Title sounds dodgy, but found a great website that lists all of the factory fluid spec and quantities for loads of cars:
Use the menu on the left to choose the right car, i used it to double check the rear axle oil and manual transmission oil needed for the '87. Turns out it really does need 5w30 manual transmission fluid (manual says the same but seemed way too light for a gear oil).
http://www.amsoil.com/mygarage/vehiclel ... FIREBIRD+H _________________
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