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Anybody knows the definitive answer to this? Are the suspension components any differents between the AWD and RWD 3IS?

Lots of aftermarket lowering springs are made for one, or the other. But as an example, why are the super downs made for both? And the downs have 2 distincts parts?

CLUM

The front shocks are different for sure, they mount differently to the lower control arm since the AWD fronts have axles--there is a "C" shaped mount that goes around the axle, connecting the shock to the lower control arm.

Since Tanabe says 1 model number fits both AWD and RWD, i'm willing to bet that's right. (You might as well call them to confirm). I was a test vehicle for them for MY15 350 RWD non-F and it seems like they are testing every iteration of the 3IS as they were specifically looking for a RWD base.

As for other companies making separate part numbers, it could be a variety of reasons. They might not have tested each different type of model and just assume AWD is different from RWD because the shocks are different......or maybe they changed the spring rates to accommodate for AWD usually being used in snowy climates.....or maybe they changed the drop amount for AWD because due to difference in curb weight...only the spring manufacturer knows for sure.

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Tanabe does list the same part number for AWD and RWD, but different numbers for F-sport and base.. Adds to the weirdness! lol! (Looks like there's a bigger drop on RWD)