Mystery rear hub/bearing squeal
05-07-2010, 10:17 AM
#1
Racer
Thread Starter
Member Since: Sep 2009
Location: Oxford CT
Posts: 414
Likes: 0
Received 0 Likes
on
0 Posts
Mystery rear hub/bearing squeal
I have performed a forum search and I believe that I have the dreaded rear hub and bearing squeal that seems to happen to a lot of our C4s based on the number of threads the search came back with.
Description of noise and what seems to trigger it:
Noise sounds exactly like high pitched metal on metal brake squeal, not a click-clack u-joint type noise. However, braking and associated components are fine and braking does not trigger the noise. When the car is cold, I can drive for 45 mins to an hour without a peep. After that, turning hard right seems to trigger the noise. After the noise initially triggers, it's doesn't stay there consistently but comes and goes sporadically with right turns and the occasional straight lane driving.
I diagnosed driving in a straight line with a buddy walking beside the car. When the noise cooperated and appeared during the test, we found that...
At a slow 10mph the sound is consistently, "one and two and, one and two and" four per wheel revolution. For you musicians out there, like quarter notes on a single bar.
If I slow down to a crawl, I get one long single noise per revolution and then it repeats, like a whole note on a single bar.
To date, I have practically drowned all poly bushings with lube. I have pulled all brake calipers off and confirmed that everything is seated correctly and rear of pads (plenty of meat left) are lubed. All U-joints were replaced over the winter with new spicer parts and I did carefully check each cap and needle bearing before installing. The right rear bearing does not move north/south, east/west when I check it for play and outside of the noise, the car drives perfectly. Again, brakes work fine and there is no vibration at all at any speed.
So based on my forum search, I think I need to either:
- Remove the spindle nut and retaining washer and apply lube upon reassembly
- Remove hub bearing assembly and replace the teflon washers. Lube everything upon reassembly.
- Completely replace both hub bearing assembly and teflon washers.Lube everything upon reassembly.
Any thoughts or advice are welcome! This squeal is embarrassing and I need help!
Mike
Description of noise and what seems to trigger it:
Noise sounds exactly like high pitched metal on metal brake squeal, not a click-clack u-joint type noise. However, braking and associated components are fine and braking does not trigger the noise. When the car is cold, I can drive for 45 mins to an hour without a peep. After that, turning hard right seems to trigger the noise. After the noise initially triggers, it's doesn't stay there consistently but comes and goes sporadically with right turns and the occasional straight lane driving.
I diagnosed driving in a straight line with a buddy walking beside the car. When the noise cooperated and appeared during the test, we found that...
At a slow 10mph the sound is consistently, "one and two and, one and two and" four per wheel revolution. For you musicians out there, like quarter notes on a single bar.
If I slow down to a crawl, I get one long single noise per revolution and then it repeats, like a whole note on a single bar.
To date, I have practically drowned all poly bushings with lube. I have pulled all brake calipers off and confirmed that everything is seated correctly and rear of pads (plenty of meat left) are lubed. All U-joints were replaced over the winter with new spicer parts and I did carefully check each cap and needle bearing before installing. The right rear bearing does not move north/south, east/west when I check it for play and outside of the noise, the car drives perfectly. Again, brakes work fine and there is no vibration at all at any speed.
So based on my forum search, I think I need to either:
- Remove the spindle nut and retaining washer and apply lube upon reassembly
- Remove hub bearing assembly and replace the teflon washers. Lube everything upon reassembly.
- Completely replace both hub bearing assembly and teflon washers.Lube everything upon reassembly.
Any thoughts or advice are welcome! This squeal is embarrassing and I need help!
Mike
Last edited by npbassman; 05-07-2010 at 10:36 AM.
05-07-2010, 11:15 AM
#2
Safety Car
IIRC, that is a symptom of the washer. Unless someone chimes in with a better idea, I would start with that since they're cheap. Also, I don't think you lube anything on assembly, as far as the bearing and washer go. At least I haven't, and I've replaced 3 rear hubs on my car with no problems.
05-07-2010, 11:19 AM
#3
Le Mans Master
Yes-that is a sign of a bad bearing....the noise you hear is the rotor dragging on the pad/s from the excessive bearing slop. If it does it only while making right hand turns then address the left rear position.
Jack up the corner of the car on the wheel postion in question and grab the wheel each hand @ the 12 and 6 o'clock postion and check for play in the bearing....I bet you've got quite a bit of wiggle.
If there is a lot of bearing "wiggle" it is pretty safe to say that you'll want to replace all the U joints, coated spindle washers and the bearings at the same time. Also take a close look at the rear rotors for warpage and angled pad wear - depending on how long the rotors been rubbing you may need to "turn" your old ones or pick up a replacement.
Jack up the corner of the car on the wheel postion in question and grab the wheel each hand @ the 12 and 6 o'clock postion and check for play in the bearing....I bet you've got quite a bit of wiggle.
If there is a lot of bearing "wiggle" it is pretty safe to say that you'll want to replace all the U joints, coated spindle washers and the bearings at the same time. Also take a close look at the rear rotors for warpage and angled pad wear - depending on how long the rotors been rubbing you may need to "turn" your old ones or pick up a replacement.
