4WD not working, 1st gen manual hubs

Hello Tacoma World! This is my first post, but I've been lurking for a while. If this post is in the wrong section please redirect me.
Last month the 4WD stopped working, i.e. I lock hubs and engage transfer case but no power to front wheels.
I don't think it's the transfer case because if I crawl along in 4lo and hang out the door to look under the truck (haha), the front drive shaft is still spinning. So is it the hubs? the axle? How do I diagnose it?

 

I'm assuming the DS does not spin, while in 2wd.
Hopefully, its just a bad hub. If either hub does not engage, then due to the open differential, 4WD won't work at all (no pulling with front tires)

If it were my truck, I'd diagnose a bad hub this way:
- park on level ground, parking brake engaged
- leave tranny in park (if AT), or in 1st gear (if manual)
- block the rear wheels
- put the TC in 4wd-hi
- jack up one front corner
- turn the lifted wheel (hub in free wheel)
- attempt to spin the wheel (wheel should spin freely)
- put hub into 'LOCK' position
- attempt to spin the wheel (wheel should NOT spin freely, if it does, then the hub is not engaging)

Repeat with other side.

 

Very good recommendations for testing there! ^^^^^^

A good simple test also would also be to lift the front wheels off the ground, securing the truck with jack stands, and engage both manual hubs. Have a friend hold the front drive shaft in place, and turn either front wheels. If the hubs are in good shape then the opposite wheel should turn in the opposite direction, and some resistance should be felt by the person holding the drive shaft. If the wheel spins freely, and there is NO resistance on the drive shaft, and no turning of the opposing wheel, then you have a probable hub problem. If you DO feel resistance in the drive shaft, but the opposing wheel does not spin, then THAT hub may be suspect.

 

My 89 had a vacuum solenoid on the passenger side fender that actuated the front diff. I believe these are the same. Mine crapped out and I had no 4wd. I bypassed it and had 4wd again. I would bet that to be your problem.
Why there are locking hubs, a manual xfer case and a vacuum actuator is beyond me.

 

Maybe yours was converted to manual and all the vacuums was left intact. That's what I did to my 93 4runner. Converted when vacuum actuator failed. Otherwise I don't think the manual hubs should also have an actuator, but I could be wrong.

The manual hubs on OP's truck could also be gunked up with grease and it's not engaging.

 

Thats very possible. It had warn hubs on it when I got it. But even with the hubs locked, when that actuator crapped out, I didnt have 4wd.

 

The 1st gen Tacoma trucks were all direct drive with no vacuum actuators for the front axle. Once the shifter was engaged on the TC, and the hubs were locked in, you were golden. No need for vacuum.

 

well...for manual hubs...

ADD has vacuum operated actuators for the front diff drive tube on the passenger side unless it is a push button 4wd system then its an electronic tube.

 

Thanks for all the replies! I used tan4x4's method and discovered that both the front hubs are not engaging. This is probably my fault; a few months ago I had the right hub of because... well, it's a long story that involves offroading, a lower BJ failure and a wheel rolling beside my truck haha. After a new LBJ, tie rod end, brake line, and alignment, the truck is back on the road. Anyways, while I had the right hub off I found that it was super gunky. So, I removed the left hub intending to clean it because I thought it would be dirty like the right one. But it was extremely clean.
I must have resembled them incorrectly. Is there a thread about the right way to instal hubs? Do I need to buy new ones? Thanks again!

 

No need to buy new ones.

http://www.4x4wire.com/toyota/maintenance/front_end/hub_rebuild/

 

Silas would be a good guy to ask about them as he has rebuilt a couple pairs. His screen name is Slodgetto. Here is his build: http://www.tacomaworld.com/forum/1s...gettos-green-dragon-4x4-conversion-build.html

Or TheRealSubba would be a good one to contact.



Edit: nevermind speak of the devil..

 

Lol gotta love the timing.
Yeah. I've been in and out of the aisin hubs numerous times.
I could probably rebuild one with my eyes close.

They're simple creatures, you just have to make sure they're put together properly.

 

Easier said, than done. Helps to have a properly working one in your hand so you can see how it is supposed to go together. It took me some trial and error to figure it out (many years ago).

This video might help even though the hub is from an old solid axle:
http://www.youtube.com/watch?v=-jd4KjXI5VU

 

Update: after taking the ASIN's off and looking at them/the way they work, I'm almost positive I put them back on correctly. I'm also positive I found the real problem haha...

Would the right terminology here be, "the axle is disconnected from the hub."?
This is surely my fault b/c this is the side that had the LBJ failure, and therefore the semi-rebuild.
What did I do wrong? How do I fix it?

Thanks again!

 

There should be a snap ring that goes over the axle that holds it into the hub. There should also be an 8mm bolt that threads into the very outside end of the CV, with a large washer, that is an extra fail-safe for that snap ring.
Head to the dealer and pick up those parts.

 

One day I locked hubs in and 4 wheel drive didn't work. I pulled the outside off to look and the bolt and washer were rolling around inside. Had to buy new bolt and washer. Fixed!! One of those good days.

 

Ok, I've run into a small problem that I can't find the solution to. I can't seem to get the axle end into the hub far enough, by a couple millimeters. I can fit the snap ring into the groove, but there's not enough room for the splined washer to fit behind it. I've read every step by step guide to cv axle/bearing replacement, but this issue is never mentioned in them.
Thanks for any help!

 

Have the CV axles been replaced? If so, its possible that the wrong axles may have been used. The ABS axle assemblies are slightly different from the non-ABS axles.

 

No, it's the original cv axle.
I tried making it work with the LBJ on and off. I'm still just a hair short of having enough room for the washer and the snap ring.