4 runner hubs not engaging
 

Got a slight probem here, just had our first snowfall here in dayton ohio and noticed my 4wd is not working. I used to own an 89 pu with a v6 and manually locking hubs, the body was pretty rough and after numerous issues i bought a 91 runner without an engine and dropped m v6 in. the runner has ADD and it seems as if the hubs are not engagin when i put it in 4 wheel.

I really liked the fact i had manually locking hubs and was wondering what is all necessary to put my manually locking hubs in. Maybe just completely switch the axle assembly?

Any ideas would be well appreciated


Marcus

for the hubs https://www.yotatech.com/forums/f128/aisin-manual-hubs-2nd-gen-4runner-76353/ also sounds like there could be a vacuum leak somewhere

With ADD, there is no 'locking' or 'unlocking' of the hubs. There is a drive flange in place of the manual hub. The CVs have a solid connection to the wheel. It's the same as having your manual hubs locked in all the time. If the wheel is turning, the CV is turning with it. Always.

Your problem is probably vacuum related....Unless someone stole your front driveline. ;)

If you want to swap your ADD flanges out for your manual hubs. It is a simple as removing the ADD flange and bolting the manual hub in it's place. It's a direct bolt-on swap.

x2 on the vacuum problem.

Changing to manual hubs will NOT help the problem that you are having.

Check that all of your vacuum hoses are properly connected, an in good condition.

Thank you, do you know where i can get a good diagram of the vac lines? The one in the haynes is about worthless and I will be studying the eng compartment to look at what went wrong.

In your opinion, since i have a set of aisin manual hubs, would you swap those on instead of the add? I know you said it wouldn't fix the problem, but am i right to figure on seeing better mpg and maybe more reliability? thanks

Feel free to browse the reference pics from my 3.4 conversion project - they may help:

http://rides.webshots.com/album/555352913PvUzIT

You'll also find a Toyota Factory Service Manual helpful. I believe that one for a '93 has been posted on-line - just search.

As to the manual hubs -- all that it will really do for you is to save some wear and tear on your CV joints. You will still have your ADD differential, with the addition of the lock out hubs. For instance: if you install the manual hubs, you can free the hubs to reduce wear when you know that you will not need 4WD (be certain NOT to try to engage 4WD without locking the hubs, first). If, however, you know that you are going to need 4WD intermitantly (like the Denver metro snowstorms of the last few weeks), you can engage the hubs, and leave them engaged, shifting in and out of 4WD as you need (at the transfer case lever), since, functionally, the system is identical to the factory set up with the locking plate hubs (assuming the your ADD is functional).

Fuel milage savings with the hubs freed is insignificant, at best.