>Now that I have the beast running after two years of problem, I thought
>I should change the gear box oil. How do I do that? I see the plug to
>drain it but where do I put the oil in?
The fill plug is a square sided plug on the side of the gear
box. Driver's side for us USA left hand drive cars.
I always recommend LOOSENING that plug first (big cresent
wrench), THEN removing the drain plug. I like to use a
big magnet and get an idea of what is in the fluid being
drained. Not uncommon to see shiny metal in there, but there
should not be anything so large to feel when rubbed between
your thumb and index finger.
On a 4 speed, if you see any little metal rods about 1/32" x 1"
long. DO NOT DRIVE THE CAR! Those are support bearings for the
countershaft. Caught in time, it is a simple repair.
GEAR OIL: I like 85W/90 Castrol Gear Oil. Get a bucket of
HOT WATER and drop the bottle in for 10 minutes. Pull the bottle
out, and wipe off all the water. Much easier to pour, or pump,
when it is warm!
Ditto for the rear end! Usually I change trany and diff fluid
every two years. Cheap insurance.
I also like the Redline synthetic gear oils. The syncho's feel
notchy at first, but shifting improves over time. Still not sure
if I got used the the feel, or if the additives helped worn
synchro's spin up quicker.