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Drive shaft torque specs


zelix
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German specs.

 

 

Gudentite.

 

i think they are M12 bolts. so it would be about 55 ft pounds.

Ok thanks, i set that at 75 yesterday is that ok? or should i lower it down to 55?

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Ok thanks, i set that at 75 yesterday is that ok? or should i lower it down to 55?

 

 

if in fact they are 12mm grade 8.8, (which i think they are) and you torqued them to 75, they now need to be thrown away because you are just about at yeild of the bolt. and have over torqued them. (which means you have stretched them beyond safe use)

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ok, lets look at it this way.

 

56 ft/lbs is 80% of proof load. (standard engineering value)

so, proof load (safe operating range) is 67.2 ft/lbs.

You over toruqed them by 11%.

 

will it fail.. maybe not.. but do you really want to take that chance?

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German specs.

 

 

Gudentite.

 

I normally spell it "gutentite" with a T... Not that I should talk about peoples spelling.

 

But yea, my FSM sais 58-65 ft-lb for the rear shaf and 29-33 ft-lb on the front shaft (at both the transfer case and the differential)

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German specs.

 

 

Gudentite.

 

i think they are M12 bolts. so it would be about 55 ft pounds.

 

I normally spell it "gutentite" with a T... Not that I should talk about peoples spelling.

 

But yea, my FSM sais 58-65 ft-lb for the rear shaf and 29-33 ft-lb on the front shaft (at both the transfer case and the differential)

There you have it. Correct spelling and correct values... ;)

 

Damn good guess 87p.

 

B

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Alright thanks guys, 75 isn't that much more then 65 i think. I asked my dad and he said dont worry about it. I will ask my auto teacher what his best suggestion is, otherwise i dont think i will be victim to any catastrophic failure.

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I would guess that most torques give you the wrong tension by more than 11% anyway...

 

 

plus or minus 5% actually, so, its still too much.. just saying

 

you may be fine for years to come... but you might not..

 

I only tighten my u joinst with a wrench.. if i can't push on it with a WRENCH,, its tight.

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I broke a Pathfinder drive shaft bolt once by over-tightening it - not by much either. Pissed me off.

 

It's really not something to over tighten and weaken, considering the rotating mass, vibration, and the load put on them when accelerating or downshifting.

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Alright thanks guys, 75 isn't that much more then 65 i think. I asked my dad and he said dont worry about it. I will ask my auto teacher what his best suggestion is, otherwise i dont think i will be victim to any catastrophic failure.

 

be safe, not lazy. theres no price on your life!

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Alright thanks guys, 75 isn't that much more then 65 i think. I asked my dad and he said dont worry about it. I will ask my auto teacher what his best suggestion is, otherwise i dont think i will be victim to any catastrophic failure.

 

 

you ever had a drive shaft come apart at 65mph?

 

google it.

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I don't mean to be rude Zelix, but if you choose to go the lazy route with this and hope it'll be fine - you're an idiot. If you don't want to take the advise from the folks on this board, who do know what they are talking about, and then state you're going to ask other sources, then why even bother posting a thread asking about it in the first place?

 

Go to the junk yard or hardware store and replace the four bolts, four lock washers, and four nuts. Then don't over tighten them. It's cheap insurance.

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I don't mean to be rude Zelix, but if you choose to go the lazy route with this and hope it'll be fine - you're an idiot. If you don't want to take the advise from the folks on this board, who do know what they are talking about, and then state you're going to ask other sources, then why even bother posting a thread asking about it in the first place?

 

Go to the junk yard or hardware store and replace the four bolts, four lock washers, and four nuts. Then don't over tighten them. It's cheap insurance.

 

 

really, for the whole 5 dollars it will cost you.

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plus or minus 5% actually, so, its still too much.. just saying

 

you may be fine for years to come... but you might not..

 

I only tighten my u joinst with a wrench.. if i can't push on it with a WRENCH,, its tight.

 

Not that I'm supporting improper assembly procedures at all, but, you really think that the change in surface finish from new to old and rusty, plus any error in the torque wrench (when was it last calibrated etc.), is only going to be 5%? My impression is that torque is really not a very good way to get to a specified tension, but it's really the only thing convenient, so we use it. There are all kinds of more advanced systems out there (indicating washers etc.) for critical applications... they exist due to this problem, right?

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Not that I'm supporting improper assembly procedures at all, but, you really think that the change in surface finish from new to old and rusty, plus any error in the torque wrench (when was it last calibrated etc.), is only going to be 5%? My impression is that torque is really not a very good way to get to a specified tension, but it's really the only thing convenient, so we use it. There are all kinds of more advanced systems out there (indicating washers etc.) for critical applications... they exist due to this problem, right?

 

 

Ok, if you REALLY want to get into detail

ALL torque values are supposed to be wiht new bolts and light oil on the threads.

 

You are NEVER supposed to torque a bolt more than once.

Lock washers are garbage, cause they dialate over use, and the bolt becomes loose, leading to fatigue failure.

 

 

You have to remember, if its yours, do what you want, but if you are making a recomondation to somebody, you better make sure your right.

will it fail.. can't say

but for 5 bucks? come on.. change them.

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Tensioning is the best way to go, but impractical, we used stud tensioners for anyting longer than 300mm long and over M30 diamter.

 

the longer the bolt the more deflection you get during torque, leading to more inconsistant torque values.

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I don't mean to be rude Zelix, but if you choose to go the lazy route with this and hope it'll be fine - you're an idiot. If you don't want to take the advise from the folks on this board, who do know what they are talking about, and then state you're going to ask other sources, then why even bother posting a thread asking about it in the first place?

 

Go to the junk yard or hardware store and replace the four bolts, four lock washers, and four nuts. Then don't over tighten them. It's cheap insurance.

Ok then, what do i need to ask for at Napa or wherever i decide to go? for the bolts nuts and washers?

The truck is not at my house.

Edited by zelix
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