I want to know if it's safe to ride with 5mm spacer on rear wheel on stock lugs? or do i need to extend the lugs?

 

You need to extend the studs, the lugs are fine

 

I thought only 10mm and up spacers you would need extended studs?

 

I thought 3mm was as far as you could go and still get the required 7+ full turns on the lug.

 

there must be a good reason why all 5mm spacers designed for our cars come with extended studs?

 

yeah, i meant extended studs, not lugs lol. i'm sure you all know what i meant. the reason why i'm asking is i'm on 19x11 + 17 rear, i'd like to put 5mm so it's +12

 

the problem with just a spacer is that your wheel wont be hubcentric anymore... the only thing centering the wheel will be the lugs, and thats not good.

you should do it right and get longer lugs and hubcentric spacers.

 

Actually 5mm is still hubcentric , but yes you will need longer studs. www.ichibausa.com

 

I just did 5mm spacers in the rear and yes you need longer studs. If the new studs are grade 10.9 then thats 170,000 psi tensile strength, for comparison arp studs which are the end all be all are 200,000 psi. H&R provides 10.9 grade studs with their spacers. Stock studs have 13mm of engagement for a 12mm stud, The front studs are about 1mm longer that the rears. I just like to measure and inspect the things that are keeping my wheels on the car, being I track it.

 

my 2 cents... replace w Nismo extended studs. my oe studs were
in bad shape when I finally pulled them at 50k. I also believe, like
everyone else, that you will need to extend the studs with virtually
any size spacer...

 

Good point. Here's a guideline from drag racing requirements: lug length must be at least twice the diameter of the lug. Example:

remaining threads: 10 mm
Diameter of lug: 5 mm

Its a GO.

 

The answer is, kinda. You can get away with it, but it's not really the greatest idea. If you do, make sure you check your lugnuts very frequently with a torque wrench. Keep in mind that the pads on different wheels have different thicknesses, so some will leave more threads exposed while others will leave less.