should I avoid auto locking hubs? reasons please. (1 Viewer)

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pretty much what the title says. I've looked at some trucks that have the auto locking hubs but i'm not too keen on them. Please give me input, experiences, etc.
 
I have not owned a truck with manual hubs, but do have friend that have them. They are definitely more reliable. Other than that, I prefer ADD, because I hate getting out of the truck when caught in a snow storm. My truck is going on 104k miles with no problems. My old 4Runner had 130k with no problems. My friend has ~200k with no problems. Not saying that they are bullet-proof, because they have gone out on some trucks, but they are still reliable IMO.

Now, it also does depend on what kind of a vehicle this is going on. A daily driver, I'd stick with auto. Trail only rig, manual. Little of both---your call.
 
It depends on how you are going to use your truck.

If it's a D/D, with some offroad use, AND you're not going to do a suspension lift of over 2", then stay with auto hubs. They are definately more convienent than manuals in inclimate weather, and probably more reliable too (ever tried to lock in frozen manual hubs?).

If you're going to need more than 2" of suspension lift, or if you're going to offroad hard enough to be breaking CV joints, then manual hubs are the way to go.

If you lift more than 2", then the CV angles will be greater, resulting in the fins of the boots rubbing and premature wear of the boots/cv joints because they are always turning. This is not an issue with manual hubs, because the only time that the cvs are turning is when 4 wheel drive is engaged, and that is usually at low speed anyway.

Also, auto hub spindles are semi floating, so if you break a CV then you have to change it on the spot. You cannot leave it in, because the shafts will go flailing around and tear more stuff up because the hubs are always locked. You also cannot remove the CV and drive it, because the spindles are semi-floating, and the stub shaft is what holds it together. With manual hubs, you can unlock the hubs and drive home. You can also remove the entire CV shaft if you have to, and the spindles will stay together because they are full floating.

Now....I know that someone will say that the shafts on manual hub CVs are thinner, and more likely to break than those on auto hub CVs. Yes, they ARE slightly thinner, but the weak link in a CV driveline isn't the shaft, but the outer tulip joint. Just as with birfield axles, 98% of breakages will occur when the wheels are turned, and excessive amounts of skinny pedal are applied. I have only seen a couple of broken shafts, and those were in locked front ends, but I've seen (and broken) many outer joints.

When I did my manual hub conversion I purposly tried to see if I could break a shaft, and the cage of the outer tulip joint grenaded long before the shaft would have failed (of course I'm open too).

Just my :2cents:
 
does the hubs being locked all the time with auto locking cut down on mpg's? and can you shift into 4wd on the fly?
 
It's a pretty costly job. I believe around $1000 or more? The manual hubs really won't affect your MPG's. And are you asking if you can shift on the fly with ADD or manual? With ADD, yes, but manual, no. You have to literally get out of the truck to lock the hubs.
 
I've looked at some trucks that have the auto locking hubs but i'm not too keen on them. Please give me input, experiences, etc.

First there’s some misinformation that needs to be cleared up regarding strength, terms, amount of lift etc:

Several years ago Downey did an informal, long-term study on boot wear comparing lifted and non lifted ADD trucks. After having some lifted rigs go 100k with no boot issues and some stock rigs with a quarter of the mileage blowing boots their conclusion: it's a crap-shoot.

When lifting the front, it’s not the fins rubbing that becomes the issue, it’s the amount of lift that pulls on the boot attachment at the axle shaft, resulting in the grease loss. Once the joint/tulip is out of grease is when the problem occurs. I’ve ran well over 2” for over 70K with rubbing fins, but the grease is pushed out the inner end of the outer boot, not the fins.

Technically, they are not ADD hubs. They are actually just drive flanges, as there is nothing to automatically lock or unlock. ADD refers to the front differential.

