Concorde Lug Nut Question

The dealer put my wheels on, so I tested the torque of all of the lugs
(Chrysler spec: 100 ft-lb) when I got home. A few were somewhat over
spec, but nothing too terrible. What I noticed though is that the lugs
and wrench tend to studder when approaching the desired tightness. I
don't recall this happening before, usually the lugs would tighten
smoothly as the torque meter approached 100. Does anyone know why this
happens and if it is a problem? Thanks.

 

Using the wrong size wrench and it's slipping on the nuts?

Bill Putney
(to reply by e-mail, replace the last letter of the alphabet in my
address with "x")

 

You should read your instructions for the torque wrench. Some have to
approach the right torque and won't click or read correctly if the right
torque is already exceeded. In other words they cannot be used to check if
someone already overtorqued the nut.

 

It is due to the lug nuts being dry. Could be the dealer hit them with
solvent to make sure they were clean and dry. Even though it isn't
recommended, I tend to spray a little WD-40 on mine after I install the
nuts. This usually leaves enough residue so that they don't shudder
next time I torque them down.


Matt

 

It is due to the lug nuts being dry. Could be the dealer hit them with

The published torque spec assumes dry nuts and studs.

Richard.

 

True. Don't lubricate the studs and nuts, but lightly wire brush them
to remove dust and grit accumulation, particularly brake dust.

 

I know. That is why I said "it isn't recommended" above.


Matt

 

I was using the right size socket (14 mm) and the fit was fine. Previously
when I've rotated my tires, I 've usually found that the lugs tightened
smoothly to the proper torque, that's why I was surprised here. Thanks!

 

I don't think that's the issue. You are correct that you can only measure the
torque while the bolt is moving, but to measure, I loosened slightly until the
lug moved, than retightened, all while watching the torque reading. I did this
in the usual star pattern to all of the 5 lugs on each wheel.

What happened is that the lugs shuddered while tightening ( and while
loosening). Because I"ve never experienced that before, I am curious if it
means something is wrong.

Thanks!

 

I experience that often with dry lug nuts and studs, so I don't think
you have anything wrong. Just the nature of the beast. That is why
virtually all fasteners other than lug nuts must be lightly lubricated
before torque is applied. Lug nut torque is specified for clean and dry
threads.


Matt