Info?

[randyn]

Hi Guys,



Just orderd my first diesel yesterday. Guy said last one came in 4 wks. Hope mine shows up quickly. Now that I finally pulled the trigger, I can hardly stand waiting... . Anyway, does anyone know anything about the front 9. 25" American Axle? I'm interested in selectable locker and or other locker w/ manual hubs... I know the new design (old?) is a non-serviceable/non-rebuildable? full time hub. Looks like it would be good candidate for aftermarket replacement hub. I don't know how you can have a hub that can't be opened up to be drained/repacked/rebuilt on a 4x4???? A hot hub driven into water is going to cool & suck water in past the seals I would think..... Eventually you'll need new bearings/seals, but as I understand, you would have to replace the whole unit $450+-???????????



RandyN

 

[rbattelle]

There is nothing to rebuild that isn't on a run-of-the-mill front-drive car. Just a hub/bearing assembly that's replaced as a unit. It's not likely there will ever be an aftermarket replacement unit for selectable locking of the hubs, since making one would also require a complete redesign of the front brakes.



Not sure how these will stand up to water, but I believe they will be easier and cheaper to replace than grenaded locking hubs.



I like it this way! Simplicity!

 

[randyn]

rbattelle



I haven't had any experience w/ Dodge locking hubs, but have '84 Toyota Landcruiser on which my 17yr old & I rebuilt the entire front axle. Never had any problems w/ those manual locking hubs. The design is simple & looks like strong enough materials & sufficient splines would prevent it from being the weak link. I like the idea of being able to unlock the front drive train to prevent unnecessary wear & improve mileage. When I used to drag race, had some figures of how much more horse power a Ford 9" , and then a Dana 60 was compared to my 12 bolt. It was a lot, I want to say something like 12 more for 9" & 20 more for the D60!! That didn't include drive shaft as it was comparing difference in differentials. If my memory is correct (right!) then there's probably about a 25 hp loss driving the front all the time. Think someone told me about aftermarket hubs for some full time 4x4, maybe someone will do that for the DTC. Looks like you could just drill out the splined hub, re-spline it larger and put in a sleeve splined inside & out that would slide in & out w/ the typical twist knob.

 

[rbattelle]

randyn,



I agree your idea for drilling out the hub/bearing assembly might work, but it wouldn't be easy. For sure, someone would have to come out with a kit for it, since custom parts would need to be machined. I fear, however, that retaining the OEM front brake disks would require a locking hub assembly of such small diameter (to still fit in the hole in the middle of the rotor), that it wouldn't be particularly strong. I could be wrong about this (wouldn't be the 1st time!). Although, now that I look at a picture of it, that hole is actually quite large.



Your comments about the horsepower loss from a full-time system such as this are, of course, quite right. There's a tradeoff the engineers have made here. On one hand, this assembly is much easier to build, maintain, and contains far fewer parts than a locking/unlocking arrangement. On the other hand, it robs a fair amount of power and fuel economy, and the maintenance rates for the u-joints up front will be much much higher.



Personally, I'm happy with the decision to move to this arrangement. I say that now, but I might change my tone the first time I have to replace all the front u-joints out-of-warranty! I also wonder about transfer case maintenance rates, since now we're spinning the front driveshaft all the time too.



Don't get me wrong, I love manual locking hubs. I installed a set on my Ranger to replace those good-for-nothing auto hubs. Manual hubs are relatively foolproof and bulletproof, as long as you're not going much over stock power (which I probably never will).

 

[randyn]

I like the manual hubs too, not keen on automatic hubs or electric transfer case. I'm really curious as to how they make (press on) the new hubs. Guess I'm really wondering if they can be pressed off & new bearings installed. I just can't visualize putting the hub on the shaft w/o a nut to adjust the preload... ... Guess I'm just not used to the "throw away parts" as opposed to serviceable parts. Humm, wonder if one could put a bearing buddy or zerk on & put new grease in... ... .

 

[rbattelle]

I used to work in an automotive parts warehouse, so I've seen lots of these hub/bearing assemblies. They're super-common on front-drive cars. They're rather large and heavy, and there's definetly no way to service them with fresh grease. The factory could, however, machine zerk fittings into them, but in today's disposable society they have decided it's easier to throw them away and install a new one.



There is a great front-view of a hub/bearing assembly on this site here:



http://www.federal-mogul.com/cda/content/front/0,2194,2442_7701,00.html



I'm with you - ease-of-maintenance is critical. Unfortunately, it seems like modern automotive engineers don't subscribe to this idea.