Hi all,
a little warning.
As many of you know I swapped my 16" original turbine alloys for later X308 18" Asteroids about 2 months ago.
At the time my tyre guy said drop back a week later and he'd re-torque my nuts, so to speak.
So today, about 6-8 weeks later I finally did.
And I have 2 loose nuts, possibly stripping.
I had bought a new set of 20 genuine Jag nuts from Beachams here where I live. Never used, come in a bag with Jaguar Genuine Parts sticker on it.

Today, Noel the tyre man got out his quality torque wrench, set it for about 110 (I think lb-ft not Nm, but I will check with him), which he says is right for many Jag models.
18 nuts were spot on, but 2 on one rear wheel were loose and the wrench wouldn't click as he kept tightening. We both thought they were about to strip, so he stopped.
I then drove to Beachams and got 2 replacements (secondhand) and will get Noel to torque'em up tomorrow.

It raises the question about quality of so-called genuine parts however..

 

Check the studs. They may be turning in the hub. In that case no amount of torquing will accomplish the goal. I suppose you could check by torquing down a nut on each of the problem studs without a wheel on.

80 ft/lb is the usual number quoted for these wheels on dry threads. That's somewhere close to 110NM.

I use lube and tighten to "about right"

On another note, I just found a lug nut washer laying on the ground next to the car. Must have dropped off while being reinstalled ... a few months ago.

 

I thought all wheel nuts were 75 lb/ft

 

5 lbs one way or the other isn't going to matter. That's about the limit of accuracy in that range for most torque wrenches.

 

well, it gets better.
one stud has now stripped out of the hub - it fell out onto the floor of the tyre shop this morning. Another stud is spinning. So my rear wheel is held on by 3.1 wheel nuts at present.
I am sourcing a secondhand hub and getting it fixed next week.
the handbook states 88-102 Nm for the nuts. He had set the torque wrench for about 120-130, so therein lies the problem, I think...

 

Probably not. It's only 25 percent more than spec. There would be lots more head room than that.

More likely it was at some point in the past when the nuts were blasted on with an impact wrench. Now it gets to Noel, and he's the one who gets to discover the past damage while you are watching.

 

I m not pointing fingers, Plum. You are right. It is 18 years old and who knows what torques have been inflicted on it in that time?
He is a very careful meticulous guy who spent about 6-8 hours carefully straightening the bent Asteroids for me.
it is one of those things, and I would rather know about it in the tyre shop than at 100mph...

 

True. Noel seems like he has been very good all through the process of getting those wheels and the right tires on the car.

 

The final bit of this chapter:
this weekend I bought a torque wrench and a 22mm socket.
My rear hub was replaced 2 weeks ago.
I decided to go around all the wheel nuts, loosen them up, and re-torque them.
I got 3 wheels done, then my elderly ratchet 1/2" drive broke on the 4th wheel, they were that tight.
So the perfect excuse for another trip to Repco, and I came home with a new 1/2" drive ratchet handle and a 60cm breaker bar.

All wheel nuts now at 70 lb-ft (manual recommends 65-75 lb-ft = 88-102 Nm). I think they were up around 120-130 Nm - way too tight

 

I know that time is money but, really, with a wee bit of hustle it only takes about 60 seconds to properly tighten the lugnuts with a torque wrench.

Run 'em down *lightly* with the impact wrench and finish off with a torque wrench. Easy. I've done it a thousand times. Anyone can do it. No reason not to.

Cheers
DD