Lugnut torque spec

1969 service manual says 65 ft lbs. yes it’s true, it’s not 100
 
Be careful if you have reverse threads on the drivers side.
 
As mentioned, in stock form, your car should have left hand studs on the drivers side. However, many cars have had lugs replaced by now to right hand thread.

Left hand lugs are stamped...look for an "L" to be sure.

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Most of the older "steel wheel cars" had lug niut torques in the 65lbs-ft range, either rh or lh threads Be sure to first seat the lug nuts in their recesses to snug them up and center things. Then go about 10 lbs-ft, in the recommended torque pattern until the desired torque is reached.
 
You guys were taught wrong. You're suppose to tighten them as tight as you can, when they strip, back off 1/4 turn.:D
 
Not unlike the torque procedures for some modern engine head bolts and such, Torque to "a value", then add 30 degrees of rotation past that. Not unlike the old shadetree method of "as tight as you can, and then another 1/3 turn for good measure" . . . in an age when a torque wrench was an exotic tool advertised in car magazines.

Of course, the newer torque-angle bolts are a special metal to tolerate these things, not supposed to be re-useable, only one use and replace them.

CBODY67
 
Not unlike the torque procedures for some modern engine head bolts and such, Torque to "a value", then add 30 degrees of rotation past that. Not unlike the old shadetree method of "as tight as you can, and then another 1/3 turn for good measure" . . . in an age when a torque wrench was an exotic tool advertised in car magazines.

Of course, the newer torque-angle bolts are a special metal to tolerate these things, not supposed to be re-useable, only one use and replace them.

CBODY67
Porsche and I suspect other German manufacturers have used the ‘rotation angle’ method for some time.
 
Porsche and I suspect other German manufacturers have used the ‘rotation angle’ method for some time.

GM started to use it on the 2.5L 4 cyls in the 1990s, on head bolts. When I realized what was going on, couldn't halp but laugh a bit, knowing how things might go "on the farm" on implelemt wheel lug nuts.

The torqie angle bolt use is pretty much universal now on GM products, even flywheel to crank bolts. I suspect that more get re-used than should be, by observation of how many dealers mght stock some of those flywheel bolts. These bolts seem to have a higher tensile strength, due to the sound when they are dropped, from the prior-normal bolts, by observation. Although there might also be some minor cosmetics, IF you know what you're looking at.

CBODY67
 
As mentioned, in stock form, your car should have left hand studs on the drivers side. However, many cars have had lugs replaced by now to right hand thread.

Left hand lugs are stamped...look for an "L" to be sure.

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Not always. Those on my '62 were marked; those on my '70 were not.
 
Not unlike the torque procedures for some modern engine head bolts and such, Torque to "a value", then add 30 degrees of rotation past that. Not unlike the old shadetree method of "as tight as you can, and then another 1/3 turn for good measure" . . . in an age when a torque wrench was an exotic tool advertised in car magazines.

Of course, the newer torque-angle bolts are a special metal to tolerate these things, not supposed to be re-useable, only one use and replace them.

CBODY67
What you're describing is referred to as "torque to yield". If you have an old style beam torque wrench with a pointer and a little red plastic button that slides across the scale, if you torque a fastener up very slowly, you'll see the torque value rise and then as you creep farther towards tight, the button stops. It's at that point that the fastener is starting to stretch. If you keep going you'll break the fastener. But when you stop when the torque value stops increasing you've reached the point where that fastener is achieving maximum clamp load. Many manufacturers now like to install fasteners based on "torque to yield". The other approach to achieving this is to tighten the fastener to "XXX" lbs of torque and then rotate it so many degrees more. Some engineers figure that's a better way to get the fastener to the torque to yield point than trying to actually achieve it the "real" way. When you torque a fastener to a specific torque that is far less than what the fastener can tolerate, you run the risk of having the clamp load the fastener exerts on the clamped joint, relaxing or reducing. And yes, as a following poster has indicated, fasteners torqued to their yield point are only good for one tightening cycle. Once the fastener has started to stretch it doesn't return to its original shape/length when the torque is reduced.
 
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