The ADD system, or front axle shafts (called CVs) on the tacomas, 4runner, tundras, etc. are NOT semi-floating axles, they are FULL FLOATING. In a full-floater system, the axle shaft only serves to transmit the rotational torque from the differential out to the wheel. It does not carry the weight of the vehicle like a semi-floater (rear axle on our trucks) does. Exampe; on a full floater, a spindle is attached to the outer end of the axle housing. The hub's cap is attached to this spindle and rides on tapered roller bearings. It is this assembly that carries the vehicle weight. As such, a full-floating axle system is considerably stronger than an equivalently sized semi-floating system. This is how ORS sells the full floater conversion for Tacoma, and makes rear disk possible.

The fact that the outer stub holds the wheel bearing in place has no bearing (ha ha) on the weight of the vehicle or how it is supported, which is the defining characteristic of the full-floater vs the semi-floater. It can be hypothesized that any 4wd setup that has the front axle steering is a full floating axle by default. IFS is also full floating.

So the CVs on ADDs rotate/spin with the wheel assembly, and are always turning when the vehicle is in motion at the same speed as the wheel it’s attached to. Because of this, if you break a CV, then the axle shaft spins wildly striking things in the vicinity (lower control arms, coil, shock, etc) making a hell of a racket. However, at low speeds, you CAN drive on it to get to a nice level shady spot to swap it out (which in fact is easier than swapping out the CVs on the manual hubs).

It is true that on the ADD assembly you can NOT run without the axle shaft (CV). But no one ever explains this. It’s because the outerstub of the CV (the one closest to the wheel) is required to keep the bearings seated on the front wheel/spindle assembly. There is nothing to support or retain the wheel bearing when the outer CV is not there. The CV axle slides thru the inside of the wheel bearing and is retained with a large nut (35mm-36mm). Remove it and the wheel bearing has nothing to retain it in its housing (knuckle).
You can not drive your truck without at least the outer part of the CV installed!


Now, if you were in a real crunch with a broken CV, you can either disassemble the outer CV joint (huge pain in the ass on the trail) and leave the outer casing/stub shaft in or just cut the axle shaft. The ADD models have to have the CV axles installed and the nut torqued properly or the wheel bearing will grenade. The outer knuckle and big giant 35 mm nut are what hold every thing together, and without the axle, there’s nothing for the 35mm nut to fasten to. Go back in the archives of TTORA and this has been done by several people (because none were available, they were already ruined, had more money than sense, but the point is, it is possible). But then it’s no good for a core unless you use some super glue.:D

So that brings us to strength;

starting from the hub side the diameter of the shafts are:
manual 27.22mm
ADD 33.35mm, so 6.13mm larger

main axle shaft:
manual 28.80mm
ADD 28.85mm, so only .05mm larger and they are the same size entering the front diff into the spider gears.


Stock components compared to stock components, manual axles will never be as strong as ADD, nor will it ever be cheaper to repair (every priced the aisin hubs?), nor will it ever be as easy to repair. But the strength of the ADD CVs is probably ultimately negligible over the manuals.


Anyone doing a manual hub conversion will note that the outer axle stub used in manual hubs trucks simply appears weaker than ADD axles. This is because it's a little smaller in OD and because of the groove for the C clip.

Now, doing a manual hub swap is completely senseless, UNLESS you have a donor truck with manual hubs, or money burning a hole in your pocket. Since the ADD axles don’t technically have hubs, you can’t just slap on some lock outs and be done. You need manual hubs, spindles, probably new bearings pressed in the spindles (good luck), manual CVs, and other crap. You can buy the fancy setup that Downey or ORS sells. It’s only $1K or more!
Off Road Solutions - Products - Tacomas - Drivetrain

But why? There will be no difference in mpg (it’s been documented), no increase in strength, no ease of changing them out when the break, and no increase in the size of your gnads. The only benefit is the idea that you can unlock the hub (if you break one) to drive home. But I’m sorry, if you’re not carrying at least one spare, just stay off the trails. They can be changed out in under 30 minutes.

I’m only trying to provide the “most accurate” info. If I’ve hurt anyones’ feelers, I apologize, I just know I hate searching to only come across inaccurate info and opinions.
 
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does the hubs being locked all the time with auto locking cut down on mpg's? and can you shift into 4wd on the fly?

No to the first, but why? I only did that if circumstances deemed 4wd was going to be required.

