Tire change question

Some places advise tightening the nuts/bolts only partially while the car is jacked up, then lowering the car and tightening them fully. Probably because the jacks provided with cars for emergency tire changing are not the best, and may not necessarily be on flat, hard ground.

It doesn't matter as long as you get the nutz to the specified torque (100-140 ft-lbs).

That said, good luck getting the nutz tight while the wheel is of the ground and unsecured by anything.

Harry

You should apply enough torque to the lug nuts to ensure that the wheel is correctly seated prior to lowering it to the ground. Also, the nuts should be tighened in opposite pairs (or as close as possible in the case of 5 nut wheels) to ensure that the wheel is seated flat and not warped.

The amount of torque you can apply while the car is still up on the jack is a matter of judgement as far as the risk of knocking the jack over.

I don't usually have any trouble holding the wheel while I tighten the nuts with a torque wrench.

Ed

Harry Smith wrote:

Loosen and fully tighten the nuts only while the tire is still on the ground because it's not that difficult to make the car wobble around when the tire is in the air and you're applying a lot of torque to the nuts.

I personally don't know of any instances where a car fell off the jack because of that, but I've witnessed jack failures. In one I heard the car fall when a tire was being changed and the lift point flange bent, and in the other case a GM X-car bumper cracked on me while I was raising it to change a tire.