e60/e90 rust

[lufbramatt]

Esseesse said:

Just reading about e90 rust chances, and I came across this post...

"BMW does a cathodic dipped primer instaed of galvanizing. The paint doesn't have sacrificial anode properties like the zinc."

Apparently VAG do full galvanising. Is there any truth in this and is it why BMW's seem a bit rust prone?

I think VW went overboard with the rustproofing in the late 80's/early 90's, the cars were galvanised and absolutely full of cavity wax. Mid 90's I think they decided it cost too much and reined it back a bit- you see loads of rusty mk4 passats and mk3 golfs- maybe used cheaper steel as well? From mk4 Golf onwards I think they got it sorted. Galvanising has pros and cons- when you start looking on 4x4 forums lots of people don't like galvanised chassis- it creates nasty fumes when welding, the heat can distort thin metal, box sections have to be vented which can lead to moisture ingress in the future, adds weight etc.

[triggerh4ppy]

Esseesse said:

Just reading about e90 rust chances, and I came across this post...

"BMW does a cathodic dipped primer instaed of galvanizing. The paint doesn't have sacrificial anode properties like the zinc."

Apparently VAG do full galvanising. Is there any truth in this and is it why BMW's seem a bit rust prone?

Do a google search for mk5 golf front arch rust. Its a common issue even up until 2007