Pete & Aprille Chadwell, Randall Young & I have been discussing the
correct(?) torque for the pinion nut.
In summary the Bentley manual has listed on page 346 the pinion nut torque
as 90 - 120 lbf in, on page 54 the pinion nut torques is 90 - 120 lbf ft.
> So why is the "lbf ft" wrong and the "lbf in" right ? Lee (and the last
> person to work on your pinion) may well have the same manual. It's even
> not unheard of for one manual to perpetuate a misprint found in another
> manual !
Yes indeed I was working from the Bentley manual.
The 6 Tech manual states the following about installing a NEW pinion gear:
"Next, it is time to try to set the preload on the pinion bearings. Start by
placing the original spacer and shims on the shaft plus about 0.010" of new
shims. Put on the front bearing, driving flange, and nut. Torque the nut
down a little at a time until the shaft no longer turns freely or you reach
90 foot pounds (ft. lbs.) of torque on the nut. However, in no case should
it take more than 12 inch pounds (not foot pounds) to turn the pinion. If
too tight, add shims; if too loose, take some out".
Looking back at page 346 of the Bentley manual we note the metric units
provided with the "90 to 120 lbf in" statement are "12.4 to 16.6 kgf m"
which equals 90 to 120 foot pounds. From this I must conclude that the
Bentley manual is wrong and 'inch pounds' should be 'foot pounds' for the
pinion nut torque listed on page 346.
It should be noted that for both of the pinion nuts that I have removed it
required almost no torque to back off the nut. I can only guess that the
spacers have worn down and the effective pinion nut torque has decreased. I
won't even begin to guess what the correct torque should be since the spacer
wear will vary from unit to unit. I simply reinstalled the nut to 10 foot
pounds, 120 inch pounds like the happy idiot that I am. So far I've got 6000
miles on the unit with no problem .... YET!
Lee Janssen
Village idiot
Denver CO
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