Bent rear under brace from jacking the car at wrong jacking point.
 

I went under my Z today and found 2 dents on the the rear undercar brace (one on each side of the car). A local shop here probably used the brace as jacking points instead of the chassis rails. Should I be worried of the damage? Does this affect the rigidity of the car, or is it purely cosmetic? I also noticed on the right side, the brace touches the gas tank, while on the left these is about 2-3mm of gap in between them.
First two pics below are the right rear and the rest are the left rear.

That brace is definitely useless now. Its whole point to begin with is to be rigid, and it is definitely no longer rigid. How many shops service your Z? I'd go knocking on their door and make them pay for a new one + labor and take it somewhere else to install or just do it yourself.

This is why I'm glad I'm equipped to do all work myself; it seems a general rule that your average "mechanic" has an IQ no higher than 85.

Yah, that's one sad shop whoever did that. :mad:

Most mechanics just don't care about quality as much as quickness. I know several techs at major dealerships. They all get paid per job so the quicker it gets done the more jobs they can do. I would definitely take it back.

I wouldn't sweat this. It's minor and still doing everything it's supposed to do. I'll post a pic of mine some time. About two months after buying my car, I saw that the leading edge of the same brace was folded oven on itself. Looks like someone had taken a spin and bottomed it out. Fact of the matter is it makes no difference...and I track my car plenty.

Thanks for the inputs. The thing is most shops (even the reputable ones) in this country don't admit when they made mistakes. If they do, they'll probably repair the damaged part instead of replacing with a new one. The 370Z is also rare here, so OEM parts are hard to come by. I think I might just have to live with it, or replaced it with an aftermarket braces when they become available. :(

Are we talking about Thailand, or the USA? Because they do the very same thing here in the USA.

get your *** to that shop and demand full replacement of the damaged parts. Your car's suspension is toast.

Well, I had better luck while I was living in L.A. and had my EVO worked on by great shops and mechanics. I can't say the same here in Thailand. Most shops would just rip-off customers with counterfeit or used parts. Mechanics are also poorly trained.

I would have a conversation with the shop manager for sure after this or look for another shop.

so how's that different from 90% of LA shops? :tup: ;) :p

The shop clearly made a mistake and it's worth pursuing. But it's a bit dramatic to say there is major damage here. This is really nothing to worry about.

No it's not a huge deal, but that brace that was put there for chassis rigidity is now useless. It would piss me the hell off if a shop did that to my car. Granted, they could have pinched a brake or fuel line or something worse...

How is it now useless? Yes it's very slightly bent. But it's a metal piece that is still completely intact and bolted in place. It still resists any longitudinal forces placed on it. Frankly, from the pictures it looks like cosmetic damage only. I'd bet my nuts you'd never notice any difference in performance.

:facepalm:

If there were a dent in the Bay Bridge do you think they would allow vehicles to traverse it? Or would it be still "completely intact?"

Just because it's underneath the car does not make it "OK" for it to be bashed up. That piece needs to be replaced. The visual damage doesn't even tell the half of it if they actually placed the entire ~1400 lb rear weight of the car upon that one point.

true, the car could suddenly fold in half. :D

Exactly :rofl2:

It's fine, OP don't worry. If you can get it replaced, then why not, but I wouldn't make a fuss about it...it's not going to change a thing.

:iagree:

Steel doesn't lose its rigidity upon slight bending. It would piss me off too, but it's not useless now! Haha are you guys trying to scare the OP?

:rolleyes:

Captain Melodrama! (I like you buddy, but I have to play devil's advocate here)

All that brace does is counter forces that act along its length. If you think the minor dent in it is going to compromise its ability to withstand those forces, you're crazy! Maybe it's 5% weaker, but that's a realistically insignificant value. The Z performs well, but it's not fighter jet. This kind of minor stuff just isn't worth fretting over. Using the reasoning presented here, I better replace my tie-rods because the surface corrosion on them means they're worthless and will fail suddenly now.

leave it or replace it...The shop that did it cant be held responsible since you left the shop and didn't have proof they weren't bent when you went in..just the truth. Iv been a victim of shop negligence before.

yep, especially watch out at tire shops. this is one of the many reasons why i NEVER take my cars to the tire store. i just bring the wheels in loose. :p

Hate to revive an old thread but whatever. I found a few threads talking about this piece but can't seem to find a part number or even the correct part name for it. Just noticed while putting on my FI exhaust that mine it bent as hell also.

I looked on Courtesy Parts website and searched for, braces, chassis braces and every other term I could think of but no dice. I keep coming up with the GT Spec braces.

Here joo go

STAY ASSY-TUNNEL - 370Z (Z34) 2009+ :: Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com

Thanks Sh0vel!

The damage appears to be mostly cosmetic. The bigger problem is that an idiot has been working on your car. If that's the worst thing that is wrong consider yourself lucky. I'd double check whatever work you had done.

Is it just me or are the jacking points on this car hard to detect? I have heard a lot of horror stories with wrong jack points, scuffed, bent side skirts from supposedly experienced mechanics.

The side points are a little hard to find if you don't actually get down and look underneath the car. A little hard to just "feel". This is because they're recessed down inside the side skirt.

The center points aren't obvious at all if you don't have the FSM to reference.

ROFl... that brace is useless..

not really, just low even at stock height and hard to see.

Plus I never know where to jack the car up when using jack stands, since I can't do it from the jack points. I always **** a brick until I lower down into the stands.

Get a more serious jack, then you can jack from the center points and put the jack stands on the side points.

That's what I do, the car sits on 6 ton stands with rubber boots on the ends that hold the pinch welds. Thing doesn't move, at all, and the bottom of the car is a good 16-18 inches off the ground. Far enough up for me to use a creeper without issue.