How wide should wheel spacers be?
The size spacer you need will be equal to the thickness of the washers used. If a spacer greater than 5mm is needed, you may need to also purchase extended lug studs or purchase wheel spacers with studs. via
Are 5mm spacer safe?
It will be safe. While I have switched to extended studs which makes it less of an issue, 5mm spacers are not going to affect the holding power of the lug bolts much. If you are concerned, you can buy 10 extended lug bolts to recapture what is lost. via
Do you need extended lug nuts for spacers?
Actually, yes, you need longer bolts when using 10mm spacers. Never try to use the stock bolts on the 10mm spacers. There won't be enough thread engagement to properly keep the wheels secured. via
Why not to use wheel spacers?
Secondly, installing wheel spacers on a car increases the leverage on the wheel bearing. The larger the spacer, the larger the leverage becomes. This reduces the life of the wheel bearing as they are not made to take leverage forces and can therefore wear faster, increasing rolling resistance and power loss of the car. via
What is the point of extended lug nuts?
The real purpose of extended studs is so u can run rims with spacers and still have enough stud to be caught by ur lug nut. Drag racers have extended studs as they're required by most tracks if u r running lensos/bogarts/welds. via