Why a Dirve Shaft Hump in Rear Seat of FWD Vibe

[JimHSoars]

Hi all:

I just noticed that my front wheel drive 06 vibe has a drive line hump in the rear seat area floor. I have had other FWD cars and they didn't have this hump. Did GM run out of proper lower body parts or is this on all Vibes?

- Jim

[joatmon]

I don't know about the 09-10's, but probably the same as for the 03-08's, where what seems like a driveshaft hump is really the channel for the exhaust pipe. Having the hump provides space for the exhaust to run in without hanging down below the bottom of the floor pan. The ground clearance on these cars isn't very tall, so if they had a flat floor pan, we'd have lots of genvibers ripping their exhaust systems off on rocks, possums, who knows what else.

It also keeps things from rolling around too much. I once had a dodge caravan, it had a completely flat floor pan. If there was every anything on the floor you couldn't reach while driving, you just had to slam on the brakes, and there it was.

[CharlesinGA]

It adds strength to the overall structure. Also, they are not going to make different stampings for different models like that, if they can save money and make one that fits all.

Charles