Overtightened and greased wheel nuts

[delbois]

For the past few years I have used my trusted Toyota dealer some distance from where I live, rather than the local Arnold Clark dealership, which is only a couple of miles away. Earlier this year circumstances dictated that I was unable to travel so had to give AC a go for the annual service. At the time I was pleased with the overall experience.  Today I got round to changing the wheels (I have a spare set of alloys with 'winter' tyres) and was very surprised to find (i) the nuts had been severely over torqued and I had a heck of a job removing them (the wife would have had no chance!) and (ii) all the wheel nuts and studs had been heavily greased. The attached picture shows copper grease on the hub and facing and a dollop of standard grease on the top bolt (the others had been already been cleaned by me by the time I took the pic).

My understanding has always been that wheel nuts should always be torqued 'dry' so I checked the manual which states: "Never use oil or grease on the wheel bolts or wheel nuts. Oil and grease may cause the wheel nuts to be excessively tightened, leading to bolt or disc wheel damage. In addition, the oil or grease can cause the wheel nuts to loosen and the wheel may fall off, causing an accident and resulting in death or serious injury. Remove any oil or grease from the wheel bolts or wheel nuts."  The combination of greasing the nuts and excessive torquing is clearly not good news. 

What hope is there when you can't trust a main dealer to perform such a basic operation properly.  I'll call AC tomorrow as it may stop the uninitiated mechanic(s) from doing this in the future but I think I'll be having a nice day out for next year's service!

[Swwils]

Manufacturer specs are always un-greased because otherwise the torque specs would be different. Not the case on some head bolts and such but yeah.

If you delve deeper the joint face should also be dry (so torque can be transmitted by the friction, and not by shearing the bolts) but lots of people put stuff there to aid removal.

[afropelican]

Copper grease on the hub face is fine - as it makes the wheels easier to remove. But yeah, the wheel nuts and studs shouldnt have been greased - simply cleaning with a wire brush if necessary is all thats needed.

Most grages that have invested in impact guns in my experience use them for everything! - I've even witnessed some removing spark plugs using them. I'm not one to Torque every fastner on a vehicle, and didnt invest in a torque wrench set until this year, but even so if they were using a breaker bar they would feel when its tightened up enough. Impact gun without a torque stick was definitely used in this case - especially as you struggled to remove a greased fastener!!

If you don't mind my asking: If you are competent enough to jack the car and swap wheels etc yourself, why don't you do the service yourself? Its likely just an oil change and maybe a couple filter swaps at this interval for a 2013 auris?

I've purchased vehicles with full dealership service histories before and noticed that some key maintenance has been missed out - and some fasteners have been snapped. This is why, when I can, I work on the vehicle myself - even though I have no driveway/garage, making it more difficult than it needs to be!!

[delbois]

Thanks Swwils and Afro

I think Swwills makes a good point about keeping the faces dry so that when they are clamped together the friction between them will prevent all the braking and drive turning forces being transmitted to the studs. The hub and faces were packed with copper grease so the friction between the plates would have been much reduced. Today's job is to remove the wheels and give everything a good clean.

Afro...there are a few reasons I don't service the car myself...firstly changing wheels is just about my limit and I'm getting too old to learn new tricks! Also having a full main dealer service history should help with resale and and any warranty/goodwill claims. I also get a 'free' hybrid check with the service which extends the warranty on the system. 

BTW I called Arnold Clark this morning and was told it is standard practice in their service dept to apply copper grease to the hub and faces and grey or copper grease to the studs to make it easier to remove the wheels. I also spoke to my usual Toyota dealer who said they would never do it. I've raised with Toyota UK to see if it's an 'issue' that need addressed i.e. either their manual is wrong or the main dealer is.

 

[mrpj]

Copper grease could affect the ABS sensors and shouldn't be used.

[delbois]

I received a fairly positive reply from Toyota UK who said they will raise the matter with the dealer. 

In the meantime I've degreased and rinsed all the gunk from the faces, studs and nuts back to their original clean dry state. Although it's now sorted it simply shouldn't be necessary. 

Presumably the thousands of Toyotas serviced and MOT'd at this dealer will have received the same treatment and their owners placed at unnecessary risk. 

[mrpj]

There is also advice, in the owner's manual, about not apply anything to the wheel studs.

I commented on a Youtube video about not greasing etc. the wheel studs/nuts in response to someone advising to lubricate them. I also quoted the handbook.

Some car repair establishment, in the U.S., disagreed stating they always grease the "lugs" because anyone living in the "rust belt" would not be able to slacken the nuts. Totally ignoring the fact that those nuts would be overtorqued - guaranteed! No doubt that establishment just use an impact gun to both release and tighten.