Looking for a manual hub swap writeup

Please please forgive me if my search functions have failed me, but I am having trouble finding someone that’s done a good writeup on swapping out their ADD system and putting back in the good ol’ Aisin manual hubs. Does anyone have anything bookmarked that they can point me towards?

I’m wanting to do the manual hub swap with J-shifter and then hopefully follow it with a 5-speed swap into my ‘02 double cab TRD O/R.

Greatly appreciate any help!

 

https://www.tacomaworld.com/threads...or-the-1st-gen-tacoma-3rd-gen-4runner.460180/

 

https://youtu.be/1TpOYj0sUpA

https://youtu.be/TZ2sOfVrnhU

 

There's literally one on the first page of the forum right now

 

Appreciate your input.

Thanks boss man.

 

I considered the conversion way back when to improve gas mileage by freeing the front axle
The overall cost seemed to outweigh the savings from gas mileage.
With 200k I now wish I had done it.

 

Something to consider. The CV's in a manual hub set up are substantially weaker, and snap off road fairly easily. And can cause a lot of damage in replacement parts when they go exploding. Thought I'd throw it out there.

 

Is this fact or your opinion? I've rebooted both ADD axles and Manual hub axles and there's no difference in the size of the shafts that I remember. The main difference is how the CV interfaces with the hub. The ADD axles are locked in place into the hub with the large 35mm nut which also works to preload the bearing. With the Manual Hub CVs, the shaft slides into the hub and is held in place with a snap ring and back-up bolt.

I've never heard that manual hub CV axles are weaker than ADD CV axles. Care to elaborate where the weakness is with the Manual Hub axles and take it one step further by throwing out some further facts and information to back up your claim. I've been running manual hubs on my 3rd Gen 4runner for around a year now and have done several wheeling trips with no issues.

 

So, who’s got some parts for a manual hub conversion just sitting around that they want to unload?!?!?

 

That's pure internet mechanic hearsay. Tacoma CV axles, whether for manual hubs or ADD, are both 28 mm thick. For comparison, Dana 44 axle shafts are 30 mm thick. Driving habits more than anything else will affect how long your CV axles live. But with manual hubs you're not putting any wear on your CV axles the 90% of the time you're not in 4WD.

If you break an outer CV axle, the potential for damage is the same with either system. But if you break an inner CV axle you're much better off with manual hubs. You can unlock the hubs so the CV's won't spin and continue driving in 2WD. With ADD the CV axle is splined to the front wheel bearing and locked in place with a 35 mm nut. It's a do-able trail repair to partially disassemble the front suspension and yank the broken CV axle out, but it's a lot easier to just turn a dial.

 

Negative. The birfield shafts are nearly 1/4 thinner on a manual hub cv vs an ADD birf. And that's the place they shatter. Not the axle shafts. They're identical.

 

I've converted three pairs of ADD axles to manual hub axles and the only difference is the birf.

@Dirty Pool , can you set these guys straight?

 

Absolutely Sir, I'll take your light work.
Thought you would never ask.

The "main shaft" is indeed 28mm and is the same part between ADD and Man hubs with the exception of some 4Runners.
Comparison of (OE) Taco and at least some T4R shafts (necked down).




The man hub deficiency and reduced diameter as mentioned, is the stub shaft living in the man hub. When it goes it can take the hub/hub parts with it. No turn the dial and go home.

Specs from the late Cretaceous. Man hub around 20% thinner.
Further searches on the older forums will come up the same.
Give it time to load. How common is this? I would say when a man hub CV fails it's about a 50/50 chance it will be in the hub. Of course that's among folks that are proficient at breaking CVs.
Few pics from deep in the Dirty Pool.










Just for equal time this one broke at/in the diff. Of course it was an aftermarket "new" shaft (China)


This would not be fun on the trail or at home in the shop for that matter.

 

^Ah one of those looks familiar.

 

@License2Ill
Did you ever source new birfs?

 

Yes. ORS, the original supplier of the 1st gen ADD to manual hub kit offered to to sell me birfs and shafts but were out of stock upon my inquiry.

I bought a few off @Sideline Hero, who uses the 1st Gen manual hub birfields in his 2nd gen manual hub conversion kits. Which I'm very happy with. He works/worked for a Toyota parts Dept. And uses all OEM Toyota parts...

And I bought a few broken manual CV's to scavenge the birfs, which was a poor choice.

 

Well, I’ll admit when I’m wrong but I don’t think manual hubs are ticking time bombs. CV axle failures are pretty rare if they’re OEM. Lower ball joints are another story, though...

 

I agree with you. Even though there's some proof that the manual hub CV axle birfield shafts are thinner than the ADD shafts, I don't know if this qualifies @License2Ill statement that they are "Substantially Weaker". When I hear a statement like that, it sounds like if you hit a pebble in the trail your CV shafts are going to snap. However, knowing that a birfield shaft failure could cause damage to the free wheel hub, I carry an extra Aisin Free Wheel Hub with me along with a spare CV shaft when I'm wheeling.

I really like the benefits of this mod and wouldn't let the worry of a CV axle failure sway me to not do it.

 

Substantially weaker is semi-close to an opinion. I snapped three oem manual CV's and not a single ADD. None of the roads where breakage occurred were especially difficult. So that's enough for me to be up my own ass and call them substantially weaker.

If I knew I'd be through this many CV's before I converted to manual hubs I might have made a different decision.

I converted six years ago before it was a popular thing to do. And before all the info that's out now making it popular. I'm adding to the conversation for people thinking about doing the mod to make an informed decision
the fact being the manual hub CVs are thinner and therefore weaker.

But on the plus side.

I get 3/10ths better mpg with the hubs unlocked. Free 2 LO. Oh and if I snap a CV in the hub like they seem to like to do, I can just drive home unlike ADD trucks where the birf stub holds the bearings together.

 

If you're going through the troubles of carrying a spare CV and hub dial, you're going to want to carry both inner and outer bronze bushings, the hub needle bearing and a blind-hole puller to pull those damaged parts out of your hub. Because when the birf stub goes all those parts probably will go with it.