2 New Tyres Then 2 Wheel Studs

[NORTHERN_LAD]

Yesterday I had 2 new tyres fitted to the rear wheels.This place is not a tyre specialist but a large independant garage that fit for Black Circles.

I have used them before when I first bought the car to fit new tyres on the front and the fitters used a torque wrench for the final tightening but this time snapped 2 wheel studs. Of course it wasn't their fault and blamed "someone with a windy gun" for over tightening them.

They replaced them FOC but I wonder if this is common on the RAV. When I bought this car in April it had new rear shockers fitted and of course they could be the culprits.

As I use the car to tow a caravan, I am now considering replacing all the other studs on the rears.

Your thoughts would be appreciated.

regards

Keith

[anchorman]

Never known it without the stud being abused first. I am dead careful with wheel studs. The stud is well oiled and I oil between the captive washer and the nut so there is no friction there and I get a true torque setting. You don't need a super calibrated NASA torque wrench, it is more important to get them tightened equally.

Tyre fitters tend to wang them up with a gun then click a torque wrench over them just for show. By that time the air gun has probably taken them to twice their recommended setting - brilliant.

[Hoovie]

I would be inclined to replace the whole set personally, for the cost of that against peace of mind and chance of studs being weakened.

I take off nuts/studs with Air Wrench but always replace with standard manual wrench and torque wrench to finish.

[Big Kev]

Oil between nut and captive washer in order to get true torque........absolute stonker taken on board.

So for TAPER nuts on normal wheels on Funnerburd Too, should I oil mating faces slightly..........?

Always thought that lubrication of wheel STUDS lead to over tightening ?......Pish.......?

[voyager t180]

A tip I got from an ex mechanic mate was to always slightly UNDER torque the locking wheel nuts,those being the easiest to round off when overtight and then a swine to try and remove.

[battleaxe]

Mine came out of the 20000 mile service with a snapped wheel stud, could clearly see a flood in the stud, but mr T wanted £33.00 to fit new stud, pointed out the floor to the erk with the tie but was as normal fobbed off and basicly told I did not have a clue after 55 yrs as engineer, upshot he gave me a new stud which took 20 mins to change after wheel was off.

B-A

[gjnorthall]

They say that an elephant has a good memory but a bolt or stud never forgets. If you tighten a fastener once beyond it's yield point, it will deform and not recover and will likely fracture when retightened. Manufacturers usually specify torques for fasteners at around 60% yield so theres a fair margin for error. However even a £30 impact gun will churn out 240ft/lbs of torque if not limited - 3x the specified torque of most wheel fasteners. Hardly surprising that wheel studs fracture! In addition - over-torquing damages the nut mating surface on your expensive alloy wheels.

There are probably as many people who support lubricating studs as don't. Torques are specified for clean dry surfaces - so lubricating a thread will marginally increase the clamping force for a given torque. However that's no big deal and there really isn't a right answer on whether to lubricate.

On alloy wheels - it's usually recommended to re-torque the fasteners about a 100miles after wheels have been refitted. Do this by slightly backing off to break the seal - before re-torquing.

Finally apply a smear of anti-seize or grease to the mating surface of the wheel hub (although some frown at this). If you've ever seen them getting a seized wheel off a hub (usually rears) at a tyre depot - you'll understand why - usually by whacking the tyre wall.

[voyager t180]

Great info there Gareth.

As with most things mechanical,things are never as simple as they first appear.

[anchorman]

Kev.

I always lubricate the thread so the nut goes in with as little friction as possible - you want to measure the resistance of the seat and the resultant back pressure on the thread, not the crud making the nut tight on the thread. You can oil the face of a tapered nut but it will just push it out so I tend not to. On the F1 nuts, you oil between the washer and the nut but not the surface that contacts the wheel. This photo shows the washer and no, it isn't my fingers it is a pair of gloves!

GJ

I always brush a bit of grease around the hub spigot. I never use coppaslip crud.

[Hoovie]

Finally apply a smear of anti-seize or grease to the mating surface of the wheel hub (although some frown at this). If you've ever seen them getting a seized wheel off a hub (usually rears) at a tyre depot - you'll understand why - usually by whacking the tyre wall.

The Tyre Pressure/Torque Chart I had for all manufacturers had guidelines about using anti-seize for various makes - some recommended it, some didn't, some did for some of their vehicles and not for others - the rational behind yah or nah I don't know but there must be some.

I was at a Citroen garage waiting for 4 wheels to be taken off a C5 so I could take them away to fix and the guy removing them was kicking them hard as he could to remove as they were VERY stuck on. Annoyingly, he damaged the fronts even more when they came off and rolled around the workshop floor :( so more work for me (but not more money)! His technique was not impressive!!

Another time, I was fixing 2 wheels on a Fiesta and it literally took longer to remove the two wheels from the hubs then it did to repair the kerbing.

I have a 8lb rubber mallet now to 'persuade' the wheel to separate from the hub where need be, but this is used from the inside and evenly around the wheel - and I do tend to use copper slip as GJ says.

[NORTHERN_LAD]

Thank you for your replies, I will change them all now. I'll give the dealers a ring and see what price they can do them for.

The tyres that where replaced where Yokohama's and DOT was before the car was registered so I think these where the original tyres in which case they where 4 years old and had done over 50k miles.

They still had tread left but where showing signs of cracking between the treads.

Keith

[voyager t180]

The Yokos are a great all round tyre.