How tight is tight?

[racingundertaker]

I have just replaced the rear end cover on my 73 Vette....due to one of the ears cracking off (among other problems). I purchased a new cover from Muskegon Brake....which was delivered almost next day.....and went on with no problem. Thanks Muskegon Brake! Anyhow, I replaced everything in the tail and set the car down. Now my question is........how tight do I get the four bolts that hold the spring to the underside of the cover? I know the tech manual says 55 to 60 ft.lbs. Once I got the car on the ground and got the suspension settled.....the front two bolts tightened up, but the rear ones that go into the ears don't seem that tight. I tightened them up so the lock washers flattened.....but do not want to overtighten them for obvious reasons. Is it alright to tighten them snuggly so the lock washers flatten out......or do I have to really torque them? It was a lot of work (plus lost road time) replacing the cover....and I don't want to do something boneheaded like break an ear off again. Thanks..............

 

[Dons97]

whew! When I first saw the title of this thread, I thought we were going to get some pretty raunchy replies!

Boy, I'm glad we're all being adults here.

 

[Vettehead Mikey]

Well, if the GM manual says that the bolts should be 55-60, why would you not torque them that value?

 

[Zohhh6]

Well, if the GM manual says that the bolts should be 55-60, why would you not torque them that value?

I agree, stick with the factory torque values.

 

[Zohhh6]

Well, if the GM manual says that the bolts should be 55-60, why would you not torque them that value?

I agree, stick with the factory torque values.

 

[wishuwerehere82]

As I actually paid attention in my first lecture in MET101, here is what I learned.

The torque numbers are not something that are derived out of ouija board. The Society of Automotive Engineers have a handbook that lists the torque specs. for all known bolts and nuts. The torque spec. reflects the maximum load that a given size thread will exert on a surface when torqued to that number without stressing the bolt +- 5/1 safety factor.

The torque is based on the material of the bolt, the root diameter of the bolt, and the number of threads/inch. The maximum holding torque ensures:
1) the maximum force is exerted on the surface being bolted.
2) That the maximum shear force on the bolt is not exceded. And
3) The the holding force doesn't allow the bolt to back out of its threads.

So, the torque spec. is not so much for the application, as it is for the size bolt you are using.

 

[ON 7TH]

Loosen the bolts & re-tork in a X pattern. set the wrench at 40 lbs,then increase by 10 lbs until ya hit 60

 

[gmjunkie]

I agree, stick with the factory torque values.

I 2nd. that!! gmjunkie!!

 

[gmjunkie]

I agree, stick with the factory torque values.

I 4th.That!! gmjunkie!!