Heres the deal folks, I have had this very annoying issue for the last couple days. On tuesday I had some extra time on my hands so I lubed my drivetrain, front IFS, 4 points, 2 on the front driveline and 2 on the rear. Initially I had about 30 trouble free miles, but after that there has been an annoying and quite loud chirp somewhere under the vehicle, it is directly related to wheel speed and temperature, cold truck=no noise, the longer it runs the louder the noise gets.

other pertinent information
-it is a 94 SR5 4runner, 3vze
-tore the rear driveline off today, replaced one u-joint, the other had zero play and felt good.
-brakes are new as off july on all 4 wheels
-rear axle was rebuilt in april
-both cv boots are torn, but plenty of grease is still on the joints

Any help would be greatly appreciated!

*UPDATE* 12/31
-Both CV's replaced
-front wheel bearings looks good and were just repacked
-both rear driveline u-joints replaced
-noise is constant but stops when I turn RIGHT

Noise gets louder every time I drive it.

-Josh

 

Just because there is grease still on the cv joints doesn't mean they aren't beginning to fail, and thus make noise, but I don't think that's your problem. Did the squeak just begin after you lubed the driveline or was it a preexisting squeak?

 

I have heard the noise before, but it was when my passenger rear wheel bearing was on its way out, it was not nearly as loud though. The rear axle was rebuilt earlier this year but I wouldnt be surprised if the shop did a half assed job.

 

Remove the rear drive shaft n replace the U joints.

 

OOOOPS never mind I see you kinda did that.

 

OK then CV boots NEED to be replaced.

 

Purchased new (well remanufactured) CV axles today, Ill be installing them tomorrow. Ill let you know how that goes.

 

alright gents, Both CV's replaced and the sound prevails.

 

Is it chirping at the wheel speed, or the drive shaft speed? At 20mph, the wheel rotates about 4 times per second. The drive shaft rotates about 4 to 5 times faster.

 

you know, i have the exact same thing going on right now. and it seems like it started the last time i greased everything up. going down the road it sounds like a chirp chirp chirp. speed dependent. if i brake hard it goes away for a minute. it comes and goes. had it on the lift the other day and did a quick checkover, didn't see anything obvious. it never makes noise when i have time at the shop. i'll keep up on this thread if i figure mine out.

 

Im starting to think its in the rear end, everything else on the drive train is good with the exception of the suspension, but the sound is wheel speed dependent. The U-joint that I didnt replace seems obvious but there was ZERO play and the joint seemed very smooth, any signs of u-joint failure I can look for?

 

RJR, I believe its wheel speed and not output shaft speed. very hard to tell though as its intermittent

 

If it's wheel speed it could be a bearing, or something in the brakes, like a wear detector just starting to touch the rotors, or an anti-rattle clip gotten cock-eyed. Does the noise stop when you apply the brakes, or just keep on without change?

You might try jacking up all 4 wheels, one at a time, and rotate them by hand to see if you can pinpoint the noise to one specific wheel.

 

All brakes are new and the rear end was rebuilt a few months ago, I tried rotating all wheels with the truck jacked up but didnt hear anything

 

Ill pull the drums off when I get a chance and make sure everything is good to go

 

all u-joints replaced on the rear shaft, cv's done, front bearings look good and are freashly greased, the noise is VERY loud, and silences when i take a right turn other than that its constant now.

 

Can you unlock hubs and see if sound goes away? If not, remove front drive shaft. If noise is still there, put front shaft on and remove rear shaft and drive in 4wd ( really front wheel drive). This will help isolate if the shafts are to blame or what end of the truck it's coming from.

If that doesn't work, maybe check backing plates on rear drums. Sometime they can get bent when used for leverage while removing drums. They could be distorting as truck heats up.

After that check dust shield on rear pinion - could be rubbing.

Could also be a stick-on wheel balance weight rubbing somewhere.

Is the front end tight? A loose tie rod, ball joint, idler arm, steering damper or bushing could make noise.

That's all I got... Good luck.

 

I have ADD/Fixed hubs, if im not mistaken my front shaft does not rotate in 2wd, just the cv's? correct me if I am wrong here. Ill pull off the brakes and check out the backing plates but I dont see how it could get louder over time if metal from the backplate is being worn down.

I have an audio recording of the sound (m4a format) but Im not sure how to post this.

 

turn up your volume http://www.youtube.com/watch?v=hUxTM...ature=youtu.be

 

I listened to it a couple of times but the wind noise was all I could hear. Can you tell where the noise is coming from, front, middle, rear? I don't know if 4runners have the centre or hanger bearing on the rear driveshaft, mine would do that, once it warmed up it would squeal. Is there a place in town that has a dyno? I had a bad vibration - ended up being my driveshaft was out of balance - and I found it by using the dyno, maybe that would at least help you isolate where the sound is coming from if you can take a good look while its running at highway speed.