Rear suspension top mounts quick query..

[Gazmitchell]

Strut top mount bush and bearing , blue bush OE and bearings but why in the rear if it doesn't turn !!??

[Greg_S]

It was probably to keep the cost of production lower. The rears don't tend to do anywhere near as much as the front

[Lago Blue]

Greg is likely correct regarding a net cost saving, you may have noted how the entire rear suspension is a near mirror-image of the front...including the sub-frame, A/R bar, A-arms etc., and certainly the rears are much more lightly loaded.

The rear strut does in fact need to turn in at least two distinct circumstances, to allow adjustment of the alignment; and it does turn through a very slight arc during normal strut compression and rebound guided by the short rear drag link. in both cases it rotates in that top-mount bearing.

Although likely unintended in the original production design, another benefit to the service life of rear top-mounts besides having to simply carry a lot less, is that by using front-capable mounts on the rear, the ersatz gimbal-like play in the low-tolerance OEM INA thrust-bearing allows some mis-alignment to take place between the fixed near vertical center axis of the top-mount's captive outer shell; and the strut/damper shaft's varying vertical axis. This tilt change of the strut axis, which results from normal suspension travel, would otherwise be completely transferred into the bonded rubber and steel internal core interfaces of the mount body, further stressing, heating and distorting it, beyond that which already takes place; to its detriment.

BTW, if you are looking for the best OEM mount, thanks to Mance Etheridge, who proved it by testing many examples to failure, we know that the latest genuine and strictly dealer-sourced OEM green-painted Boge/Sachs mounts intended for the front of the V6 cars are the strongest, stronger than even the mythic "blues".

Attached is an example of what else is possible by leaving that bearing in place on the rear strut.