I believe in most cases the only difference between minimum requirements in "the big 3" (radial, rotary and impact) SAE specs and what could be required from an auto maker is the number of cycles, determination of a passing or failing test and possibly the methods used to calculate the test loads (mainly for radial and rotary fatigue) as well as additional measurements taken during the testing process to help validate an accurate test (deflection during testing, speed at which impact weight falls, torque loss during radial or rotary, etc.). If memory serves me correctly, SAE requires a minimum of 50K cycles on rotary and radial fatigue testing. Some of the gray areas in determination of what is a pass or failure may also differ between SAE and an auto maker. For example, a crack on a fatigue test may not necessarily be deemed a failure by an auto maker if it does not propagate during additional testing. I cannot recall off the top of my head if pass/failures are well defined in the SAE specs or not.
Also of note may be the road hazard impact test. As a supplier, my former employer was never asked to perform this test, but it was starting to see some discussion and popularity amongst our customer's product engineers. Would have been a real bear to try and design a wheel to pass this test, so I was glad it never was required of us.
As a supplier to 1 of the big 3 and several Japanese auto makers with a former employer, we were never required to perform strain gaging - that was for our own information only to assist in determining if FEA was giving us accurate results.
Tim Flater
NX Designer
NX 8.0.3.4
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