Noise from the front end that I can't figure out

[triplevision]

I decided to do some much needed TLC to my 02 LT TB. I work at a tire shop and had my buddy put it up on the rack to see what the front suspension all needed to set the alignment and get my power steering back. He ended up giving me a laundry list of parts to replace: Lower control arms x2, Upper Ball Joints x2, CV shafts x2, Wheel hubs x2, and a rack and pinion. We also ended up getting a PS pump as well. After a couple of nights after work and a couple of hiccups (16 MM vs 14 MM steering racks) we got it done.

After we got it on the ground and did an alignment (-6 total toe before the alignment if anyone was curious) I started to drive it home. While driving the front end started making this awful noise. It sounds like the wheel of fortune wheel clicker but much more muffled. And the noise only happens when I coast or brake. The car drives excellently when accelerating and there is no noise at all. But it makes quite a racket when coasting. There is also a tinny grinding noise but i think that is the dust shields rubbing. I put the wheels in the air and the driver side spins pretty freely but the passenger side has more resistance per se. I couldn't hear a noise when spinning them by hand.

One thing I did notice is that the water pump is essentially shelled out. I can almost pull the whole fan off of the pulley by hand. I plan on fixing that here soon when the parts get here but could that be making the noise. My buddy things that the bearing has so much play that the noise is being cause by the impeller rubbing inside of the housing.

I'm quite honestly stumped. Other places have mentioned the diff but it never made this noise before the overhaul. And i filled it with 75-90 before i buttoned everything up. 4wd still engages and makes no difference in the noise. I have shut the engine off to coast while it's moving and the noise is still present. So I think it's a noise in the driveline.

If anyone has any ideas please let me know. I need a good winter mobile up here in the great white north and I am so disappointed that all of this work came with further complications.

 

[Mooseman]

You say that 4x4 engages but did you confirm that the front wheels are actually locked? Maybe the disconnect is not working and the the dog gears inside are rubbing or not disconnected right. Another possibility is the intermediate shaft that is stripped.

Stripped Intermediate Shaft

If you put in 4hi and lift the right front wheel, you shouldn't be able to turn it.

Other than the water pump, I don't have any other ideas. Maybe pothers can chime in with some suggestions.

 

[TollKeeper]

Did you replace the Stabilizer links? Or Re-Use? That can cause that noise.

 

[triplevision]

I'll have to check that today and see for sure. I'll update when i am able to check it.

i looked at the 02 to 05 service manual and it mentions backlash adjustment on the ring and pinion or replacing ring and pinion on "noisy while coasting."

 

[triplevision]

Re-used stabilizer links but they have no play. The guy i worked with has been doing this for around 30 years and he recommended not to replace but I'll look into it. Any advice on checking functionality?

 

[TollKeeper]

I dont honestly. My fronts and rears are OEM, at 213k miles, and only now just starting making noises.

 

[triplevision]

Some more details-on the first start of the day, the noise is not present or at least not noticeable. The sound gets louder when going over bumps. And by bumps I'm talking like traffic calming dips. When the nose dips down it gets loud then the nose comes up it's quieter. It's also constant with wheel speed and frequency adjusts to the wheel speed. Higher speed coasting means the sound is higher in frequency.

 

[TollKeeper]

So its suspension related. Need to check front and rear for this. Just because it sounds like its coming from the rear, doesnt mean it is!

Up Front
Upper control arm mounts
Upper ball joints
Lower Ball Joints
Lower Control Arm Bracket Bushings
Tie Rod ends (inner and outer)
Strut Mount Insulators/Bushings
Stablizer Links
Stabilizer bar bushings

Out back
Upper control arms, and bushings
Lower control arms, and bushings
Lateral Link/Torque Arm, and bushings
Stabilizer Links
Shock Mount Bushings
Stabilizer bar bushings

And also for play in the front and rear drive shaft.

 

[triplevision]

I should also mention i can feel it in the brakes, floorboard, and steering wheel. That leads me to believe it is coming from up front.

 

[Chickenhawk]

I would suspect the wheel bearings. Even if you replaced them, certain brands have a higher likelihood of defects right out of the box, or it could be the wrong bearing put into the correct box. That has happened before. Does the sound get louder when turning at higher speed in one direction and quieter when turning the opposite direction? Does it make a rhythmic thrumming sound at highway speeds? Do you get any ABS noises at low speed as you come to a gentle stop?

An experienced mechanic can feel a bad bearing when on a lift with the wheels off. And, by the way, the traditional method of defining which side is bad, such as it gets louder when turning toward the bad bearing and quieter when turning away from the bad bearing, does not work on our platform. Half the time, it is the other way round.

 

[triplevision]

I thought wheel bearings too but it's not a constant sound. There are no clicks or humming when turning in a certain direction. It is quiet when accelerating or even feathering the gas even in turns. The noise only happens when decelerating by coasting or braking. I did a 70 mph hard brake and it made the noise quickly when the brakes were applied then slowed down with wheel speed.

 

[triplevision]

The mechanic i did this job with has been a mechanic for 30 years. He thinks the wheel bearings were fine.

 

[triplevision]

We replaced the wheel bearing tonight and the noise isn't as bad as it was. It's still present on turns but not when decelerating. We also replaced the brakes and that fixed the grinding noise for the most part. I also replaced the water pump. We put it in 4hi on the lift and both wheels spun when they were off the ground. Whoever said the wheel bearing, that was a good call, the one we put in was shot from the get go. I'm now thinking it's the cv axle but i honestly don't know.

 

[triplevision]

Just an update for everyone who wants to know. We put it up on the lift to change the front diff fluid because we thought, what the hell why not. The noise is the front diff, don't know the exact cause but it is the front diff. The gear oil looked like silver craft glitter and there is a bearing/seal going out on the oil pan side of the housing.

 

[Mooseman]

Not the first time we've seen that happen unfortunately. The whole unit will need to be replaced and it's not an easy job neither.

How to remove front differential from the top
How to remove front differential from the bottom (easier)