Wheel Spacers - Good thing?

[hemi43]

Originally Posted by argonaut

I must disagree wholeheartedly that "spacers" should not be used. So long as they are made from an appropriate material and are used with studs or bolts of the appropriate length to achieve the proper thread engagement then there is really no issue with a modest thickness spacer. The load path is still through the studs to the wheel, which sandwiches the spacer. So as long as toque and thread engagement are adequate, there should be no problems. Additionally for years different automotive companies have design cars that uses such "spacers" from the factory.

"Adapters" on the other hand can be even more dangerous, especially if not designed properly. In this design the load path is through the studs to the adapter, then through the adapter itself to the secondary studs, then to the wheel. So the critical failure point it the adapter itself. If I cracks or fails your wheel will decouple completely.

That said, I'm using 1.5" aluminum "adapters" (I still call these spacers, as they are spacing the wheels out, not adapting a different bolt pattern, but just semantics) on the rear of my blazer. I dont trust them completely but I inspect them regularly for cracks and fatigue. All-steel adapters would be a different story. You'll have to proceed at your own risk.

I certainly would not recommend that anyone use "spacers" without installing longer studs. In fact, even if you are using aluminum wheels you may need longer studs since the original studs are short, being designed for use with steel wheels.

I'n not sure what your background is, but I've been a Tool Maker for over 35 years and now have my own shop specializing in aftermarket race car components, so I do know what I'm talking about.
The problem with a spacer is that it puts too much load at the base of the stud, and that's where they fail. Using a longer stud will only increase the problem because the rim now has more leverage to snap the stud.
The face of the rim MUST be bolted to a non-movable surface like the axle flange or an adapter. I agree what you say about the load path of the stud, but what you fail to mention is that you have rotational forces acting on these studs and that where the problem lies.
Telling people to use a longer stud is not only bad advice, but dangerous advice !!

[jaros44sr]

Originally Posted by hemi43

I'n not sure what your background is, but I've been a Tool Maker for over 35 years and now have my own shop specializing in aftermarket race car components, so I do know what I'm talking about.
The problem with a spacer is that it puts too much load at the base of the stud, and that's where they fail. Using a longer stud will only increase the problem because the rim now has more leverage to snap the stud.
The face of the rim MUST be bolted to a non-movable surface like the axle flange or an adapter. I agree what you say about the load path of the stud, but what you fail to mention is that you have rotational forces acting on these studs and that where the problem lies.
Telling people to use a longer stud is not only bad advice, but dangerous advice !!

OK Hemi, you convinced me, I'll switch from spacers to adapters, any company you recommend, posted by another t&d guy with 50 years OJT

[hemi43]

Originally Posted by jaros44sr

OK Hemi, you convinced me, I'll switch from spacers to adapters, any company you recommend, posted by another t&d guy with 50 years OJT

I made my own for a couple reasons. One is that all this stuff is made in China out of crap material. Most of the ones I've seen look like they were machined from billet stock material, but in actual fact they are made from castings machined to dupe the consumer into thinking it's a quality product. I can't recommend a manufacturer, but you will get what you pay for. I would stick with an American company that guarantees they use 6061-T6.
The other reason I made my own is that they don't make a 6 bolt adapter for my Blazer because I upgraded my studs to 1/2-20. All I could find were adapters with the stock 7/16 studs or the newer 14mm studs which wouldn't fit.

It might be difficult to convert from spacers to adapters because usually the spacers are thin. The minimum thickness of an adapter to use IMO should be at least 1" thick. Anything thinner I wouldn't trust.