When they are working properly they kinda go down slowly, maybe 1 to 2 seconds for the whole process. And even then not evenly, one may close faster than the other.

Bill

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Bill

Backyard Shadetree Mechanic, 30 years running.

1987 300TD
1988 300E (sold, sniff)
1999 S320
1981 Volkswagen Rabbit Truck (Diesel)
2001 Ford Expedition
1988 Suzuki Samurai
On my list to buy: R129, for me, and a R107 for my wife.