[maddog2020]

does anyone have the part number for the Audi ball joint boot that works on the S4 and later upper control arm ball joint?

Also does anyone know if that boot will work on the lower ball joint for S4 and later?

[Gary Knox]

Sterling,
I had these two options in my saved files:
BMW boot 31 12 1 109 077

Audi parts 431 407 377 A

I purchased the Audi ones and Stan K. installed them on my '95 last summer, as I'm no longer able to do much mechanical stuff.

Gary

[worf]

IIRC the upper and lower are the same.

I'll try to remember to check when I go out to the shop in a little while.

[Gary Knox]

I put in one new ball joint on each side, so only ordered 2 of the Audi boots.
G

[maddog2020]

all my boots were ok but during the disassembly they all got some nicks so I just want to replace them all while I'm doing upper and lower control arm bushings.

[maddog2020]

all my boots were ok but during the disassembly they all got some nicks so I just want to replace them all while I'm doing upper and lower control arm bushings. I'd rather not have to buy a $150 ball joint just because I want to replace the boot.

[maddog2020]

IIRC the upper and lower are the same.

I'll try to remember to check when I go out to the shop in a little while.

Upper Ball joint has a 16mm shaft with a 38mm base and the lower ball joint has a 19mm shaft and 45mm base. The upper audi boot might stretch to fit but may not last long. I'll keep digging to see what I can find that would be a better fit.

[h2pmr]

probably not much help but i used these many years ago and are still holding up well.
as pictured, i just test fitted a new one to a spare ball joint i have, + new one next to an original for height comparison
it does compress down no problem, and original boot metal securing clips do fit on

just cannot remember where i got them from

cheers
Phil

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[maddog2020]

FYI Roger carries the lower ball joint boot.