I'm trying to find the minimum tensile strength of the Corvette wheel studs .If I'm not mistaken the Standard wheel stud has not been changed since 1984 and is common to a lot of GM products.
Don't know the answer but why would you need to know that if I may ask?
__________________
1967 Marlboro Maroon 4spd Coupe 1973 Dark Blue 4spd Coupe w/air, original 25,000 miles 1999 Black C-5 Hatchback Coupe 6spd LS1 1934 Ford 3 Window Coupe eng. code "ZZZ" 350-345hp Chevy Powered! 1970 Black on Black Monte Carlo(FOR SALE)Asking $18k
I had three that broke about a year ago .Dealer claimed I over torqued and the studs we're stretched.Keep in mind I'm old and have been torquing wheels for 30 yrs .As a mater of fact I've torqued a few at Bowling Green .The torque wrench was calibrated by Mountain Machine when I first bought it .The wrench is only used on my Corvettes
The dealer wanted to replace all of them under warranty but then said it was my fault and it would cost $1800 .
Anyway I found a place that will test the tensile strength of the old studs but I need the original Min.tensile strength .
Side note, I changed all the studs for about $60 and about 2 1/2 hours .
08 was when GM was not paying vendors and they bought a lot of junk and I think I can prove it .
Thats the short story.The long version includes the service manger getting a wedgie
Call me a fool but in my 43 years of driving I never used a torgue wrench on any wheels on any of my cars, vans or trucks including the C5. Still tighten the nuts on my vehicles that have mag wheels with a large 4 way lug wrench. On my vehicles with steel wheels I use one of my air powered impact wrenchs and never broke a stud using them knock on wood.
__________________
1967 Marlboro Maroon 4spd Coupe 1973 Dark Blue 4spd Coupe w/air, original 25,000 miles 1999 Black C-5 Hatchback Coupe 6spd LS1 1934 Ford 3 Window Coupe eng. code "ZZZ" 350-345hp Chevy Powered! 1970 Black on Black Monte Carlo(FOR SALE)Asking $18k
As a rule of thumb with alloy wheels I torque them at 80 foot pounds. Most use impact wrenches and go 100+ foot pounds and that is why studs get broken.
The recommended torque for C5 & C6 according to GM is 100 lbs .My wifes Ford Escape it's 120 .
I kinda am with you Fred ,I never torqued a lug nut for my first 50 years .Then some young punk kid said how do you know your not over torquing and I didn't have a smart azz answer for him .
I have found that even the best new torque wrench needs to be checked for calibration .
The recommended torque for C5 & C6 according to GM is 100 lbs .My wifes Ford Escape it's 120 .
I kinda am with you Fred ,I never torqued a lug nut for my first 50 years .Then some young punk kid said how do you know your not over torquing and I didn't have a smart azz answer for him .
I have found that even the best new torque wrench needs to be checked for calibration .
The 100 and 120 specs are fine and yes, you will see occasional studs break. Shops have to over torque for liability reasons. AND, if a stud breaks, it's your problem, not theirs.
I noticed two wheel studs broken off after a 500 mile road trip ,they we're both on the right front next to each other.Ya can't get much worse .Thats when I loaded the car and took it to the dealer .They found 5 others on different wheels .I think they should have saved a sample and sent it to GM .
I did find from a fellow who has access to the GM minimum spec .A fellow Corvette owner runs the Maine Technology test lab and will test the original as well as the replacements I used .I guess that should give a clue --let ya know Tues .
I never broke a stud and I never had a wheel come off or loosen up and as I said Mag Wheels 4 way Lug Wrench by feel. Everything else (Steel) my air impact gun where I also have a good feel for that if I have to take them off by hand they are never at the point where I can't get them loose with a 4 way lug wrench on the road.
__________________
1967 Marlboro Maroon 4spd Coupe 1973 Dark Blue 4spd Coupe w/air, original 25,000 miles 1999 Black C-5 Hatchback Coupe 6spd LS1 1934 Ford 3 Window Coupe eng. code "ZZZ" 350-345hp Chevy Powered! 1970 Black on Black Monte Carlo(FOR SALE)Asking $18k
Stud size has much to do with torque value. I can't imagine your Corvette stud size is bigger than a 2004 Silverado. I torque my 24" wheels at 75-85 and never had a problem. The truck is a 2004 and I've had it since new. My 65 corvette has 17" wheels and I torque them at 65-75 as the studs are smaller. I can't think of a reason your studs are breaking unless they were weak to start with or cross threaded when too much torque was applied. Over torquing is not that uncommon. When you have to take a large breaker bar to get a lug off. If it was too tight the friction can twist the stud and then break it.
