Dumb Question Re Hump For Drive Shaft, Or... ?

Jul 28, 2010 11 Replies

Hi,



Have a 2009 Buick LaCrosse. Fairly typical front wheel drive, I would think.



Question: Never thought about the hump/tunnel running between the front and rear seats.



If the car is front wheel drive, and presumably the power goes (only) to the front wheels, what is the tunnel for ?



It's not like in the "old-days" where the tunnel hid the shaft going to the rear wheels to power them. Right ?



So, what's it for ?



Thanks, Bob


There are lots of other things running in the 'tunnel'; wiring, fuel lines, brake lines and the like.

Besides, I think the LaCrosse is based on a European design that has an AWD option. Not sure, but I think I read that somewhere.

Also, the 'hump' adds to structural rigidity. Even the original and subsequent VWs had a hump down the middle, albeit very small.

plus you don't have to worry about crap that's on the passenger floor rolling to your side like Corvairs did. It does look cool though with a big open floor up front.

You "Have" the car? And you don't want to look underneath? Cut the carpet with a utility knife, and fold it back. Then use a metal hole- saw bit (perhaps 3/4") in a drill to make a hole. If you can't see anything, make another hole in a different location. Chances are you won't damage anything when drilling, but take care.

~~ Nehmo

The hump does add some structual strength to the car.And, or whatever else might be hiding in there. cuhulin

Also sometimes used to tuck up cables and tubing... my old 914 had a vestigial hump, was used to route fuel line, brake line, throttle and heater control cables.

nate

N8N wrote in news: snipped-for-privacy@g19g2000yqc.googlegroups.com:

It's also a handy place for the shift linkage, for those cars with floor- mount shift levers.

And for FWD cars, the exhaust is often partially recessed into the tunnel, especially bulky items like resonators and cats.

snipped-for-privacy@g19g2000yqc.googlegroups.com:

yes, I forgot about that, the rod for the shifter ran through the tunnel as well.

nate

Is that like a vestigal tail? ;)

I loved my Corvair, except for it only having 80hp. Fantastic traction.

Arrrrgh. By the time I got mine (12 years on) it had been not very well taken care of, and while it was a cool car I got tired of mopping up oil in the driveway...I had the "base" model with a 3 speed manual. I had to tell a passenger in the back seat, Don't put your feet on the 'floor' or you'll be doing a Fred Flintstone!...

My uncle had a '69, brand new, and that was a fun little car.

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