Chevy Driveshaft

[bigmarc66]

Hey guys, I was replacing my 87 K20 front driveshaft this weekend. I connected the back 4 bolts to the gearcase, then began installing the shaft to the front gearcase with the u-joint retainers. I dont know how or why, but the 2 out of the 4 bolts snapped while torqueing them down to the front gearcase. So now my only plan is to drill out the bolts and put new bolts with nuts instead of the threaded bolts into the fitting. Has this happened to anyone before? Also one of the end caps fell off the u-joint. Is it okay to just pop it back on or will it continue to pop off, thus the need for a new u-joint in the front. Thanks

 

[Windykid]

Re: Chevy Driveshaft

What did you torque them to.

 

[qaztwo]

Re: Chevy Driveshaft

Yeah how tight did you get them. How far down did they snap?

 

[bigmarc66]

Re: Chevy Driveshaft

The bolts were not even all the way seated when they snapped. Probably little shy of 1/4 inch still remaining until the retainer would be tight. Thats what made it weird to me.

 

[Windykid]

Re: Chevy Driveshaft

The bolts were not even all the way seated when they snapped. Probably little shy of 1/4 inch still remaining until the retainer would be tight. Thats what made it weird to me.

What torque were you trying to get to?

were the treads buggered up??

Remove stud/bolts and run a tap down the treads, oil and install new ones.

 

[qaztwo]

Re: Chevy Driveshaft

If you can not get a bolt extractor on it would try a left hand drill bit and see if that removes the broken bolt. then run a tap down it as was mentioned.
good luck.

 

[bigmarc66]

Re: Chevy Driveshaft

The threads were definetly gummed up. The problem was that the shaft and the bolts were out of the truck for over a year. In that time I think that moisture and junk built up inside and rusted the threads.
You guys talk about re-tapping it which is fine, but can't I just drill them out and put bolts through the new drilled holes. On the front gearcase where the driveshaft connects and the 4 bolts for the u-joint retainers are, the threads went all the way through and I can get a nut on the other side. If you look at the link you can see what I am talking about. It is not the exact same but similar in theory.
http://offroadrepublic.com/fj40/chapter4/front_driveshaft_mounted.jpg

 

[qaztwo]

Re: Chevy Driveshaft

I would think it would be ok. Iwould still try a reverse drill bit first, I've had good luck with the bit being able to remove broken bolts by it self. Might try chevytalk.com. normally good info.

 

[Bondo]

Re: Chevy Driveshaft

Ayuh,......

You can Cob it together Any way you'd like,..... It's Your truck......

Personally,.....
I'd do it Right......
Clean out the threads,+ get the Right Bolts......

The threads were definetly gummed up. The problem was that the shaft and the bolts were out of the truck for over a year. In that time I think that moisture and junk built up inside and rusted the threads.

But,...... It sounds like You Don't like doing things That Way........

 

[dolluper]

Re: Chevy Driveshaft

ROTFLMAO at Bondo....agreed the right way or some hacked up way ....TOO MUCH

 

[bigmarc66]

Re: Chevy Driveshaft

But,...... It sounds like You Don't like doing things That Way........

I was given the truck from my grandfather. He had initially begun to do the shaft, but he lost track and the truck sat. Instead of categorizing me as someone who does not "like to do things the correct way" why don't give me knowledgeable advice instead of your ignorant comments. Your post added no new insight Bondo, so thank you for wasting my time.

 

[Windykid]

Re: Chevy Driveshaft

I would keep it original in order to keep the drive shaft balance correct. Plus you would be using the correct grade bolt.

 

[Windykid]

Re: Chevy Driveshaft

By changing to nut and bolts you could possibly change the drive line Phaze or balance, in return give you a bad driveline vibration.

 

[island boy]

Re: Chevy Driveshaft

If you were going to drill the old broken bolts out and replace them with new bolts and nuts try to take the other two out on the other side as well. Drill them and put new bolts and nuts in as well this would also balance the shaft by having even weight on both sides. I had to do that exact same thing to one of my trucks one time at a mud run, and it is still together today 2 years later, and many more mud pits.

 

[Caveman Charlie]

Re: Chevy Driveshaft

I'd see if you can get the old ones out first. Got nothing to lose. If you can then run a tap down the holes and replace with the proper bolts. If you can't then do what island boy says.

 

[bigmarc66]

Re: Chevy Driveshaft

Thanks for the advice guys, I picked up a set of left handed drill bits today. I plan to extract the bolts and then run a 5/16x24 tap down the holes. That seemed to be what the bolts matched up to, this will fix any rusted threads and ensure a safe second process. Thanks for the help guys.

 

[Bondo]

Re: Chevy Driveshaft

Instead of categorizing me as someone who does not "like to do things the correct way" why don't give me knowledgeable advice instead of your ignorant comments. Your post added no new insight Bondo, so thank you for wasting my time.

Ayuh,....... I'm Sorry Mark,..... If you don't particularly care for Brutal Honesty,.....
I'll refrain from commenting on any posts by yourself,....... Ever Again......
I call it the way I see it,.....

The threads were definetly gummed up. The problem was that the shaft and the bolts were out of the truck for over a year. In that time I think that moisture and junk built up inside and rusted the threads

If you'd have STOPPED right there,+ Done what you're about to do Now,......

You Wouldn't be doing This,.......

Why is there never enough time to do it right the first time,
But always enough time to do it again?

A 5/16" bolt is Tight at 25ft.lbs...... It takes alittle more than twice that to Twist 1 Off......
With you Knowing the threads were All Boogered Up,+ you did Nothing about it but just Cram the bolt into the Mess,.....
And Then, Torque it to Failure,..??..??

I can now tell you that you should be looking for a New Yoke,......
Your lefthanded drill bit will probably do little or Nothing to get the broken pieces Out, as they're firmly planted into the Boogered Up threads.......

Your Best Chance at saving the Yoke is to pull it off, Drill all the way thru the broken pieces,....
Heat the ears with the broken bolts in it,+ Quench it with Cold Water,.....
Then try to remove the broken pieces with plenty of penetrating oil....
Otherwise,......
Run over to your local Parts House,+ Buy a New Yoke,......
It shouldn't set you back more than $30./ $50.......

Good Day,+ Good Bye.........

 

[Bondo]

Re: Chevy Driveshaft

Ayuh,.... As per your PM,....

Don't forget to Replace the Seal if, or when you pull the Yoke.........

 

[island boy]

Re: Chevy Driveshaft

So did you ever get the bolts out and the thing back together???