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hub nuts
reck - 8/12/05 at 07:27 PM

Hi Can any one refresh my tied brain and remind me which side left and right hand hub nuts should be fitted? Should they resist the force of forward rotation or the drag caused by it?
Also does anyone really torque these nuts to the Haynes spec. 320Nm front and 270Nm back, i guess you should to preload the taper rollers, but my wrench is no way big enough.


DanP - 8/12/05 at 07:31 PM

tighten them in the direction they rotate when the car is moving forwards IIRC


flak monkey - 8/12/05 at 07:31 PM

Clockwise tightening on drivers side.

David


reck - 8/12/05 at 07:40 PM

thanks for the rapid reply.

any suggestions on the torque problem, other than get a bigger wrench!


bob - 8/12/05 at 08:20 PM

The way i always remember on the sierra rear is tighten towards the front of the car.

As for the torque,mine are not tightened up to the recomended poundage,if i did the wheels wouldnt turn.
I've met a few other builders that have the same problem.


hey nice garage

[Edited on 8/12/05 by bob]


NS Dev - 8/12/05 at 08:43 PM

Just a quick point...........................

this torque figure does not preload the bearings........if it did they would be in pieces!!!

It clamps the hub outer against the step on the hub inner. The machining tolerance of the hub is what sets the bearing preload on these hubs.

To be technical...............the high torque is required because the thread is a huge diameter and there is a limit to how fine it can be made (which would lower the required torque setting).

The thread is a huge diameter because Ford designed in a good degree of safety in the "keeping the wheels attached to the car" department.

The latter requirement sets the former, with the consequence that you and I, the aftermarket users, need to jump up and down a lot on a scaffold bar in order to torque them up.

In the real world, do them as tight as you can with a 1m breaker bar and your bodyweight, and with a new nyloc them will not come undone.


NS Dev - 8/12/05 at 08:45 PM

quote:
Originally posted by bob
The way i always remember on the sierra rear is tighten towards the front of the car.

As for the torque,mine are not tightened up to the recomended poundage,if i did the wheels wouldnt turn.
I've met a few other builders that have the same problem.


hey nice garage

[Edited on 8/12/05 by bob]


If you didn't tighten them fully because the wheels stopped turning, read my previous post for goodness sake!!:mad

the torque has NO FRIGGING THING to do with the turning torque of the wheel bearing


reck - 8/12/05 at 09:02 PM

Thanks for the sound advice.


flak monkey - 8/12/05 at 09:11 PM

quote:
Originally posted by NS Dev

If you didn't tighten them fully because the wheels stopped turning, read my previous post for goodness sake!!:mad

the torque has NO FRIGGING THING to do with the turning torque of the wheel bearing


Correct.

The preload on most taper bearings is infact very low. In their infinate wisdom the ford engineers decided to fix the running clearance into the hub design, rather than setting it by torquing the hub nut up to a specific value.

The torques are high on sierra hub nuts. However if you consider 320Nm in kgm force instead of newtons then you realise its actually only a force of 32.6Kg on the end of a 1metre bar...not as high as it seems

David


NS Dev - 9/12/05 at 04:16 PM

will just apologise for my abruptness in the replies above......I had a few drinks last night before coming on here!! doh!!



Sorry!


bob - 9/12/05 at 05:20 PM

No need to apologise,this particular thread just highlights why we should have a more comprehensive database.

The busier the site gets i find it harder myself to troll through the search system for the correct answers.


RichieC - 10/12/05 at 10:15 AM

quote:
Originally posted by bob
No need to apologise,this particular thread just highlights why we should have a more comprehensive database.

The busier the site gets i find it harder myself to troll through the search system for the correct answers.

Yep I agree, can never have enough "How-To" or sticky threads with the pertinant (sp) info readily available.

As far as your torque question goes, drop into a local garage who deal with HGVs and theyll do it in about 2 mins. Thats what i did and I also discovered an emmisions tester and brake rollers - free use whenever i want - Lovely jubbly

Rgds

Rich