I was wondering...If a person should happen to use an extension on a torque wrench, would that alter the torque value of the torque wrench setting?

 

no....unless your referring to a handle extension, then yes, but an extension that goes from the head of the wrench to socket..... no.

HERE is a link on what ctuially changes TQ values

Even using adapters to change socket sizes from 1/2" down to 3/8" doesnt change anything.

 

Yes, it can change the values, but very miniscule.... not worth worrying about. It is impossible to keep perfect right angles with extensions, so values do change.

 

Yes, the extension can twist reducing torque applied to the fastener, as stated before this is usually very minor. Avoid using extensions if possible and if you must use a good quality name brand extension (snap-on, mac etc.) I have a set of impact extensions I use if I'm torquing. I'm most cases the longer the extension the more possibility of torque loss. Use the shortest extension possible.

 

I'm not going to get into a huge Physice debate, but the amount of "twist" in the extension is irelevant while in motion. It only applies when you stop and go. Once you are moving, it doesn't matter. It's static vs kinetic at that point.
Also, the amount of energy lost in the extension while it's twisting is so fractional for auto's it's not even worth mentioning. I'm taking about in/lbs of loss when your at say...80ft/lbs. You really think that will matter torquing something down at 78ft/lbs vs 80ft/lbs with a severly bad twisting cheap *** extension? No! But again, the twist doesnt even come into play unless you stop just prior to the torque wrench clicking.
If you really go slow and try, you can always turn the bolts more after the wrench has clicked.

Not to mention, with the style of torque wrenches out there, twist dial with another twist to lock the torque value in place.....It's MUCH easier to alter torque numbers because the accuracy is crap on those. i use one and I bet 3/4 of the other members use one. Even those Digital ones are only +/-5% accuracy. at 80ft/lbs you could actually be torquing the bolt at either 76ft/lbs or 84ft/lbs.

There's much more to worry about than adding socket extensions.

For handle extensions, this is a differeent story. Use C=D[A/(A+B)]
C=torque setting
D=Torque desired
A=wrench length
B=extension length

 

You are correct, in most scenarios concerning light automotive work there is nothing to worry about.
At work we torque the lug nuts on our trucks to 550 ft/lbs I've seen first hand where using a cheap quality light duty socket extension will apply up to 50 ft/lbs less to the fastener when the wrench clicks.
Also the twist while in motion does increase as the torque increases, again I'm talking about dealing with several hundred ft/lbs torque here, most ppl need not worry about it.

 

Whats the proper torque setting for the truck?

 

That depends what your torquing? valve cover, intake, header studs???...lol

I'm gonna go out on a limb here and guess you are referring to the wheels? 95ft/lbs for 1500's and 135ft/lbs for 2500's

Nobody metioned anything about a specific truck part to torque, that's why i had a little fun with ya. ;-)

 

Hahah my fault. I thought he was talking about tires. But yes, I was referring to tires. 95ft/lbs it is. Thanks!!

 

Thought this sounded different than what I read in my '10 owners manual, so I looked it up: