I took my 91 GT for a MOT (roadworthy) and got an advisory for wear in upper ball joints. The guy who did the MOT is very unfamiliar with a 928 so wanted to get opinions before I replace the expensive a arms. Basically there is movement in the wheel when pushed towards the engine or pulled away from it. Car has under 100K miles.... from a few write ups these should last closer to 150K miles? Can this movement be the result of any other front end suspension component. Not sure how to check this myslef

 

I just did my suspension. It is a job. You basically have a steering knuckle held up by an upper and lower ball joint. I can't see how the lower control arm or the upper A arm will move unless you have significant structural issues. So if there is movement, it will most likely be a ball joint issue, but someone more knowledgable of the suspension mechanics may have an explanation. I have to land on the ball joints.

If you have to do the suspension, there are a lot of while you ar in there jobs to do as well. So make sure you think about doing other stuff.

 

Where on the wheel was the movement?
Pushing at the forward or aftward points? Or the top/bottom?

Forward/aft edges of the wheel - it could be the tie rod ball joints on the steering arms - you can buy OEM Lemforder ones from eurocarparts.

Top/bottom edges of the wheel - play in either the upper or lower control arm bushings (usually upper go first). You can get rebuilt ones from 928intl in the USA (they require your old ones back as a core - their rebuilder is in germany from memory), or you can buy new from Porsche for much moolah.

Also note - there is more play in 928 suspension than many other cars even when all brand new, due to the bushing orientation on the top control arms, so there's an outside chance yours are fine and its just the mechanic who's inexperienced.

 

Are your steering rack boots torn? My bet's on the tierods, though without knowing the plane of wheel wiggle it's always a guess.

 

Mine failed it's mot on the tie rods but got a warning on the control arm also. Both on the right hand side. Wonder if my difficult parking spot has increased the wear on that side. If changed my tie rods and will mot it soon. I'm assuming you are in the UK. If so hartech do rebuilds.

http://www.hartech.org/porsche_996_997_Boxster_reconditioned_parts_for_sale.html

 

Thanks Mike, I will check out hartech.

The play is noticed if you take the wheel at the top and bottom and push / pull toward and away from the car - both sides. Nothing was highlighted at last years MOT and the car did only 1500 miles since.

I was planning on buying the shocks and control arms (if needed) from the US and get it fitted in the UK. One rear shock is leaking and apparently they are different so he PO replaced only one at some stage.

 

Check your wheel bearings to make sure they are tight. They might give you the same feel unless you can actually see the movement at the top control arm.