Read the owner's manual to the second. But you should be able to if the hubs are locked, within reason. I always prefered to slow down rather than slam it into 4wd at highway speeds. I still slow (a little) even though my owners manual says I can.
 
My feelers certainly aren't hurt, its better to have accurate information. I've always been told that the front spindles of ADD trucks are semi-floating, and thats why you can't run without the CVs in place.

Also, as you said, CV wear and boot wear are a crap shoot. Its MUCH debated on many offroad sites such as TTORA, but every truck is different, and everyones driving is different.

I agree, that changing from ADD to manual hubs would be a waste of money if you had to pay for the ORS or Downey kit.

I changed mine for 4 reasons:

1. I had another Tacoma that I'm SASing, so all the parts were free.

2. The donor truck had 4.10 gears, so it got me out of my 3.58s, again for free.

3. I've broken lots of CVs, and several of them were in places where there was no level, or dry (much less shady) place to change them safetly. In order to have a safe place to jack up the truck, I would have had to be strapped quite a way, through tight trails to flat, dry ground, risking damage to my truck, and the truck pulling me.

4. Just to get experience with something different....both driving with it, and working on it.

Oh....5 reasons...it gave me bigger nuts.....because I about burst my sack trying to lock my manual hubs after getting 20" of snow and they were totally froze up. :doh:

What it boils down to is preference and convience.

ADD is far more convienent.

I believe that ADD is just as reliable, if not more so (at least on the trucks that have vacum operated disconnects......I dont care for the electrically operated ones...again, my opinion).
 
First there’s some misinformation that needs to be cleared up regarding strength, terms, amount of lift etc:

It is true that on the ADD assembly you can NOT run without the axle shaft (CV). But no one ever explains this. It’s because the outerstub of the CV (the one closest to the wheel) is required to keep the bearings seated on the front wheel/spindle assembly. There is nothing to support or retain the wheel bearing when the outer CV is not there. The CV axle slides thru the inside of the wheel bearing and is retained with a large nut (35mm-36mm). Remove it and the wheel bearing has nothing to retain it in its housing (knuckle).
You can not drive your truck without at least the outer part of the CV installed!


I’m only trying to provide the “most accurate” info. If I’ve hurt anyones’ feelers, I apologize, I just know I hate searching to only come across inaccurate info and opinions.

Dang my first post and it has to be about axles....hehe

Oh well this is what I get when I said I'd join this board.

FlatlandTRD, I pretty much agree with everything you wrote except for the above statement.

To explain, The bearing assembly is press fit to the hub and spindle, this takes anywhere between 15 and 30 tons of force to take apart. Technically the axle stub holds it together, but actually only holds the seal in place to keep dirt out. Not running the axle won't cause bearing failure or them to slip off.

Now has anyone ran without and axle, yes plenty have, but they have also destroyed the bearings because they failed to cover the hole and prevent dirt from entering. I've yet to see a case where the bearing slipped off the shaft. Could it possibly happen, you bet, if you can put at least 15 tons of lateral force on it driving.

If you break and axle and don't have a spare you can run without it, but you must seal the hole to prevent dirt from entering. The simple way to do this is to use the plastic lid off a Pringles chip can, they fit perfectly inside the mating seal on the spindle or use some duct tape. I have done this and driven nearly 90 miles without any problems. Same with others that I know who were in similar situation.

Now would I drive around daily without axles? most likely not, but if it gets me off the trail and home you bet.
 
First there’s some misinformation that needs to be cleared up regarding strength, terms, amount of lift etc:

It is true that on the ADD assembly you can NOT run without the axle shaft (CV). But no one ever explains this. It’s because the outerstub of the CV (the one closest to the wheel) is required to keep the bearings seated on the front wheel/spindle assembly. There is nothing to support or retain the wheel bearing when the outer CV is not there. The CV axle slides thru the inside of the wheel bearing and is retained with a large nut (35mm-36mm). Remove it and the wheel bearing has nothing to retain it in its housing (knuckle).
You can not drive your truck without at least the outer part of the CV installed!


