wheel nut/bolt grease

[Richard_Hamilton]

Yes, the workshop manual says you should use an aluminium paste (Castrol Optimol TA or similar) on the threads, and under the head, but NOT on the spherical face which contacts the wheel. As for torque, it used to be 130 Nm for Gen 1 cars, but the workshop manual says you can also use 160 Nm: 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.) Edit: Just to clarify:

 

[stephenbailey]

Hi Guys
This is probably one of those questions that owners will have different opinions on.
Should i be using a small amount of aluminium grease on the wheel bolts before replacing my wheels
On several occasions the bolts have been fairly difficult to remove. After speaking to several people they advised a touch of aluminium grease on the threads or between the wheel & hub to aid future removal
I know that when Nissan service my van they always put copper grease on the wheel bolts !!
Also, Can anybody advise me of the correct torque settings for the wheel bolts ( 2006 cayman S- 19" wheels)

Many Thanks

Steve

 

[AndrewT]

Yes, the workshop manual says ..........

Richard,

Are you referring to a workshop manual that is for the trade only or is there a workshop manual available for diy owners? I'd like a reasonably priced manual to suit my Gen 2 2.9 Cayman (if anything Porsche be termed 'reasonably priced' []).

 

[Richard_Hamilton]

Andrew - Porsche don't do the manuals in PDF format any more. The information comes from the Porsche PIWIS TSI online system, to which you have to subscribe. A full subscription with unrestricted access is very expensive, and although there is a pay-and-go option, even then it is about 1.30 Euros per item to access.

 

[Motorhead]

Richard,

Any idea why the bolt torque was increased from 130Nm to 160Nm from MY 2012? It's a bit confusing since I've always used the lower value and unless there were issues with bolts working loose under certain circumstances, I can't see why two values are allowable.

Answering my own question, perhaps there was a design/spec change from MY2102 which prompted the recalibration and the 160Nm was introduced across the whole Cayman range to avoid confusion at the dealerships.

Mind you, I'm always dubious about torquing bolts to spec as things like thread hang-up and dirt or grease under the bolt head can lead to an erroneous torque value; but probably more consistent that just "nipping them up".

Jeff

 

[stephenbailey]

Hi Richard

many thanks for the info & tech sheet. I will buy some of the grease before next doing my wheels. I've heard differing opinions about greasing bolts so it's good to have it properly confirmed.

also thanks for the torque settings

cheers Steve

 

[Motorhead]

Steve,

I've a feeling that you can buy Optimoly TA paste from a Porsche dealership - probably a small fortune for a tiny tube - but I bought a 100gm tin from here ages ago and have hardly used any:

[link=https://www.motobins.co.uk/displayfinal.php?function=show&subs=098e&title=EXHAUST+NUTS]https://www.motobins.co.uk/displayfinal.php?function=show&subs=098e&title=EXHAUST+NUTS[/link]

Alternatively, if there's a BMW motorcycle dealership near you, you may be able to get a tin from them.

Jeff

 

[Richard_Hamilton]

Jeff - 160Nm is also specified for the 997 Gen2 from MY2011, and as an option to 130Nm for all other 997s retrospectively. 991 is also 160Nm. I have no idea why they changed it, but I suspect it must be for good reason.

 

[stephenbailey]

Hi jeff

thanks for that

ive just ordered some aluminium grease from seller on ebay

its not Optimol ta paste but is an aluminium grease/paste for use on threads etc

I will use the tech spec Richard sent me to make sure I only apply where required.

Cheers steve

 

[Buddy]

Wasn't there something a short while ago about not over tightening the locking nuts as they could split?

 

[AndrewT]

Andrew - Porsche don't do the manuals in PDF format any more. The information comes from the Porsche PIWIS TSI online system, to which you have to subscribe. A full subscription with unrestricted access is very expensive, and although there is a pay-and-go option, even then it is about 1.30 Euros per item to access.

Thanks Richard.

 

[Mikebarry202]

I remember years ago I did a project for my HNC learning about clamping forces (torque settings) and the effect of losses applied due to friction.... The logic is to apply a thin layer (the right kind) of grease (to the right places) to reduce friction and therefore end up with more clamping force.

I can't remember exact statistics but it is something like 85% of clamping Nm can be lost without applying grease (dirty/rusted threads and surfaces) but when applied the numbers change to achieve 85%. Obviously you won't get more than you put in, so a torque setting of 100 Nm for example won't achieve more when greased...... I apply grease/oil (dependant on the location) irrespective of manufacturers recommendations, although thread lock helps reduce friction too.

Maybe this logic has something to do with Porsche's stance as mentioned above regarding 130Nm or 160 Nm?

 

[stephenbailey]

Hi Mike

when described like that makes common sense, cheers

Kevan

i think there was an old thread about over tightening wheel bolts- that's why I've now got hold of a torque wrench

( previously used size 10s )

thanks

steve

 

[Buddy]

It may have been the lock bolt sockets that split on the locking bolt, either way a problem but replacement sockets may not be all that easy to obtain although I would expect a Porsche Centre to have a set for their own use should anyone have such a problem. I have at times used a small amount of copper grease on the wheel bolt threads, better to use something similar than assemble dry. We did find on my sons Boxster S that the wheels had been fitted at a dealership and the bolts had no lube, they took some removing due to corrosion, I greased them lightly and ran the bolts in and out to ensure all of the thread got some protection before we refitted the wheels

 

[Melv]

Copper grease on threads and 'mating faces'...... next question perlease!!

 

[Motorhead]

Although Porsche recommend greasing the threads, VW state specifically that they must never be greased or oiled. Every year when I remove the wheel bolts on my Golf they're always so badly corroded that the supplied box spanner is woefully inadequate and I have to lean on my breaker bar to shift them. Strange that different manufacturers take diametrically opposed views.

Jeff

 

[Richard_Hamilton]

Although Porsche recommend greasing the threads, VW state specifically that they must never be greased or oiled. Every year when I remove the wheel bolts on my Golf they're always so badly corroded that the supplied box spanner is woefully inadequate and I have to lean on my breaker bar to shift them. Strange that different manufacturers take diametrically opposed views.

Jeff

I guess that is why Porsche say specifically NOT to grease the bolts on a Porsche Toureg (Cayenne). []

 

[Motorhead]

I presume that the same applies to the Macan (Audi Q5) Richard?

Jeff

 

[am1985uk]

I guess the reason that you need to follow the manufacturer's recommendation is that the torque setting has two components, one to overcome friction and one to stretch the bolt (within elastic limits). Lubrication will reduce the friction characteristics significantly, thus if you use the same torque setting on a well greased bolt you will increase the bolt stress, possibly beyond the elastic limit.

I don't think there is one right answer to the question 'Grease or don't grease' - the important thing is to only grease the bits the manufacturer says you should and then to follow his torque recommendation.

Regards,

Alan

 

[Richard_Hamilton]

I presume that the same applies to the Macan (Audi Q5) Richard?

Jeff

Yes, that's correct Jeff - no grease for the Macan bolts, and 160Nm like the Cayenne. Before you ask, Panamera is no grease, and 180Nm.