Wheel Spacers With Wheel Studs
Wheel studs protrude from the hub and help to locate the wheel to the hub. A wheel nut (lugnut) would then be used to fasten the wheel to the hub. The issue with using them with spacers is that it can actually push the wheel out too far, leaving you without enough threads to securely fasten the wheel nut. Here are some things to keep in mind when choosing studs and spacers -
- length of available stud sticking out from the hub
- brake rotor hat thickness (varies)
- wheel bolt bore depth (the depth of the hole in the wheel) (varies)
- spacer size
- number of turns on your wheel nut (6.5 turns or 10mm for a 12x1.5 stud/nut)
For instance, a TMS 75mm wheel stud usually has enough room left over to use a 10mm spacer. However, a big brake kit may have a thicker rotor hat than stock which would reduce your available space on the stud. As well, the thickness inside the bolt bore can vary a lot as well. A thicker wheel will reduce your available threads. The solution here is to use a longer wheel stud.
TMS Wheel Spacer and Stud Design in SolidWorks
(click the image below for a super-sized version)
This image was created by the TMS engineers in SolidWorks - a CAD program. All components are scaled correctly in relation to one another. Here you can see the relationship between wheel spacers, wheels, and the hub (wheel bearing). You can also see how brake rotor hats and wheels also play into spacer fitment.
This particular drawing is of a E36 M3 with a TMS 12.5mm spacer, a stock BMW brake rotor, a TMS 75mm wheel stud and TMS wheel nut, and a generic wheel design. There's a lot to look at on this drawing but things to pay particular attention to are -
- the fitment of the spacer (green) to the hub (red),
- the fitment of the wheel (grey) to the spacer (green),
- the thickness of the wheel bolt bore where the nut is fastened. A deeper bore will result in less threads for the nut to engage -OR- will require a longer than normal wheel bolt.
