Auto vs AManual hubs

[Houndoc]

On a Montero Sport board, a debate is raging over the wisdom of "upgrading" to manual hubs instead of auto. Too me that is a jump back in time, not upgrading, but could be off-base.

Comments like this "Of course if your only doing easy trails you can just wait until they go bad then upgrade to manual hubs when they do.

On the other hand, if you're doing hard core trails most wheelers who are regulars will tell you to remove the auto's and put in manual hubs so they don't have to strap you out because you only have 2WD. " come from the pro-manual hub group, along with tales of improved gas milage, less front end wear and problems with auto hubs "popping out" of 4WD when backing up.

What are some thoughts here? (to be honest, the MS board is not an off-roader haven.)

 

[I Lean]

On a Montero Sport board, a debate is raging over the wisdom of "upgrading" to manual hubs instead of auto. Too me that is a jump back in time, not upgrading, but could be off-base.

Comments like this "Of course if your only doing easy trails you can just wait until they go bad then upgrade to manual hubs when they do.

On the other hand, if you're doing hard core trails most wheelers who are regulars will tell you to remove the auto's and put in manual hubs so they don't have to strap you out because you only have 2WD. " come from the pro-manual hub group, along with tales of improved gas milage, less front end wear and problems with auto hubs "popping out" of 4WD when backing up.

What are some thoughts here? (to be honest, the MS board is not an off-roader haven.)

The "upgrade" isn't in the ease of use necessarily, it's the longevity and reliability. Auto hubs don't always work as they should, when they should, and they tend to get worse over time. That's where the reference to "only having 2WD" comes from. It's WAY better to have to get out of your cushy seat to lock the hubs when you need to, than having no way of locking your front end if your auto hubs don't work or break.

 

[1993yj]

Manual hubs are generally considered to be stronger as well. That said, I dont run them on my rig, but who wants to spend $900 for the Warn conversion kit on a Dana 30? Not me. Although I figure I will break u-joints and shafts and probably the housing before I break anything else.

 

[Tacoma]

x3 on strength.

That said, the auto hubs in the Burb are pretty nice, because dang it those seats ARE comfy. And the Burb is warm. Plus, it's nice for icy roads.

 

[timpanogos]

lost my 4wd on my 2003 (or so) gmc 3/4 ton pickum up truck. I need to get this fixed ... how do those auto jobbies work anyway? Is there a small motor or solenoid, if so where are these located?

 

[78mitsu]

Most manual hubs are a ball and ramp hub. if it's this design, it means that when the axle turns, it has to make almost a full revolution before that hub is engaged and then a full revolution again to engage the other hub, same thing in reverse only now it's 4 turns 2 to disenguage 2 to engage, and there are lots of small moving parts. if it's rather inexpensive it's worth the investment.

 

[timpanogos]

Most manual hubs are a ball and ramp hub. if it's this design, it means that when the axle turns, it has to make almost a full revolution before that hub is engaged and then a full revolution again to engage the other hub, same thing in reverse only now it's 4 turns 2 to disenguage 2 to engage, and there are lots of small moving parts. if it's rather inexpensive it's worth the investment.

I assume you mean "Most auto hubs..." So there is no electrical deal to the auto? It's just a matter of engaging the transfer case and the drive line turning causes the unit to mechanically engage?

So if one has no 4 wheel drive, do the "lots of small moving parts" tend to be broken, or just frozen up? Are all of these magic parts physically in the hub?
What do I tear down and check for?

 

[Meat_]

lost my 4wd on my 2003 (or so) gmc 3/4 ton pickum up truck. I need to get this fixed ... how do those auto jobbies work anyway? Is there a small motor or solenoid, if so where are these located?

I coulda swore that was a Dodge I was riding in

 

[timpanogos]

My 2nd son is starting up his own concrete business ... kind of how I justified my new ram. Anyway he got the old gmc, and I would like to get the 4x4 working for him. Transfer case seems to switch in ok ... mechanical ... I figured there was some switch in there that did the auto lock of the hubs ... but guess it's all mechanical??

 

[Meat_]

It's vacuum, as to what gets sucked, I'm not sure

Typically what goes wrong on those Chevs is the vacuum thingy... or a line gets pulled off.

 

[78mitsu]

I assume you mean "Most auto hubs..." So there is no electrical deal to the auto? It's just a matter of engaging the transfer case and the drive line turning causes the unit to mechanically engage?

So if one has no 4 wheel drive, do the "lots of small moving parts" tend to be broken, or just frozen up? Are all of these magic parts physically in the hub?
What do I tear down and check for?

yes, Most electric hubs aren't actually hubs, it's a viscous coupler somewhere in the front axle tube. The axles turn in the front full time, but one side doesn't actually reach the diff, because it's disconnected.

 

[Houndoc]

Manual hubs are generally considered to be stronger as well......Although I figure I will break u-joints and shafts and probably the housing before I break anything else.

To me that, is the real question. Are they truely the weak link?

Has anyone here actually had them fail?

 

[mbryson]

To me that, is the real question. Are they truely the weak link?

Has anyone here actually had them fail?

I've had the older Chev units not work before.

 

[timpanogos]

mines not working -- 1992'ish 3/4 ton

 

[mbryson]

mines not working -- 1992'ish 3/4 ton

I think that's a axle disconnect thingy. I don't think the IFS trucks had hubs at all (kinda Jeep, drivers drop Dodge like)

 

[Tacoma]

You know, this has me thinking. I really have no idea how the hubs work on the Burb. I don't think there's any vacuum in play. Will have to take a close look this weekend.

 

[mbryson]

You know, this has me thinking. I really have no idea how the hubs work on the Burb. I don't think there's any vacuum in play. Will have to take a close look this weekend.

No vacuum on those babies. I think they're a centrifigal force thing. They're the kind I've had issue with in the past (from what I understand, a cleaning makes them work better).

 

[Meat_]

To me that, is the real question. Are they truely the weak link?

Has anyone here actually had them fail?

That is a loaded question, EVERYTHING has broken. If you are dependent on somthing working without fail the best method is K.I.S.S. (Keep It Simple Stupid) The more complicated something is, the more things there are to break. If your fancy auto hubs break in a snow storm in town... oh well. If they break in the kind of place we often find ourselves......

 

[thefirstzukman]

Manual hubs are stronger than a auto hub and more dependable also.

As for the chevy auto there is not a hub per say there is an accuator in the front axle that is must comonly refered to as "the donkey dick" on pre 97' trucks it has a high failure rate and a upgrade to the new 97' style. there is no vaccume on a chevy it is all electrical. The dodge and jeeps run on vaccume. on the chevy no 4wd is either a fuse, broken wire or a faulty donkey dick.

Good luck

 

[timpanogos]

The dodge and jeeps run on vaccume. on the chevy no 4wd is either a fuse, broken wire or a faulty donkey dick.

Maybe this is a way easy fix ... then again, would hate for a bad donkey dick

Where is the donkey dick physically located? How does one check it (with out getting it all excited of course)