Front end grinding when manual hubs unlocked

Hello fellow Taco owners, I'm looking for some advice. I've scoured the internet, and can't seem to find anything on my particular issue.

I have a 1996 Tacoma 4x4 with manual locking hubs, and this morning I noticed a grinding noise as I was driving around town (+-30MPH). I've been trying to isolate the noise, and can't seem to figure it out. It sounds like it's coming from the front left and right wheels. Doesn't make the noise when hubs are locked, or when hubs are unlocked and transfer case is in 4x4 mode. it only makes the noise when in 2x4 and hubs are free. I'm really at a loss.

at first I was thinking wheel bearings, but those are under load no matter what the drivetrain is doing, right? are my front hubs bad? I do know the PO left the front hubs locked most, if not all of the time. Maybe I hurt them when I unlocked them? they didn't seem too unreasonably stiff.

Any thoughts would be appreciated.

 

Hm, maybe the locking ring hasn't completely disengage..

 

that's what I'm thinking now that I've opened up the hubs. they stopped grinding after I took them apart, but once I locked and unlocked them they started grinding again. one of the hubs had metal shavings in it, so I cleaned it all out and applied fresh new grease. gonna to the same for the other one.

 

oh shit son...not good. hopefully the 4x4 masters in this forum come up in here.

 

New Revelation. I was taking a closer look at a teardown guide, and one of the clutch springs isn't seated into the clutch. I'm gonna go tear 'em apart again and see what's good.

 

okay, after some disassembly, It turns out the grinding is caused by the bearings holding the CV axle inside the locking hub. When I put a 12MM wrench on the center bolt and turn it manually, I have hear the grinding noise. any idea what these are called?

 

Probably ask at this site on parts. http://wabfab.3dcartstores.com/Aisin-Manual-Hubs_c_59.html

Or I'll be damn thats the actual wheel bearing that went nuts

 

It's not the actual wheel bearing because the wheel itself is tight, and just fine. the CV axle will jiggle inside of the hub when I yank on it, so whatever bearing that holds that in place is definitely the issue.

 

anyone know what that bearing is called? it's definitely bad, I just can't seem to find what part it actually is.

 

dude provide a picture..

 

not at home so I can't take a picture of the actual truck, but this is what I'm talking about. only difference is I didn't take the bolt out, and the bolt is completely tight. the CV axle wiggles inside the hub.

 

I watched this video and there doesn't seem to be a locking nut but there is suppose to be a c clip that holds the axle in place. I hope you have that.

https://www.youtube.com/watch?v=3HzgGFo_-9A

 

okay, here's what mine looks like. the entire assembly inside the locking hub wobbles a little, and when I turn the CV axle with a ratchet (wheel on the ground) it makes the grinding noise every once in a while.

 

I put everything back together as it's supposed to be and took it around the block. Grinding is still there, but much less. I'm all out of ideas without throwing parts at it. Is there a way to drive it without the locking hubs installed to see if they are the issue?

 

It sounds like the brass bushings that the CV rides on in the hub is going bad or is badly worn. I think there is a inner one and outer one ( I am not entirely sure). The reason the noise tends to go away when you lock it is because the cv is now supported and locked in position by the splines in the hub. When the hub is unlocked, the CV rotates and sits on this brash bushings.

You might be able to swap them out (but I think that you will have to press the portion of the hub that is pressed into the spindle/bearing needs to be pressed out). Again, not entirely sure. You'll have to completely disassemble the hub and pull the cv out to get access to see these bushings.

https://www.youtube.com/watch?v=HmyQCCbgW54

 

It's the hub needle bearings. Easy enough job. $12 part.

Just rent a blind hole puller from AutoZone. Pull the inside bronze bushing out. Be careful, they're not sold individually.

Pull the needle bearing. Replace. Tip: freeze the bearing and bushing in a freezer for a few hours and heat the hub mildlybwith a torch before tapping in with a socket and use a rubber mallet on the bushing.

After time the bronze bushings break down and ruin the bearing.

 

They're needle bearings and are known to seize when the outer seal fails, they rust to the CV shaft. I have one in my garage I'll take a pic of in a minute

 

Guess they're $15 now.

http://www.offroadsolutions.com/products/ors-replacement-inner-hub-bearing/

 

Thanks so much for the help guys! I’ll order the parts and get this taco back on the road!