Free wheeling hubs?

If your assessment is perfect in every way and you want no advice then get the parts and do the mod and show us if your so confident in your book reading. The way things look in a book and the way things work in the real world are two different things. There would be the issue of if the computer detects something not right then nothing engages. Just because your engineering degree says you are an engineer doesn't mean you know everything about how modern vehicle systems work. This is 2012 not 1990 things have changed in how vehicles are fabricated.

 

Then leave. You wont be missed I promise

 

What you need is a little bit of ATRAC

 

Intersting thread... I hope the OP doesn't let the 'children' chase him off.

Blue, you are talking about adding a third differential if you want AWD (full time 4WD), correct? Or, are you just using the term AWD to mean something else? In winter snow covered roads, what is the problem with shifting into H4 now? If you want the security of high speed driving over patches of snow then no snow, and don't want to keep using the transfer case, you would be surprised how well VSC works in H2 at handling the sudden changes in road surfaces.

 

I see where you got this info, but it appears to be a typo on the toyota website - they appear to be using the 5 lug mpg numbers for the 4 banger access cab prerunner. The V6 numbers give a better picture.

 

Detour down mpgs lane discounted - the spline count size is the authoritative answer.

 

x1000!

 

No, your assessment isn't perfect. Much like your assessment of the time it takes to build a front bumper.

As bjmoose explained, the ADD is electronically controlled. If the module doesn't see the correct output from the diff you don't get 4x4. So you'll need to add a manual shift lever to your t-case. Your YJ is a vacuum operated system and much easer to defeat.

Not to mention, I'm pretty sure the CV shafts haven't different spline counts IIRC.

How exactly do you propose to get information on feasibility without advice and opinion?

 

Thank you, that was the kind of factual information I was looking for! Discouraging, but far from an actual problem.

I would think it would be a better starting point to modify CV shafts rather than getting into something that radical. 2nd gen is a wider truck than 1st, to the axles would need to be modified (lengthened) anyway.

 

First gen - Spline count for CV shaft is different than second gen.
First gen used a pressed-fit hub bearing that is pressed directly into the spindle.
Second gen has a hub bearing that is press-fit into a hub assembly, that is then BOLTED onto the spindle.
The hub itself differs on 1st gen once you reach 2001, where the hub itself changed to a non-selectable type.

In order to convert a second gen non-selectable to a 1st gen-style selectable, you would have to change the entire spindle assembly to include:
C/V shaft (may need custom shaft lengths)
spindle
hub
selector (the manual selector on the hub)

Problems that may cause an issue - I have no idea if the spindle assembly will be a bolt in replacement or not. I have done several bearing replacements for some of the guys on here, and I honestly never really looked to see if a conversion would be reasonably feasable or not.

 

So you are saying that aside from the spline count, there are other size differences as well? I would appreciate any pictures or measurements you can provide.

Also, I'm not sure what you are referring to as "LC spindles", do you have a link?

 

Yes, I did notice some difference in the way the bearings are arranged. Fortunately, bearings are fairly easy to deal with.

As for the hub parts, they show the same part numbers for 2000 and older as for 2001 and newer. From 1997 through 2000, there were two hubs available simultaneously for free running and ADD, the free running option was dropped in 2001.

Regarding the spindles... definitely not bolt in replacements. In response to the "wheels fall off" problems of the 1st gen, the lower ball joint was changed in a way where the LCA now sits on top of the spindle, rather than hanging down from it. In other words, the older style had the weight of the truck trying to pull the ball out of the cup, the newer has the weight of the truck puching the ball into the cup.

 

My parts catalog shows that the manual lockout hub is a different part number from the ADD. The manual hub has the bolt holes that the selector bolts into, and the shaft itself is splined to the selector. This is unlike the ADD where the hub is smooth with no bolt holes, and the shaft splines into the hub.
2000 and older models
4WD with auto-disconnect part number 43502-35170
4WD w/o auto-disconnect part number 43502-35160
2001 and newer
4WD with auto-disconnect part number 43502-35170

Note that the manual hub has a different part number.

Nice kit! Bet it was expensive as hell.

 

Most all of the manual hubs are weaker. They actually have what is called a mechanical "fuse" that is designed to break before enough torque can be applied that would break inner parts. This was actually a good thing. hubs are a lot cheaper in most cases than the CV shafts or inner gears of a front differential. I have ALWAYS converted my 4wd trucks to manual hubs, with the exception of my Jeep XJ. I didn't convert it because I just couldn't afford it at the time.

 

Exactly!!
The difference in the part number is manual vs automatic hubs, not year based. What that means is that you could bolt-on a 2000 manual hub to a 2001+. There was no redesign in 2001, only a reduction of options.

 

But you also have to take into account the bearings. The bearing part numbers between the manual and ADD systems is also different. This COULD mean that the inner shaft of the spindle has a different diameter as well as allowing a selector to bolt in. Otherwise why different part numbers for bearings as well?

 

I'm sure that a lot of the manual hub failures are related to how the 4wd is being used. Generally, the "wheeling" crowd will put a huge amount of strain on the front end parts that wouldnt be applied by the "snow" crowd, or other more typical "slippery use" cases. One of my plow trucks has *auto* locking hubs, and although they can be a bitch to convince to engage from time to time, I havent broken anything with those over 25 years.

 

I forgot to note that hubs are not "bolted" on. the hub itself is press-fitted into the bearing, and the bearing is press fitted into either the hub assembly(2nd gen) or the spindle assembly(1st gen)

What this means is that you would still have the problem of getting the bearings that go with the manual hub to work in the spindle/hub assembly of the second gen. The bearing part numbers are different in all 3 cases.