Lower A-arm torque-spec

[Jon Pike <jhpike@xxxxxxx>]

> I've had great difficulty with these torque specs, I also stripped a thread
> when someone told me the spec was 60lb-ft, which meant dismantling the entire
> suspension to replace (spring-out..again). But after a quick discussion with
> Tom Sahines, I saw common sense. My problem had been that the overly-tight nuts
> caused the a-arm bushes to bind on the x-member-rod (back-beam?), so my
> suspension had huge "stiction" and wasn't working right at all. 
>  
Ouch..  At least I hadn't put my springs in beforhand. 
Kinda worrysome that 60 ft-lbs was enough to strip one..  Maybe that 
confusing sounding 5.6-5.9 kgm ( 40.1 - 42.5 ft-lbs)  is actually the 
right spec?  In my manual it seems they start to say that is it, but end 
up saying that's the torque for the 4 support to chassis bolts.

Tom's answer you mention seems to imply that the lower A bushes are 
supposed to be loose and turning, as opposed to being tightly locked?  I 
thought the common wisdom was that the lower A bush was more like a 
bearing,  and was supposed to be locked to the support...
OH... I see,  your car is a 67..   I heard that the earlier ones were 
brass bushes or something, and really were bearings that needed to 
float.  Possibly yours is of that style.


> In my opinion, the reason there's no torque spec in most books is because
> you're supposed to do it by feel. Tighten it up to a good tight feel, back it
> off a smidgen, then smack the washer over and you're done. The washer stops the
> nut coming undone, and even in the unlikely event of the nut backing off - the
> A-arm won't come apart because the spring pan holds the arms together, so that
> they can't fall off the back-beam.
>
> 90lb-ft is just plain crazy - there are about 2.5 little fine threads inside
> those thin nuts. The above is just my experience but I know that 90lb-ft will
> destroy something.
>
> - -Richard
> 1967 GTV
> San Jose
Naaaa,  there's at least 5 1/2 or 6 threads on that nut!!  ;-)  I 
thought it was wild myself on first impression,  then talked myself into 
it thinking how high some other similary large fastenters go.

I was doing this in the process of changing out all the bushings,  and 
boy were my originals shot,  but my concern was for finding the left 
rear pin rather chewed from the inner shell coming loose and wearing  
the heck out of the pin.  Others have commented on the Digest to watch 
out for that. So I wanted to make sure the replaced and OK ones wouldn't 
get loose.

It is kind of curious that the factory shop manual shows no spec for 
that,  while detailing the others.. but it could be a typo..   I really 
wish I did it that way,  since I felt it snug up and would have 
stopped,  if not for being in "must make torque wrench click" mode.

Now if it was 8.8 or 10 spec steel,  which I guess we have proved it 
surely isn't,  perhaps 100 ft-lbs would have been about right.  Goes to 
show...  DON'T GUESS!!

Jon  (torqued off in Irvine)
77 Spider
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