Stub Axel broke
Thread Starter
Three Wheelin'
Joined: May 2001
Posts: 1,620
Likes: 0
From: Plano, TX
Thanks for the exact spec Jeff.
Tony, I didn't feel anything prior to it breaking. I just had a new set of tires mounted for the session and the car felt better than ever. I remember thinking to myself how good it felt. Then all of the sudden, I felt a snap. If you go over to the Racing forum, it looks like Chris C. thinks that you should re-torque new hub bolts after a session because they may unseat. I tell you, I'm checking all of them next time. Now to find the handy torque wrench that handles 339 ft-lbs.
George
Tony, I didn't feel anything prior to it breaking. I just had a new set of tires mounted for the session and the car felt better than ever. I remember thinking to myself how good it felt. Then all of the sudden, I felt a snap. If you go over to the Racing forum, it looks like Chris C. thinks that you should re-torque new hub bolts after a session because they may unseat. I tell you, I'm checking all of them next time. Now to find the handy torque wrench that handles 339 ft-lbs.
George
Race Car
Joined: Mar 2002
Posts: 3,558
Likes: 516
Although not for Type 993, I thought youi might like to see pictures of the axle we make for the GT3 RSR:
1. lightweight, high angularity (unlike, e.g., tripods that respond less favorably to extreme bump and droop) ten ceramic ball CV's for better power delivery;
2. specialty high strength steel (with proprietary processing) components – everything but the dust covers and the boots;
3. aerospace tear/crack resistant boots;
4. enhanced inboard and outboard cooling;
5. machined in integral speed sensors;
6. complete with specialty high strength steel (with proprietary processing) lightweight fasteners (MJ10 x 1.5, heads are 12 point, 11 mm) with provision for safety wiring;
7. are filled with Krytox GPL 217;
8. are fully serviceable inboard and outboard -- both for examination and individual parts replacement;
9. all axle components can be made available on a piece by piece basis so as to enhance efficiency and reduce operating costs; and
10. all axles are serial numbered.
1. lightweight, high angularity (unlike, e.g., tripods that respond less favorably to extreme bump and droop) ten ceramic ball CV's for better power delivery;
2. specialty high strength steel (with proprietary processing) components – everything but the dust covers and the boots;
3. aerospace tear/crack resistant boots;
4. enhanced inboard and outboard cooling;
5. machined in integral speed sensors;
6. complete with specialty high strength steel (with proprietary processing) lightweight fasteners (MJ10 x 1.5, heads are 12 point, 11 mm) with provision for safety wiring;
7. are filled with Krytox GPL 217;
8. are fully serviceable inboard and outboard -- both for examination and individual parts replacement;
9. all axle components can be made available on a piece by piece basis so as to enhance efficiency and reduce operating costs; and
10. all axles are serial numbered.
Cows-4-Rent
Rennlist Member
Rennlist Member
Joined: Jul 2001
Posts: 1,464
Likes: 1
From: Colorado Springs, CO
I had my stub axle go at Road America this year. My thought was that the wheel bearing went first and caused the stub to sheer off. I am not certain if that was the case but it is interesting that you just had your wheel bearing replaced. Is it possible that that was not done correctly or you got a bad bearing to begin with? When mine went I was lucky that I was in the carousel (right hander) and it was the right rear that went.
I had to replace the wheel bearing, hub and stub axle.
I had to replace the wheel bearing, hub and stub axle.
Thread Starter
Three Wheelin'
Joined: May 2001
Posts: 1,620
Likes: 0
From: Plano, TX
Jeff,
I replaced both the driveshaft (which includes the stubaxel) and the wheel bearings, not just the bearings. The bearings went about a month ago and we decided to also replace the driveshaft because it felt a little stiff (cluncky) on the stub axel side.
George
I replaced both the driveshaft (which includes the stubaxel) and the wheel bearings, not just the bearings. The bearings went about a month ago and we decided to also replace the driveshaft because it felt a little stiff (cluncky) on the stub axel side.
George
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Pro
Joined: May 2002
Posts: 570
Likes: 1
From: Las Vegas
One thing we do on the race car I work on is to mark the location of the nut after installation and torque. A simple dab of paint allows you to do a visual.
Glad this did not turn into a major off for you.
Pete
Glad this did not turn into a major off for you.
Pete
Instructor
Joined: Jun 2001
Posts: 125
Likes: 0
From: Auburn, WA
George,
Few years back on my 1987 Carrera had a similar problem. The car was handling funny so I took it in for an alignment. The shop guy said he couldn't align it because the left rear wheel bearing was shot and the wheel was about to fall off. I managed to get it home and noticed the nut was loose. I tightened the nut some and then took it to my Porsche mechanic to look at. He said that sometimes the left rear wheel nut comes loose, but only the left for some unkown reason. He retightened the nut and used Loctite on it too. Never had the problem again.
Was it the left rear that came off on you?
Jack
Few years back on my 1987 Carrera had a similar problem. The car was handling funny so I took it in for an alignment. The shop guy said he couldn't align it because the left rear wheel bearing was shot and the wheel was about to fall off. I managed to get it home and noticed the nut was loose. I tightened the nut some and then took it to my Porsche mechanic to look at. He said that sometimes the left rear wheel nut comes loose, but only the left for some unkown reason. He retightened the nut and used Loctite on it too. Never had the problem again.
Was it the left rear that came off on you?
Jack
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From: yorba linda, ca
Stub axle (one failed, one new) from our spec Altantic car. What kills these is when two cars touch wheels, back of one wheel to the front of another, and runs some serious twisting moments through the shaft section of the stub axle.
Cracks start at the root of the lateral spline, then radiate outward, towards the threads. I feel like 'Grisom' on CSI Vegas sometimes when we tear into a failed part, trying to determine failure mode
Cracks start at the root of the lateral spline, then radiate outward, towards the threads. I feel like 'Grisom' on CSI Vegas sometimes when we tear into a failed part, trying to determine failure mode
Thread Starter
Three Wheelin'
Joined: May 2001
Posts: 1,620
Likes: 0
From: Plano, TX
Damn, you got me Pete. Would it make a difference if it was black?
Chris, I wish I could have found the parts that broke off. The cornerwrokers looked in between sessions but had no luck.
George
Chris, I wish I could have found the parts that broke off. The cornerwrokers looked in between sessions but had no luck.
George
Pro
Joined: May 2002
Posts: 570
Likes: 1
From: Las Vegas
Originally Posted by George A
Damn, you got me Pete. Would it make a difference if it was black?
George
George
Pete