no it shouldn't damage it - some manual gearboxes use it as standard, namely freight rover, triumph tr7,rover sd1 models [all 5 speed] - it is used to overcome difficulty engaging some gears, but gear rattle is sometimes evident on tick over. hope this helps.
k
April 2009
will work for a while, but auto gear box oil too thin for manual box. bearings will wear out inside gearbox eventually.
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