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Does anyone know if the 2003 Z06 was prone to counterfeit or substandard fasteners on the vehicle? My 2004 Z06 was perfect and I raced it for years doing all kinds of service including engine rebuilds. I'm now racing a 2003 Z06 and this thing is a POS! For example, I have sheared off 10.9 bolts on the rear caliper on re-install. I have twisted off the exhaust bolts with nuts frozen onto the studs! Even with heat and break free I have deformed the remaining 5 studs but got the bolts off. Metal material is avulsed from the studs all 5 remaining and they cannot be reused. This reminds me of working on hondas for the 90's where any fastener removed I would just throw away and put new not honda hardware.
Anyone else have this problem or perhaps I got a monday car and everyone was hung over?
Well i doubt GM would short sheet you on something like mic. hardware, the price difference is neglectable. Having said that, there is always a chance that 'China' fasteners were used, but I would ( hopefully like GM ) I'll pay extra for Grade 8 bolts and there is a reason why they are a particular golden in color and once you use them you always remember the exact color from the manufacturer, i always spent a few minutes looking the head stampings over to feel comfortable with them. I think you might have a case of someone else had a hand on this Corvette. Good luck I think once you are able to replace any counterfeit fasteners you stop having things falling off at unappreciated time.
avulsed
pulled or torn away.
"all hairs were avulsed from the root"
I learnt a new word today! 50 years of crossword puzzles and I've never read this before. I'd have probably gone -- incorrectly -- with galled. Nice!
I have a 03 Z06 and have not had issues. Chances are the bolts you’ve had issues with had been over torqued by past mechanics or owner. I doubt it’s a material issue since it’s more than one size fastener.
Of course the exhaust bolts have been heat cycled so many times it’s no surprise on those.
Over torquing is probably the culprit. I bought plenty of GM hardware and haven’t had problems. If you’re talking grade 10.9, they have great tensile strength but are brittle.
You might try easing them out, pulling them both direction until they start to move a little. Also, if you have been using impact wrenches, try using a hand ratchet instead to loosen the bolts.
I think GM says to replace those rear caliper bolts. I never have and change pads every track day, but I always use torque wrench.
Exhaust bolts on a car that old should almost be expected to break! I use brass nuts on all exhaust systems.
I take it you purchased the car used. Big problem is you don't know who worked on it or how they abused it during repairs (over torquing, cross threading, ...).
I think GM says to replace those rear caliper bolts. I never have and change pads every track day, but I always use torque wrench.
Exhaust bolts on a car that old should almost be expected to break! I use brass nuts on all exhaust systems.
Yeah... I'm just a little shocked by how poor my 03 car is when my 04 was like the brick shat house by comparison. I have taken to throwing out hardware on this car and replacing with new like I did in the old days with Hondas. I did not want to wait for exhaust hardware so I cut off the bad parts and welded good parts to make new exhaust studs so I could get running. Wasted 2 hrs!
Well i doubt GM would short sheet you on something like mic. hardware, the price difference is neglectable. Having said that, there is always a chance that 'China' fasteners were used, but I would ( hopefully like GM ) I'll pay extra for Grade 8 bolts and there is a reason why they are a particular golden in color and once you use them you always remember the exact color from the manufacturer, i always spent a few minutes looking the head stampings over to feel comfortable with them. I think you might have a case of someone else had a hand on this Corvette. Good luck I think once you are able to replace any counterfeit fasteners you stop having things falling off at unappreciated time.
Colors on bolts mean little, other than the type anodizing/coating they have. The more accurate way to determine strength are the markings on the heads on S.A.E. fasteners, and numbers on metric fasteners, which denote the grade they are. The more markings, and the higher the number, the stronger the bolt.
Unfortunately, there are lots of counterfit/knockoff parts out there. Some of the packaging is very convincing. It's bad when these parts end up on your car, worse when they end up in your airliner's engine...
I've been working on an '03 and it hasn't had problems like this. Same with an '01 and '00. Only guesses are the car was exposed to salt and/or over torqued.
20 year old car and ugga dugga is a meme for a reason. Some people never use a torque wrench, tighten to when they can't turn it and often with air tools.
Yeah... I'm just a little shocked by how poor my 03 car is when my 04 was like the brick shat house by comparison. I have taken to throwing out hardware on this car and replacing with new like I did in the old days with Hondas. I did not want to wait for exhaust hardware so I cut off the bad parts and welded good parts to make new exhaust studs so I could get running. Wasted 2 hrs!
An SFT 10.9 bolt is a metric hex bolt with a strength grade of 10.9. It is made of medium carbon steel that has been quenched and tempered. This gives it a high tensile strength of 1040 MPa and a yield strength of 940 MPa. It is also corrosion resistant due to its zinc plating.
SFT 10.9 bolts are commonly used in automotive applications and for bolting large and forged parts. They are also used in a variety of other applications where high strength and corrosion resistance are required.
Here are some of the specifications of an SFT 10.9 bolt:
The manifold studs are shitty and then with the heat they eventually rusted making them even worse. I think 4/6 of mine broke and the other 2 were damaged when I took my exhaust off. There are many cases of them breaking off or being damaged.
The other bolts were likely damaged by previous work before you got the car and you finished them off.
Counterfeit or substandard hardware
yup F.S.M. pretty much has you replacing cradle bolts, caliper, shock mount, head bolts.....
