Wheel nuts torque

[gmcraib]

It says in the manual to torque the wheels to 130nm.
My torque wrench only goes up to 110nm, are there likely to be any issues?

I calculated the distance needed to reach 130nm with approx the same force (ok so guess work) and attempted to apply with a slightly extended wheel brace.

Should I just go out and buy a new torque wrench?
(I have two already)

 

[Lancerlot]

On the basis you're not confusing nm with lbs.ft, then yes you should purchase another torque wrench. Small price to pay for safety and peace of mind, I would have thought.

 

[Geoff_Fields]

Only £24 from Machinemart http://www.machinemart.co.uk/shop/product/details/cht141-1-2in-drive-torque-wrench

 

[Motorhead]

Other than the fact that a torque wrench provides a degree of consistency for tightening nuts and bolts, I always treat torque values with a degree of scepticism. The aim is to provide the correct tension in the bolt or stud via the application of torque and this will be affected by the amount of friction between threads and between contact surfaces under nut and bolt heads, which can vary considerably dependent upon the application. Wheel bolts and nuts, for instance, operate in a very dirty, gritty and corrosive environment and are not always spotlessly clean when a wheel is removed and replaced. [Have you ever seen your average tyre fitter clean the bolts/nuts/wheel before refitting the wheel?]. That said, I agree with Lancerlot - just go out and purchase another torque wrench with increased capacity. I use a Draper 30357, picked up from Amazon for about £24, which is a good general-purpose wrench. The main thing is to ensure that your wheel bolts are tight - you don't want to have the wheels falling off..!! Jeff

 

[Lancerlot]

The wheel bolts/nuts need to have clean threads. The underlying factor with incorrect torque is the frictional variation present between the contact surfaces. This can be reduced by using some sort of friction-reducing compound. Porsche suggest a smear of Castrol Optimal Paste TA on the threads. This is an aluminium based paste, also used in the latest centre-lock wheels.. It is important to provide an even pre-load to each wheel fastener and the use of a torque wrench is therefore necessary to achieve this. This needs to be accurate and used correctly too. I've seen tyre fitters use the torque wrench correctly, then "give it bit more to be on the safe side". [] This is not good workshop practice as overtightening stretches the threads and imposes undue stress on the fasteners that could eventually leads to failure. For reference purposes 1 Lb-Ft = 1.35582 Nm.

 

[Motorhead]

Quite..! Interestingly, Optimal TA is an aluminium-based paste recommended for its anti-seize (rather than lubrication) properties by BMW for its exhaust system nuts. Undoubtedly the OPCs charge an arm and a leg for small sachets but 100gm tins are available here for a resonable price: http://www.motobins.co.uk/displayfinal.php?function=show&subs=098e&title=EXHAUST+NUTS Jeff

 

[Lancerlot]

Also available in tubes [link=http://www.motobins.co.uk/displayfinal.php?s=0&function=show&subs=240&title=OILS%2FGREASES%2FSEALANTS%2FCLEANERS+ETC&model=]Here[/link] Tech. sheet for those interested is [link=http://msdspds.castrol.com/bpglis/FusionPDS.nsf/Files/104BC52BC4CE1D06802577960030186B/$File/453856_XI_en.pdf]Here[/link] Regards, Clive.

 

[gmcraib]

I forgot I posted this, haven't driven the car much since but they are still tight. I calculated an approximate force applied by hand using T = F x R equation from the 110nm wrench and then worked out the R (length of wheel brace) needed to apply 130nm of torque using the same force (approx). It was just a workaround to get me finsihed but yes I will be buying the torque wrench although I am confident in my sums. I use copper grease on the bolts.