Excelerate

I had to swap in a new CV axle thanks to a lead-footed friend who managed to explode the previous one. However, unlike the earlier replacement halfshaft, this new one is not content to stay in place, and the bolts are constantly backing out. Normally I've just been going under the car, torquing all of them back to 30 ft-lbs, and continuing on with my life. However, as it is snowing like hell outside and I MUST fix this before next week when I move the car to it's winter home, I figured I would check here to see if anyone knows why they would keep backing out despite being properly torqued.

Attached is a picture of what I have to deal with whilst fixing this annoying problem. Plus, the sooner I get this fixed, the more time I will have to d̶r̶i̶f̶t̶ play in the snow!

elzergone

Uhg, that has happened several times to me before, and both at very inconvenient times.

What I finally did was locktite them in place, and that seemed to hold, but I havn't been driving that car for a while.

Or, a rennlister sells some pretty sweet looking locking CV bolts: http://garage.ideola.com/ Second thing down on the front page.

mikemyers924s

Had a similar problem that actually left me stranded for a while. I've considered drilling a hole in each bolt and threading a small (but strong) wire through each once they are in place. That would keep them from turning. This would be a pretty involved process though... I replaced with the bolts with higher grade ones from fastenal and haven't had a problem since. I do keep a close eye on them though.

MichaelK

http://garage.ideola.com/prod-Stage8...ml#924-944-968

I think this kit resolves that specific problem. I think it is just one of those problems that is unavoidable on some of these cars.

aj986s

By any chance have these been swapped out with bolts that are not allen or triple-square bolts? I ask because I think there's a significant torque spec difference if a bolt is turned from its center versus its perimiter.

tifosiman

I've never had one back out, but I also use brand new bolts when I replace one.

If you re-used the old bolts that held the prior CV on, that's probably your main culprit.

Excelerate

These are factory triple-square bolts, the replacement didn't come with new ones



That could be it, but the other side (which was done at the same time to be safe) hasn't been giving me grief and it also has reused bolts... Oh well. One thing I learned from these cars is that nothing will ever be predictable except timing belt failures every 15,001 miles and that if you hear a noise, it's going to cost you some money

aj986s

X2 that old bolts might have stretched once too often. New bolts is best/safest, but even that isn't foolproof.

There's two other things I could suggest.

1) Make sure the mating surfaces are clean of any debris. Anthing that may cause the surfaces to not be flush, might allow enough vibration/play to allow the bolts to loosen.

2) Insure that the threads where the bolts go into are not contaminated with grease. Grease on the threads can sometimes allow the bolt to more easily loosen later.

onspeed

are the bolts supposed to be TTY?

yellowline

Probably. They are one-time-use.

Arominus

I did those on my car, however i will say they are also vulnerable to striping as well. The groove for the lock makes the top section of the bolt very very strip-able. That said they haven't backed out.

944Ross

If the car is operated with them at all loose, it's likely the threads on both the bolts and the female are damaged (loose) permanently. Without clamping force, the bolts will be in shear and bending over.

Gages 944

Yep you need to put new ones in. I had to take mine off and when I put it all back together they kept backing out so I replaced the bolts and all better. The reason is is because they bolts get stretched out so to say.