Quote:
Originally posted by chick-truck:
1
2) F350 hubs
New super-duty hubs also made by Warn. They use pulse-vacuum technology to engage and disengage. Basically an auto hub that engages instantly and you don't need to back up to disengage. You can also manually engage like regular hub. Pulse vacuum system is integral with entire 4wd system and is not retrofitable



I had these on my old Chevy S-10. But I didn't have the option of using them manually. The only problem I experienced was the vacuum system wasn't all that reliable. All of a sudden you'd have no 4wd and not know why. There's no sound or anything that happens to indicate the system stopped working. I think GM still uses this system. I just wasn't all that thrilled with it.