To powder coat or not, your VW T3 gearbox

[@MrXTinguish]

i just painted mine with aluminium primer and silver wheel paint. 2 years ago and 2winters in Germany an in total 60.000km through Europe and still looks fine powdercoted gets infiltrated at the spots where rocks hit it while driving

[@Gadomaitis]

50% of 2'nd hand car market to Lithuania comes from Germany, personally, I haven't seen rust buckets arriving from Germany, like we do have here in Lithuania, people are choosing to buy 7 years old car from Germany rather same used car from Lithuania, because of the rust. I was wondering, what's the secret, no salt in street during winter, wax after buying it new? Appreciate your answer, I will paint it your way.

[@sim6699]

One T25/T3 had a painted gearbox with the same outcome as yourself. The next T25 I chose not to paint it.
Perhaps the key is using aluminium primer as another commentor suggested

[@Gadomaitis]

Maybe if it started to oxidize, aliuminium needs a special treatment and the key might be that primer, as he commented. I will try to paint it this way