Buick 1993 Roadmaster Owner's Manual page 258

How to Add Fluid:
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. See "Recommended
Fluids and.lLubricants" in the Index.
If the fluid level is low, add only enough
of
the proper
fluid to bring the level up to the COLD area for a cold
check or the HOT area fora hot check. It
doesn't take
much fluid, generally less than a pint. Don't overfill.
we
recommend you use only fluid labeled DEXRONBIIE,
because fluids with that label are made-especially for
you automatic transmission. Damage caused by fluid
other than DEXRON@IIE is not covered by your new
vehicle warranty.
0
After adding fluid, recheck the fluid level as
described under "How to Check.77
0
When the correct-fluid level is obtained, push the
dipstick back in all the way.
Rear Axle
When to Check and Change Lubricant:
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change it. See
"Periodic Maintenance Inspections" in the Index.
How to Check Lubricant:
If the level is below the bottom of the filler plug hole,
you'll need to add some lubricant. Add enough lubricant
to raise the level to the bottom of the filler plug hole.
What to Use:
Standard Differential
Use Axle Lubricant (GM Part No. 1052271) or SAE
80W-90 GL-5 gear lubricant.
Limited-Slip Differential
To add lubricant when the level is low, use Axle
Lubricant (GM Part No. 1052271) or S A E 8OW-90
GL-5 gear lubricant. To completely refill after draining,
add 4 ounces (1 18 ml) of Limited-Slip Differential
Lubricant Additive (GM Part No. 1052358). Then fill to
the bottom of the filler plug hole with Axle Lubricant
(GM Part No. 1052271) or SAE 80W-90 GL-5 gear
lubricant.