I’m only trying to provide the “most accurate” info. If I’ve hurt anyones’ feelers, I apologize, I just know I hate searching to only come across inaccurate info and opinions.

Dang my first post and it has to be about axles....hehe

Oh well this is what I get when I said I'd join this board.

FlatlandTRD, I pretty much agree with everything you wrote except for the above statement.

To explain, The bearing assembly is press fit to the hub and spindle, this takes anywhere between 15 and 30 tons of force to take apart. Technically the axle stub holds it together, but actually only holds the seal in place to keep dirt out. Not running the axle won't cause bearing failure or them to slip off.

Now has anyone ran without and axle, yes plenty have, but they have also destroyed the bearings because they failed to cover the hole and prevent dirt from entering. I've yet to see a case where the bearing slipped off the shaft. Could it possibly happen, you bet, if you can put at least 15 tons of lateral force on it driving.

If you break and axle and don't have a spare you can run without it, but you must seal the hole to prevent dirt from entering. The simple way to do this is to use the plastic lid off a Pringles chip can, they fit perfectly inside the mating seal on the spindle or use some duct tape. I have done this and driven nearly 90 miles without any problems. Same with others that I know who were in similar situation.

Now would I drive around daily without axles? most likely not, but if it gets me off the trail and home you bet.
 
Spare what?

differential.

But I’m sorry, if you’re not carrying at least one spare, just stay off the trails. They can be changed out in under 30 minutes.

Spare what? auto hub, CV joint? what part would brake that a spare can fix in 30 minutes? Sorry for the stupid ?

Jay
 
This thread brings the funny!

I prefer ADD, because I hate getting out of the truck when caught in a snow storm.


Thats just vaginal :lol:, how fast you drive in a snow storm is no concern of mine but I usually dont go fast enough to warrant un locking the hubs. Just prior and during, I would lock them and use H2 on the hard stuff, if it were me ;p .....shift on the fly!


:lol:

Oh....5 reasons...it gave me bigger nuts.....because I about burst my sack trying to lock my manual hubs after getting 20" of snow and they were totally froze up. :doh:

What it boils down to is preference and convience.

ADD is far more convienent.


and thats just dang funny!



Me, I like Low2 (and not binding in Low2 on a hard surface) and not having all that stuff spinning, that is called "drag" and in my oh so humble opinion I believe that any gasoline powered vehicle, especially ones with smaller power plants can pick up on this easily and however small it might be I do not care for it and its overall added consumption and wear.

But thats just how I am, I was raised "if you want 4WD" you got yer az out and turned a hub!


"you can have my manual hubs!, when you pry them from my cold, dead fingers."


:flipoff2:
 
I thought one of the advantages of manual hubs, whether converting a 3rd Gen 4Runner or older truck was that should an axle break all you would have to do would be to unlock the hub with the broken axle and continue along the trail in 3WD. Pull and repair the broken axle at home or camp.

Am I misinformed, missing something or just completely confused? Thanks.

But why? There will be no difference in mpg (it’s been documented), no increase in strength, * * * no ease of changing them out when the break, * * * and no increase in the size of your gnads. The only benefit is the idea that you can unlock the hub (if you break one) to drive home. But I’m sorry, if you’re not carrying at least one spare, just stay off the trails. They can be changed out in under 30 minutes.
 
I thought one of the advantages of manual hubs, whether converting a 3rd Gen 4Runner or older truck was that should an axle break all you would have to do would be to unlock the hub with the broken axle and continue along the trail in 3WD. Pull and repair the broken axle at home or camp.

Am I misinformed, missing something or just completely confused? Thanks.


oh hell yeah!

If your fronts open all your doing is waisting time cuz all the torque would just go the **Axle** with the LEAST amount of resistance on it.

:confused:
 
differential.

But I’m sorry, if you’re not carrying at least one spare, just stay off the trails. They can be changed out in under 30 minutes.


Spare what? auto hub, CV joint? what part would brake that a spare can fix in 30 minutes? Sorry for the stupid ?

Jay

The ADD CV axles can easily be swapped out in under 30 minutes and usually takes me 15 minutes when I bust one...


