I was driving very slowly on a small airport road when suddenly a "clunk" and no more power to the wheels !!!! Look under the car and nothing obvious. I was having a strange feeling on the clutch pedal and I was able to select all the gears but no reaction on the wheels except sometimes a series a little "clunk" under the car.... OhHHH MY GOD $$$$$$$$ gearbox, differential, clutch, clutch fork!!!!!! A towing came and while he was winching the car to his platform I saw the left hand drive shaft disconnected . Took the car home ($197.00) , jack it immediately and found the shaft was completely off without any damage to anything around and all the bolts were ok
Reconnect everything torque it with my brand new calibrated snap-on torque wrench to 60 ft/pds. What happen??? The repair manual mention 60 foot pounds but I have used my older not calibrated craftman torque wrench to install this shaft over two years ago..... After a test of those two torque wrench I discover a difference of over 10 foot pounds between the two. Is it enough to get those bolts to loosen up by themself. I don't know. I also always put grease on my bolts... Should, in that case, leave it dry???? Anyway my pressure is back to normal, my wallet a bit lighter and my wife is aloud to talk again

 

I doubt that if you torqued to 50 instead of 60 that would make enough difference to really have them all fall out. I would recommend new bolts and some lock-tite if you want to be paranoid.

 

JP happy that everything went well and no big problems!

 

My 2 cents:

- don't use grease because the "fastening torque" results in a clamping force of the bolts DUE to friction on the threads. Using grease you decrease the friction coefficient = not good.
Use a specific product instead.

- A different fastening torque can cause problems, but I don't think 10 ft/pds would, especially on the driveshafts because they are not subjected to high heat like the head studs for example.




It happened to me that my mechanic (on the first and last time he put his hands on my car) fastened the driveshaft bolts without using a calibrated wrench.
Result: two bolts broke on the highway at 90mph, hitting the underside of the car and bouncing over the windshield of the car that followed me....

 

That's a good suggestion Loctite can be useful... I will keep an eye on it and retorqued at every oil change. I was also thinking of drilling bolts heads and install lockwire! Thanks

Thanks Alex. Are you looking for an antique torque wrench?



That's something I was worried about. My luck is it happen at less than 10 km/hr. Thanks for the suggestion.

 

Seeing it was so long ago , I wonder if you might have read the NM scale instead od ft/lbs. Its easy done. Then if you say your torque wrench is 10 ft/lbs out that must be 15 ish nm so you might have only torqued them to about 45 nm ??
Just a thought. I have seen somebody who used to work for me do that.
A good tip for torque wrenches. Wind them back to the minimum setting once you have used it. It reduces the compression on the spring and keeps it in better calibration.
Find you nearest good tool stockist. I use Snap-On who will calibrate your own Torque wrench for you. There are adjusters inside if it is a good make.
All my torque wrenches in the workshop had to be calibrated and sealed.iaw iso 9002.
Frank

 

It will look good next to this

 

Good morning Sunnyside. I also used sealed calibrated torque wrench for my work (transport Canada rules) and this is the one I used to retorque the drive shaft yesterday. The old one, I used normally at home never had any calibration and will never be used again. But mistake is always possible. I'm wondering about the grease I used to install those bolts combine with under torqued.... Anyway I will keep an eye on this more often.... Thanks for the reply!

 

Wow! impressive piece of furniture and I see you are taking good care of it and keep a fire extinguisher nearby

 

yikes... glad it wasn't too serious. it's good to give all the critical connections a check once in a while. on the grease, dunno if it applies to driveshafts but thought the grease allowed bolts to be tightened more accurately because with out it, friction keeps the bolt from tightening completely.

 

You got a good point Madness...

 

My friend had the exact same thing happen on his S4 and it caused some damage to the boot and luckily that was all. I almost had it on my car and I torque with a calibrated torque wrench to exact specs. I just happened to catch it one day while adjusting my shock dampening screw. Three of the screws were un-screwed about a quarter of an inch. I think the inner CV joint grease got into the threads and facilitated the process. One other thing to consider is if the bolts are meant to stretch when torqued? I have heard of people having this type of thing happen when they re-use stretch type bolts. This is because the bolt will no longer stretch without breaking once they have been initially torqued.

 

Another point to consider. I will order a complete set just in case...Thanks for the reply!

 

JP, how were the bolts on the other side? If they were all ok, i'd guess you just forgot to torque them, you might have done only one side.

 

Hello Alex! I hope you had a great day in Tremblant on friday! I have to admit I regret not to be part of it because I was impress with the organisation. So if you don't mind please tell me about the next time. We never know...

About the torque. I remember torquing it. It was done when I did the slave...I had to purchase a metric allen key on a 3/8 drive socket to do the job. That is why I am sure I did apply torque but how much???? Alex did you put 60 foot pounds or more?