Test results :acceptable tensile strength as a bare minimum 165,000 .Normal quality range 170,000-178,000 according to GM quality control .
The lab tested two studs that we're not installed on the car but we're from the box I got at the local auto parts store .one tested at 169,800 the other 172,100
Three studs that we're original we're tested one was 176,000 one was 87,200 and the third was 91,700
The results are sent to Maine DOT and they notify GM directly of the results .test method etc .I was not there for the testing ,I only received a phone call .All numbers we're rounded off .
The results doesn't surprise me as GM was buying from any vendor that would sell to them in 08 .
By the way I love my new Michelin tires .Quite ,softer ride .
WOW...2 of the studs were about half of the strength they should have been. That's horrible!
But I like my Michelin's
Ya know 100 lbs of torque isn't a lot as far as physical pressure .The Torque wrench clicks fairly easy even at my age .
100 is what all the tire stores use. My 65 corvette wheel nuts are specified at 60 foot pounds. I run 17" alloy so I go about 15-20 more. It just depends on the size of the stud. And as you experienced, strength of the stud.
Michelin tires are great. Did you get the run-flats?
WOW...2 of the studs were about half of the strength they should have been. That's horrible!
But I like my Michelin's
Ya know 100 lbs of torque isn't a lot as far as physical pressure .The Torque wrench clicks fairly easy even at my age .
100 is what all the tire stores use. My 65 corvette wheel nuts are specified at 60 foot pounds. I run 17" alloy so I go about 15-20 more. It just depends on the size of the stud. And as you experienced, strength of the stud.
Michelin tires are great. Did you get the run-flats?
Run flat and all season .Can't wait for a 24 inch snow storm on my way to Florida next winter.
I had a meeting with Dot today on another subject at the end of that meeting I asked about my wheel studs .The fellow said he wasn't handling stuff like that ,it was someone Else's dept ---Didn't see that comin'
BUT he said he use to and this is what happens in Maine .Within 90 days they send the results in what is called a concern report .Then GM has 90 days to respond unless their attorney requests a 10 year extension .What GM or Ford will usually do is a spot recall on a car before and after mine was manufactured.They also will check for other complaints . Then who knows
Wonder how many others had or have this issue with wheel studs? No way to check visually. And how would you recall unless you did a 100% recall and replaced all the studs for all the vehicles during the period they were available from the vendor? It is a safety issue if they are prone to break while driving but if not, there should be a bulletin out for free replacement if they do break when lug nuts are removed or installed. I definitely would talk to someone at Chevrolet.
Ken are you kidding me? Chevrolet never even got the fix right on the C5 Steering lock problem as their fix did not fix the problem. Now they don't want to know anything. Luckily someone came out with a C5 column lock bypass that sells for around $50. I ended up buying one for my C5 that I purchased last August. Haven't installed it as of yet. Had a GM dealer run my C5 Vin number and it came back that the car was in for the Column Lock fix at a GM dealer. Not trusting GM like others I bought the bypass. Just got to find the time to install it myself. Really don't want to be stranded especially far away from home.
__________________
1967 Marlboro Maroon 4spd Coupe 1973 Dark Blue 4spd Coupe w/air, original 25,000 miles 1999 Black C-5 Hatchback Coupe 6spd LS1 1934 Ford 3 Window Coupe eng. code "ZZZ" 350-345hp Chevy Powered! 1970 Black on Black Monte Carlo(FOR SALE)Asking $18k
Ken are you kidding me? Chevrolet never even got the fix right on the C5 Steering lock problem as their fix did not fix the problem. Now they don't want to know anything. Luckily someone came out with a C5 column lock bypass that sells for around $50. I ended up buying one for my C5 that I purchased last August. Haven't installed it as of yet. Had a GM dealer run my C5 Vin number and it came back that the car was in for the Column Lock fix at a GM dealer. Not trusting GM like others I bought the bypass. Just got to find the time to install it myself. Really don't want to be stranded especially far away from home.
When I unloaded my C5 in January of 03 the first things installed ,column lock bypass and caggs bypass .
The column lock issue had a recall on top of a recall and is still debated to this day .Also it might be noted that the C6 can have the same issue if the battery has a weak charge.
