Board logo

Sierra rear wheel bearings torque
andrew-theasby - 9/6/11 at 12:40 PM

Been doing a lot of searching and it would seem 200-250n/m is the torque for the rear wheel bearings hub nut. Is this correct as it sounds way too tight for taper roller bearings, or are there other bearings available that this refers to? I've read about them locking up. I always thought normal ball bearings were as tight as you could get them and taper ones needed torqueing, backing off then running and re torqueing. Havent nipped them yet but 200+ will surely nip taper bearings too tight wont it? Or have i got the wrong bearings as the nut is a nylock, not one with a split pin. Anybody know for definite? Thanks

Doctor Derek Doctors - 9/6/11 at 12:47 PM

Sierra Rear Wheel bearing are normal bearings though aren't they? I'm sure mine aren't tapered roller bearing like the Cortina front bearings.

I could be completely wrong though.

tomgregory2000 - 9/6/11 at 12:48 PM

disc or drums?

Peteff - 9/6/11 at 02:11 PM

They are not tapered, crank them up. They seem stiff at first but once it's on it's wheels they soon free up.

Bluemoon - 9/6/11 at 02:35 PM

Sierra are not tapered roller. The pre-load is determined I believe by the machining, the torque setting is only to hold the nut on

Some have had difficulty with the bearing being to tight this might be due to rubbish getting in the way, worth making sure the assembly is clean on the mating surfaces (i.e. a bit of rust/grit may be enough to increase the pre-load). Not had mine apart so this is only an educated guess. As has been mentioned they will be tight ish to start with and loosen up after 100miles or so.

Dan

andrew-theasby - 9/6/11 at 03:48 PM

The ones i took out, and the brand new ones i bought are tapered...?
Its a disc braked axle

[Edited on 9/6/11 by andrew-theasby]

[Edited on 9/6/11 by andrew-theasby]

Davg - 9/6/11 at 05:30 PM

Andrew
despite what previous posts have said the sierra bearings are definately taper roller bearings!!!!!!!!!

Torque for the driveshaft nyloc nut should be around 200lb ft.

cheers D

flak monkey - 9/6/11 at 05:33 PM

Yes they are taper roller bearings. The running clearance is set by the machining on the half shafts and the bearing carrier not by a nut preload like on most. Odd, but thats how it is.

Your torque figures are correct.

andrew-theasby - 9/6/11 at 05:52 PM

Ok, thanks. How free should the splined end of the drive shaft be to run through the middle? I cant get it free enough to push through by hand, i have to draw it it on both with the nut for the last bit, is that ok?

Davg - 9/6/11 at 05:55 PM

Yep that is ok, the shaft has to be a very tight interferance fit with the inner bearing cage.