gdb069

C8 non-Z51
I have a friend who lives in an apartment that has a hand car wash bay. As you drive into the bay, there is a 6-7" high "speed bump" to keep water in the bay. Her SLK350 has no problem going into the bay, however, the C8 gets about 3/4 the way in, just before rear tires go over the bump, and I hear a terrible clunk from the bottom of the C8. The C8 does not get stuck on anything and I have not looked. Oddly, backing out there is no clunk.

My last oil change I asked the service advisor if they could identify any damage under the car and they said they could not see anything but who knows what was examined. Maybe its just one of the panels underneath so no damage.

. My question is: what is the lowest thing under the C8 at about 3/4 toward the back that is providing that "clunk" ?

Update: to be more specific: lowest point other than tires and wheels

madrob2020

My guess is that it is something in the far back just before the rear wheels. It drags going in because nothing is raising the “impact” point when it reaches the low point. Backing out the tires lift that point & doesn’t drop the point down till past it. 🍻

Red Mist Rulz

Next time I'd stop the car just before the point where clunk occurs, get down on my hands and knees, and have a look-see.

Two vets

Two summers ago l had to make a left hand turn into a restaurant. Traffic was busy so l had to approach the entrance quickly. The sidewalk was much higher than the driveway and l thought "this was going to hurt" I hit the brakes and heard a loud scrape from under the drivers seat. Fealt crappy over dinner because l thought i'd be replacing panels below the car. Fast forward to two days later. Put the car on the hoist to inspect the damage, but there was nothing to see. I had to look over every inch and all l could find was one bolt head covering one inspection panel that had been shaved down a bit. Took a deep breath and realized l got off lucky.

Kevin A Jones

You can't look under there?

LIE2ME

There are two protrusions (one on each side) just in front of the front wheels. They are part of two plastic panels covering the undercarriage. I have scraped them several times. No damage to the mechanics or chassis that I can see, but frustrating to experience...

gdb069

Tonight I tried to look under as I got to the clunk zone but the car is so low that I could not see anything. Tried using a light but still cannot see enough

Front wheels go over OK and I get past the drivers seat almost to where rear wheels will touch the speed bump and ... clunk. My front lift may be reducing scraping in the front. I am starting to think its just some panel bolts. If I am near dealership I may asked them to hoist and take a closer look.

acrace

On my car the lowest point near where you describe are the bolt heads that hold on the center tunnel closeout. I have an open trailer with a beavertail and that is the point that hits when I had the car lowered too much.

gdb069

Thank You. I will take a look or wait until next hoist and avoid the wash bay till then.

Tim0shel

It's the bolts, I'm lowered and had bottomed out on a speed bump at angle and tried to look over everything when I did my oil change up on the quick jacks. I could see some marks on the bolts but obviously they are harder than the speed bump I hit so damage was minimal. I will be ordering a few bolts just in case this happens again which I do pretty good a planning where I am going and what obstacles there will be. I would rather change them out than them to get too bad of shape to get off.

Sounds like if your front is clearing you need to go at an angle or something? My front hits everything, well the area right in front of the wheels.

Undy

The tires...

Vetteman Jack

Very possible that it is bolts holding panels or other parts on the car. As you say, next time the car is on a lift, do a careful inspection of the area of concern.

Red Mist Rulz

I was going to say that, but decided discretion was the better part of valor.

Bburr

Cut a 2' x 3' x 3/4" piece of plywood and lay it down on each side at the appropriate place on the floor.

gdb069

Thanks. My front may be clearing due to front lift activated when entering the apartment complex. Maybe I will try lowering the front. I am slightly happier its just bolts rather than engine/tranny/exhaust/suspension.

dohabandit

Mine are tore up, even with front lift.
One is hanging down and missing 4 screws. I think the chevy dealer screwed up and didn't install the fasteners after checking my leaking front end lift reservoir.