I thought one of the advantages of manual hubs, whether converting a 3rd Gen 4Runner or older truck was that should an axle break all you would have to do would be to unlock the hub with the broken axle and continue along the trail in 3WD. Pull and repair the broken axle at home or camp.



Am I misinformed, missing something or just completely confused? Thanks.

There really isn't much advantage with manual hubs, considering just how fast you can swap out a broken axle. The only advantage I can think of is if your running an ARB air locker, then unlocking the hub will stop the diff from spinning saving wear and tear on the "o"-rings. There really isn't any difference in fuel mileage......
 
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Oh well this is what I get when I said I'd join this board.

To explain, The bearing assembly is press fit to the hub and spindle, this takes anywhere between 15 and 30 tons of force to take apart. Technically the axle stub holds it together, but actually only holds the seal in place to keep dirt out. Not running the axle won't cause bearing failure or them to slip off.

First, welcome, although you've been around longer than most of us (remember the Delphi days). Second, thanks for the clarification, I was trying to keep it simple without bringing the press into it. Although I remember talk about the bearing loosening over time, could have been due to debri or no seal. Actually never heard of anyone without at least the outer stub. Good to know on the Pringles lid :D

I know it'd be a lot, but maybe if you did a write up on yours, or at least linked it. Maybe open up some minds to other possibilities other than SAS in order to wheel.
 
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Although I remember talk about the bearing loosening over time, could have been due to debri or no seal. Actually never heard of anyone without at least the outer stub.

Damnit Bruce, now you got me quoting myself. So I'm going to have to retract some. I will not/would not advise running without at least the outer stub (unless it's an emergency). Why? Because of the full floater design and that the bearing is taking the load. There needs to be something there to support the bearing.

The logic? Look at the prerunner, same design as the 4wd minus the front axle shafts. So what's the difference? The prerunner requires a lock nut (torqued to 203 ft lbs) on the inside of the spindle to support the bearing, then a grease cap. So if the Toyota engineers think there needs to be something there, I'll go with that.

I have not, and will not run without at least the outer stub. Unless I absolutely have to, but I always carry at least two axle shafts so I don't see that happening. Irregardless of the amount of torque required to press the bearings in the spindle (actually "steering knuckle" to be technically correct).
 
Thats just vaginal :lol:, how fast you drive in a snow storm is no concern of mine but I usually dont go fast enough to warrant un locking the hubs. Just prior and during, I would lock them and use H2 on the hard stuff, if it were me ;p .....shift on the fly

:flipoff2:
Well, I don't know how much snow you get where you're at, but we got pounded pretty good here this year. There were times on the freeway and going up the mountain when we got hammered. The freeway was dangerous enough just trying pulling over (and not getting stuck! :D), but with the idiots on bald tires cruising the highway, it would not be the most comfortable feeling standing out there with cars sliding all around you. Then, you got the mountain roads, where at the base, it can be sunny, but as you start going up, snow starts to fall and you find yourself in the middle of a blizzard-like condition. There aren't hardly any places to pull over, either. Not fun.

I am good with giving the ol' J-shifter a tug and going on my way. :hillbilly:
 
LOL, got you quoting yourself.......

Reguardless if the axle stub is installed or not the bearing is still taking the same loading. Next time I press apart a hub assy, I'll post pictures on the wheel bearing assy and you'll see what I mean.

On my rig I only tighten them to around 60 ft lbs, well below recommended specs, yet I have never needed to replace my wheel bearings. I have re-packed them several times(a little trick of mine), but I won't go into details in this thread.

I never re-torque the 35mm nut to specs. Why? because it would be an absolute PITA to swap an axle in the field. To break one free it takes a large breaker bar and I usually add a 6' cheater to that, if it has never been apart before.


I've already said that I wouldn't drive around daily without the stub(something about just having it pressed on still bugs me), but I seriously doubt you'll ever lose a wheel doing it. But you can in a emergency drive without one, the stub axle or CV axle is just a failsafe if the bearing did fail the wheel won't come flying off.
 

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