Barnski

Hello everyone!

I've recently bought a 1993 4Runner 3.0 V6 and ever since I bought it I have been looking at this forum for advice and generally found every answer I need without having to start a thread, so thanks everyone for all your help so far!

Anyway, I got the vehicle pretty cheaply knowing it had a few issues, and so far everything has been fairly simple to fix.

Since I bought it though, it has developed an intermittent grinding noise from the front right.
The noise is more persistent in the first few kms of driving, but once the car has warmed up disappears. It happens at any speed, and is mostly triggered by a bump. It will often stop on hitting a bump again, but I can kill it every time by hitting the brakes- obviously not ideal when I'm driving at 80km/h on a straight highway though... Sometimes switching to 4h will make the sound disappear, sometimes not. When it occurs, the passenger can feel the grinding at their feet.

On inspection of the side with problems I notice:
No play in ball joints
Wheel bearings seem smooth and play free
No sign of brakes rubbing
Split CV boots, both inboard and outboard

This led me to believe that it could be a problem with CV joints so I have decided to start with new boots. On taking the Cv axles out an inspecting them today, despite the split boots, they are fairly clean and well greased. the outboard joint has a little noticeable play but it does not seem like much. Should there be any play in this joint at all? The wheel bearing seems really really nice and smooth too.
The only thing I am left to disassemble is the hub. The noise can be heard and felt from the far right, so I am sure it is nothing to do with the diff.

Before dismantling the hub, I would like to know a little more about it. Unfortunately all the hubs pictured in my Haynes manual are very different to what I actually have, and I'm struggling to identify it with google as well.
They are pictured in this thread https://www.yotatech.com/forums/f116...dd-not-211312/
And also in chapter 9 p3 in the Haynes manual, diagram 2.3 shows an exploded view- but this is in context of the brake system and therefore does not explain anything. Judging by the way it goes together, I don't think its possible to disconnect the hub from the CV axle, so I'm guessing its the ADD system? Is it possible that something in here could be causing the grinding noise?

Thanks very much for any help!

Inu

Those are correct for your runner. Do you have the cv axle out? Mine had a retaining bolt behind the dust cover, the hub side stub shaft probly needs grease on the bushings( or bearings. Mines a 95 with bushings) stopped the noises on mine.

If your gonna remove the drive flange take care not to mushroom the studds getting the cone washers loose. I thread the nut just off the stubb and tap with a soft metal hammer.

j2the-e

I had a similar noise. It was my auto hubs hanging up. I swapped to manual hubs. Are you sure you have the ADD? You have vacuum lines going to the front diff? Take a picture of the front of the diff and one of the hub

Barnski

Thanks for the help with this. I think you must have been right about the source of the grinding Inu. I put on new boots and greased up the spindle and everything else that looked like it might want grease and now the noise has gone. Sweet!