IT Motor Mounts, please send in your yes votes to the CRB

[chuck baader]

I'll use my car as an example. The whole rear suspension is an assembly bolted to the car in three places, each end of a suspension subframe, and the diff. All three have bushings. The rear control arms pivot off the subframe. The complete subframe/control arms/diff is the rear suspension. Chuck

[JoshS]

I'll use my car as an example. The whole rear suspension is an assembly bolted to the car in three places, each end of a suspension subframe, and the diff. All three have bushings. The rear control arms pivot off the subframe. The complete subframe/control arms/diff is the rear suspension. Chuck

Yes, in these cars (Chuck's is the same as mine) the differential is a stressed member of the subframe assembly. The whole assembly is the subframe and is attached in three places to the chassis, all with bushings. The rules already allow subframe bushings to be replaced.

This in my opinion is very different from a more traditional rear suspension. In other cases the differential is not a member of the subframe at all, but rather, hangs from it or the chassis (like a Miata). In those cars, I don't see how you could use the suspension bushing allowance to change the differential-mount bushings.