Disconnecting secondaries

A g20 that gets 20? ????? You better get a chain and padlock and lock down the hood!!

LOL.......I drove a few 1/2 ton cargo vans in the 70s and 10/12 city and 14/15 highway was more the norm. Did someone slip a Auto O/D in there at some point? Maybe a liter/km thing...lol. j/k

That's great mileage Mike. Don't think i can offer much to advance that number.