'93 4Runner 3.0 4WD with Warn Premium hubs

When the truck is in 2HI with the hubs locked, this awful sound comes from the front axle area. It's MUCH better in 4WD, but still there. Unfortunately, it's hard to describe the sound. It seems to be OK when you first start driving, then the sound will start (while still at a relatively low speed).

I thought it might be the hubs (and I kinda trashed one on the trail yesterday) so I took them off and put the ADD plates back on. Where the sound used to come from the passenger side, it now comes from both sides and louder.

Going to take it apart after work - need some input on what to look for. CV's? Wheel bearings? Is there a bushing or something in there that the CV spins inside of?

 

You need to jack it up and check it in 4wd.
I've seen something similiar - and best case, the trim ring around the front pinion would come loose and start turning in 4wd. It made horrible noises, but was relatively harmless.. Just hit it with a tac weld.

 

My uncles Ford had a bad bearing and it madea terrible honing noise.

 

Where the driveshaft attaches to the diff? Why would it make noise in 2WD then?

 

Just thought of something. The last couple times, it's been really slow to come out of 4WD...and isn't the passenger side the one that moves from the ADD?

 

No, the driver's side. You can get the bad noise in 2wd since with the hubs locked, the drive axles are spinning. ON the passenger side it's spinning all the way in to the diff, and on the driver's side, just to the ADD sleeve (if it's disconnected).

 

Let's start with simple things...is the front diff full of gear oil?

 

If you roll your car in neutral, does the rear driveshaft turn? :-)

IE, if you lock the hubs, you're going to turn that front driveshaft.

Don't worry.. your problem is something more signficant!

 

spindle bushings? my ADD truck makes horrible grinding noises and will until I press in a needle bearing!

 

I checked it a while ago, and it was good, and haven't seen any leak since then, so I assume there's oil in it (but you know what assuming does...).

The plan for tonight is to check all that kind of stuff. I will put it on jackstands and run it in 2WD and 4WD.

I guess that was my question - what all do I need to look at tonight to help narrow down the diagnosis so I can (hopefully) fix it tomorrow night?

 

You have dry spindle bushings. Need to lube them. I build a spindle lubricator for our shop, works great. To build your own spindle lubricator, you will need a spindle nut just like the 54mm one hoding the hub on. And you will need a 2" piece of water pipe about 4" long. Now you will need a dead cap for the end of the water pipe and a grease fitting in the dead cap. Braze or weld the nut to the end of the water pipe. Braze it air tight. Now remove your hub, and one spindle nut, and remove the snap ring and thrust washer from the end of the axle. Screw on your luber, load it with a grease gun until you see grease coming out from the back. Remove the lubricator, install the hardware, pull the axle back in and button it up!

 

So basically, I need to lube the "tunnel" that the CV axle goes through?

What kind of grease? Molydisulfide lithium?

 

Yes/Lithium

 

I don't think you are supposed to pump the whole space in the steering knuckle full of grease. If you were, Toyota would have made it easy for you to do it without having to make some tool yourself for the job. The FSM calls for greasing the bushings of the steering knuckle and the outer cv axle if you take it out and that should be enough.

 

OK, put it on jackstands, got the skidplate off and checked things out. The front diff was a little low - maybe 1/2 quart (might just be because the front was jacked up higher than the rear) - so I topped it off. The driver's side CV is leaking under the band on the inside, so I'll swap that out tonight. Couldn't see anything else - driveshaft looks good, no play in any of the u joints (but I'll grease it up tonight while I'm under there). Turned the wheels by hand and didn't hear anything.

 

I have a similar problem. With hubs locked in, and in either 2wd or 4wd, an OBVIOUS rubbing/grinding noise comes from front end. Doesn't happen all the time, will suddenly start making noise, continue for anywhere from 10 seconds to 1 minute, then stop for a while, then continue again. Started happening after I pulled apart pass. side hub. Replaced Aisin hubs with Warn ones after this noise started and still continues to this day.

 

it's your spindle bushings. replace them with needle bearings! there's a writeup in the tech section that has step by step instructions.

 

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edit: the moral of the story is don't leave your laptop on the floor where stupid cats can walk on it and post accidentially.

 

We are speaking of a 93, not the straight axle with trunions (85 and prior). Fill it up with grease!

 

Dont use the nmeedle bearings, just lube what ya have. Needle bearings will tear up the axle over time.