Chris Lillja wrote:
>I think it's important to note that at least one of the specifications in
>the manual for the pinion pre-load is a spec for how much torque it takes to
>TURN the pinion (with the diff sitting on a workbench) not how tight the nut
>should be. (I think.)
>
>Perhaps that the source of the confusion?
>
>7.5-10 ft lbs to turn the pinion "freely" with the nut torqued to 90-100
>FT./lbs? That sounds right.
Well, that may not be a bad idea, except remember that whatever the
pre-load is, the engine has to overcome it in order to turn the rear
wheels. Not that the engine couldn't easily top 7.5-10 ft lbs, but I would
assume that the PRE-LOAD would indeed be expressed in inch pounds. Foot
pounds seems like it would be a little tight, but God knows I've been wrong
before!
Literally, the "source of the confusion" is simply that in the Bentley
manual on page 54 it specifies 90 to 120 FOOT POUNDS and on page 346 it
clearly states 90 to 120 INCH POUNDS. Both of these specs are clearly for
the pinion nut torque, not the bearing pre-load. Apparently the former is
correct.
Given that, I guess it would be wise after all to second-guess the pre-load
specification as well. In this case, it is given on page 346 as 15 to 18
inch pounds, (this would be equivalent to one-and-a-half foot pounds) and
glancing at the metric equivalent, given as .17 to .21 kgf m, that looks to
be about right. I think.
Someone help us out here!
Pete Chadwell
1973 TR6
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