jim-81

So, this past Sunday, I went out to a Corvette/Chevy show at Tim Lally in Cleveland (Warrensville). Pretty good show, but mostly newer cars. On the way home, after I turned on to a side road (after being on the freeway) I got a BANG! and rumble... rumble. Coasted it to the side and got under her. Busted half shaft.

Got 'er home and took a look at it. The actual yoke on the shaft side gave way, the U joint was fine. So I am looking at it, and what I think happened is that possibly the clip came off and the U joint was off center (which accounts for the vibration) and eventually worked its way out. I have had a vibration that I couldn't pin down for a while now. Don't know for sure yet if this was the cause.

Didn't do too much damage, it was limited to the fiberglass compartment behind the passenger (wife wasn't riding in it at the time lol). And the shaft of course. I will be replacing both of them and putting in new U joints. I installed these about a year and half ago.

If you look at the close up of the shaft, you can see an indentation where it looks like the U joint was riding off center for a while.

Anyways, it could have been a LOT worse. I was on a nice quiet side road - after being on the freeway.

Big2Bird

Nothing like a half shaft up your azz to wake you up. Glad your okay.

raydog9379

"Didn't do too much damage, it was limited to the fiberglass compartment behind the passenger (wife wasn't riding in it at the time lol). And the shaft of course. I will be replacing both of them and putting in new U joints. I installed these about a year and half ago."

Replacing the fiberglass compartment and the shaft or the wife and the shaft?

In all seriousness, I'd be curious if it was an installation issue or a parts/manufacturing issue? Or parts compatibility issue (U joint and shaft)? Don't want to repeat the same issue in another year and a half.

jim-81

I don't know, as far as what exactly was the cause. The only clue is the marking on the yoke. It could have been installation, parts or mfg. It was the first time I had done it. The half shafts I got from a forum member. The only thing I can do now is make sure I get them in right. If the vibration goes away that will point to this issue so we will see.

As far as the wife - I think I'll keep her!

Gale Banks 80'

I'm going to say that the U-Joint probably wasn't seated into the Yoke properly. And or the 1/2 shaft had been bent when an old U-Joint was extracted. I have done the same thing. Double checked things before a first drive only to find a U-Joint not seated properly. To replace the Yoke You will need to remove the Dana 44. The Fiberglass repair will be easy when its out.

worship79

Glad you came out okay and damage was limited.

mike11

Were the half shafts balanced? I've broken driveshaft yokes before due to the shaft being out of balance

Wee

It's my understanding that the half-shafts are not balanced....At least not from the factory.

Brian

76strokervette

Sorry for your misfortune. Those look like the 1330 u-joint half shafts.
IF you are interested the driveshaft clamp I made for my car should fit
your stub axles but you would have to upgrade the thread to 5/16.
You can see the part on the 12 bolt thread(it is the first u-joint clamp).
Just an option for any of the batwing guys that want more strength.
Let me know if you are interested.
Dave

jim-81

Probably something like that. I will definitely pay close attention when putting the new ones on. The yoke on the diff is OK, thank god.

Fiberglass repair is coming along nicely.

jim-81

No, these are the 1350's

jim-81

That was my understanding also, that they were too 'small' to really worry about balancing. But who knows, it could have played a part.

76strokervette

I don't know if my 76 half shafts will work for you but if they will their yours for free if you want them. I have test set of 1350 clamps made of 4150 chrome moly that may work for you.The straps are what threw me off. Were they from the stub axle or the driveshaft?

jim-81

I have a set coming from Bair's - should be here today or tomorrow but thanks for the offer! The clamps are from the stub axle and were still attached. So they didn't give out, which also points to the retaining clips failing/missing.

Here's a picture of the stub axle with the U joint and clamps still attached:

sjhanc

If you look closely at the yoke in the 8th picture, the upper left bolt hole is wallowed out from the bolt being loose. For a drive shaft, once the U joint slipped off center, it would only take a few seconds for it to yank the loose bolt out and then destroy that end of the driveshaft.

jim-81

Nope, they were all tight. The U joint was still securely bolted to the axle yoke.




The picture of the U joint still bolted in place is not clear and I have since removed it.

BlackC3vette

Regarding the subject of balancing the shafts, I had mine balanced before I put them back in my 80. I remember asking how far off they were when I picked them up. There was no question that they were off and needed balancing. This is a shop that I've deal with for a couple of decades, good guys, a busy shop.

HoldHard

HH

Doug Kraft

You could put the shaft safety loops -both inner and outer to keep something like this from happening again.

bigredbrad

what is the shaft made out of? some sort of carbon fiber?


bigredbrad