What is proper torque setting for lugnuts on a 92' 100?

[chan@bach.seattleu.edu]

Hey guys,

Can anyone out there tell me what's the proper torque setting for the lugnuts
on a '92' 100? Is it 80ft/lbs or tighter than that? It's not listed in the
owners' manual and also not any doorjams or gas flap stickers. I got my tires
re-balance and rotate and the guy at the tire shop hand torqued it to 80ft/lbs
but they seemed to come loose even though I checked and re-torqued after I got 
home. I have two torque wrench at home one cheapo one and one expensive one and
I checked with both. It seemed like just the front ones have that problem. The
threads on both the lugnuts and the hubs are fine i.e. clean and not strip. 
It's never been over torqued. 

This morning I re-torqued the front ones to 82ft/lbs before I went out for
a very long drive(6 hours). They seemed to stay tight but I still want to 
know the proper torque setting(I did loosen all the wheels have each off
the ground and tighten them as much I could before I lower them down to do
the final torquing. 

Thanks,

Anthony Chan
chan@seattleu.edu
92' 100 V6