Are you sure it’s not the pads rubbing the disc?

If the bearings are on the way out there might be a bit of play allowing the pads to contact the disc.

Ah sounds like mine. Makes a horrible screesh and the chain goes slack, as if the freehub is dragging (must be much more resistance than the rear mech tension). Thought it was the freehub, but inside was sparkling clean. Thought it was the rubber/ptfe seal, but that is perfect too. What I did notice is the axle is bent, but only very very fractionally. I found a tiny swarf of metal inside, but no idea where from. All bearings are perfect. But the resistance caused by everything when the freehub is put back on is imho far too high. Worked fine for about 50km after relubing, then started again.

I just replaced the wheel.

I had this too. The cassette had a lot of movement on it as well. There is a large white nylon washer in the free hub body and this had worn. A kit from America arrived pretty quickly and was easily fitted. Its also half the price of a free hub body. Check ebay for these kits. This sorted it. Also, check that the axle is just nipped up, not too much as this crushes the bearings and causes drag. I dont lube the pawls, just a thin grease on this nylon bearing.

HTH

Your freehub has had it. Take it back to the shop, it’s a warranty job. I’ve been through a couple.

The screeching is a symptom that the the nylon bush is running dry, and that you’ve not lubed your freehub in a long time

Biggest problem is that you’ve used grease to lube it, its the wrong stuff, and will kill your wheel quickly.

Take it apart, strip all the grease off, relube liberally with light mineral oil as instructed in the youtube video, and it should be fine, (if its not been permanently damaged already…)

I have finally fixed this connundrum. Well I didnt but that very nice man the Hub Doctor did. Read his message to me (below), it is all very clear now!

I have stripped out the advertising links so that the mods don’t get a grump on (again)

Hi Chris,
I have a solution to the worn out rear hubs and plastic bushings. First the
reason that it howls while coasting is due to the excess clearance around
the bushing and journal. The freehub \ cassette assembly is much like a
spinning top while coasting. When the plastic bushing is worn it allows the
cassette to wobble. When it (the bushing) lands on the hub it rings the
cassette assembly. The horizontal gouges in the hub snout are the result of
the freehub ratchet contacting the hub while you are pedaling and the
cassette is stationary with the hub. Your hubs are worn too severely to
replace the bushing. Besides the bushing journal is smaller than the outer
hub snout so there is no way to assembly it.
Regarding the pawls, it could be that new springs temporarily alter the
harmonics of the freehub. Two extra sprigs are included in case they are
lost during assembly and not to mount extras.

The solution is the HubDoctor Pro kit. It replaces the inner bushing with a
hybrid ceramic ball bearing that will give years of service. It mounts
behind the worn shoulder in your hub. Complete instructions are included.
Your freehub will function like new again. I can invoice you $39
each directly with Paypal and ship Priority US postal for $13.25 (up to 5
kits) or first class 1 kit for $6.25 or two kits for $9.50 usd.
To view the kits please review this link.
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
You will notice that the kit fits both road and MTB and Campy or Shimano
style Mavic freehubs. The outer freehub bearing is also included.
If you would like to convert to Hybrid ceramic wheel bearings with Si3N4
ceramic balls and chrome steel races I can provide these for $26 each for
both front and rear wheels. You get 4 bearings (since you allready have the
outer freehub bearing included in the kit). These are very good quality
have are not prone to seizing due to rust.

Thanks for the great pictures!
Best Regards and Happy New Year,
Jeroen Bosboom, HubDoctor LLC