Phessor

I was asked by my neighbor if I could replace his front wheel bearings on his 1988 4Runner and it has automatic locking hubs.
I have never worked on them, does anyone have an exploded view of them?
And before any wise acres start in, YES I have looked for this information.
Any help would be greatly appreciated.
Thank you.

Terrys87

iTrader: (1)

This is for a 93 but would assume the hubs would be the same.
http://www.ether3al.com/93fsm-mobile...onandaxle.html

I was sure that it would be in there but am having trouble finding it myself.

RJR

I'm not sure Toyota used auto hubs in '93 anymore. By then I think they went to the ADD system. The auto hubs were a bad idea whose time really never came. I had them on my '84 Suburban and they were more complicated than a swiss watch. Clever mechanical mechanism, but a lot to go wrong.

I'm guessing you would need to find a manual for an '88-'90 vehicle, which I haven't seen on the internet. Might try googling "Toyota auto hubs" and see what you come up with.

wyoming9

iTrader: (1)

About the best thing you could do is swap them over to regular locking hubs

Now my old Haynes Manual for the 79 to 95 years had a break down for them.

I am sure the Factory Service Manual has them as well.

The way they keep changing things who knows if it will be in the newer editions

When I removed mine I knew they were not going back on.

Like any other Toyota Hubs you still have the dreaded cone washers to fight with.

Gevo

I second spending the $50-75 bucks on some used manual hubs. Easy install, easy maintenance.... not much to go wrong.

Phessor

I was able to figure them out, thank you.
I have an extra set of manual locking hubs I tried talking my neighbor into, but he likes his automatic locking hubs.

RJR

As long as the auto hubs are working, and you keep water and dirt out, they are convenient. Just not quite as fool-proof as the manual ones.

wyoming9

iTrader: (1)

As long as you never really need to use them once your already stuck!!

RJR

There's a popular misconception that the vehicle has to be moving in order for auto hubs to lock up. That's not true, at least for the ones in my Suburban. What is required is that the drive axle rotate about 1/4 turn in the direction of travel. This happens as soon as you engage 4wd and let out the clutch, regardless of whether or not the vehicle will move. It's the rotation of the drive axle with respect to the fixed spindle that drives the hub into lock, and has nothing to do with the actual wheel turning. It also works in both forward and reverse, although if you're rocking the vehicle, the hub tends to go from forward lock through unlock and into reverse lock, etc., etc.

Like I said, it's a clever mechanical mechanism, just overly complicated and a bit fragile for what it does and the conditions in which it has to work. The ADD is a much better and more rugged solution for on-the-fly 4wd engagement.

wyoming9

iTrader: (1)

Having had them fail to lock once was enough


I would guess the GM ones may have worked different.

The down side is without crawling under neath there was no way to tell if the unlocked

millball

Had some Warn made automatics on one of my IH Scouts.

Factory installation with IH markings on the selector dial.

Those could be manually locked as well as the automatic feature.

As I recall, the auto system cammed up some rollers tight to lock and the manual locking used a splined slug, like most manual hubs do.

They were in poor shape when I got the truck so I changed them out pretty quick for straight manual ones.

I am pretty sure my '87 Runner came with auto hubs, but they were long gone when I got it; changed out for Warns.

Never seen the Aisin automatics, do they have the choice to manually lock as well???

RJR

The GM ones used a sprague clutch-like affair to drive a cam that forced the splines into lockup. Once they were locked, they were just as strong as manual, because the drive mechanism was identical. I never had much trouble with them, but I didn't wheel that hard with the Suburban. Plus, everything else on that truck failed before the hubs had a chance. 100,000 miles included one new engine, a rebuilt transmission, a complete repaint, a couple rebuilt drive shafts, new brake rotors, new radiator, two power steering pumps, and numerous door and window mechanism repairs. 1980's GM quality at its finest.