Mine came with Avos all round, but have since replaced the fronts with new Avos and rear with Protechs (it is an IRS model but don't think that changes much). My notes are a little unclear, but I think the front Avo are 150/100s and the rears were for sure 160/105s, which I presume relates to the open and closed lengths in some way. I replaced the units because they were rusty and the damping adjustment had seized (plus it had ridiculous heavy springs - 400rear, 450 front).

Nothing should be knocking or catching, unless you have the wrong length of damper or the wrong sized wheels/tyres (or wrong wheel offset). I would take the springs off and then with the car on axle stands jack the wheels through the full movement range of the damper and check the clearances. Note that on the coompression side they can move a little further in real use as the rubber bump stop will compress. You know the spring diameter so can measure between where the spring would be and the gaps to the tyre/inner wheel if you think that is the problem, though if they have touched there while driving there is most likely a mark on the spring.

Note that, in my book, springs should never be fully unloaded when the damper is fully extended as the collets could potentially drop out (e.g. when flying over a hump back bridge). After a lot of trying to sort out rear spring rates and ride height on the Protech units I ended up in this situation and added helper springs. I think the problem may have been that the Protechs were longer than the Avos, though MHS assured me they were the correct ones.


In seeking to undo one riddle, and find the true, I knit a hundred others new.