torque value

[glenn duval]

Hi why is the wheel bolt value so high, 160nm. Am on my second locking wheel nut tool as they have distorted. main dealer tool not copy. My mate races a V8 holden in classic events. heavy car, And he only runs 120nm with no problems. My car will never be tracked. Many thanks Glenn

 

[AndrewT]

The Driver’s Manual for my 987.2 Cayman S specifies 96 ftlb. (130Nm). It also says to apply a thin coat of aluminium paste to the thread and between the bolt head and the moveable spherical cap ring but NOT on the bearing face which contacts the wheel. It mentions no different torque for the security bolts.

 

[Richard_Hamilton]

Porsche did increase the torque figure to 160Nm in MY2012. This is what the 987 workshop manual says:


Silver wheel bolts (up to model year 2011) = 130 Nm (96 ftlb.). 160 Nm (118 ftlb.) also permitted retroactively.

Silver wheel bolts as of model year 2012 = 160 Nm (118 ftlb.).

Black wheel bolts = 160 Nm (118 ftlb.)

IMO, using 160Nm on the locking key is a bit af an "ask". I do mine to 130Nm, and slightly less on the locking bolt.

 

[Motorhead]

Glenn,

I have a 2009 987.2 Cayman S and as Andrew points out the recommended wheel bolt torque is 130Nm. However I believe that the torque was revised to 160Nm for later cars in the 987.2 series but I don't know why.

The locking wheel nut tool is very poor quality, and being made from aluminium is damaged much too easily. I push it firmly into position to make sure that it's located properly and that's seemed to work ... so far.! I suspect that damage to the tool is most likely caused by the use of windy-guns during servicing and tyre changing activities.

I suppose it's not a bad idea to have a spare tool just in case.

Jeff

Ha! It looks as though Richard beat me to it. []

 

[Geoff_Fields]

The revised torque value seems unnecessarily high to me. Both of my current cars are 130Nm (non Porsche)

 

[AndrewT]

.....Silver wheel bolts (up to model year 2011) = 130 Nm (96 ftlb.). 160 Nm (118 ftlb.) also permitted retroactively.....

Thanks for the details Richard, is there a figure for rusty wheel bolts as found on my 2011 987.2? ??

 

[AndrewCS]

I have also `chewed` an adapter, my fault … for not ensuring perfect alignment prior to tensioning.

I then sourced four standard bolts and utilize these instead, now in use on my third Cayman @ 160Nm.

As regards `why so high` … engineering calculation for the application.

An improved design would be beneficial, the splined `steel to steel`version on my twenty year old Audi S4 is excellent. My GT4 owners manual shows this type of splined bolt / adapter but unfortunately it`s not what is provided.

`Grease` … all my cars have been 2012 onwards and none of the owners manuals have advised grease on bolt threads. It only being advised on the wheel guiding lugs of the hub.

 

[Motorhead]

With the ready availability of battery-powered impact guns and tools for removing offending adapters I wonder if it's worth using locking wheels bolts these days. They're hardly an obstacle to the casual - let alone the professional - thief.

Jeff