RAM Truck 2011 Owner's Manual page 409

Drain And Refill
On 4500/5500 vehicles, remove the lower bolt to drain
the axle fluid.
1 — 4500/5500 Rear Axle Fluid Fill Plug
2 — 4500/5500 Rear Axle Fluid Drain Plug
Refer to the "Maintenance Schedule" for the proper
maintenance intervals.
MAINTAINING YOUR VEHICLE 407
Lubricant Selection
Refer to "Fluids, Lubricants, and Genuine Parts" in
"Maintaining Your Vehicle" for further information.
NOTE: The presence of water in the gear lubricant will
result in corrosion and possible failure of differential
components. Operation of the vehicle in water, as may be
encountered in some off-highway types of service, will
require draining and refilling the axle to avoid damage.
Limited-Slip Differentials DO NOT REQUIRE any
limited slip oil additive (friction modifiers).
NOTE: Slight noise and mild shuddering may be evident
while turning a vehicle with limited slip differential on
concrete or dry pavement. These conditions should be
considered normal operation of the limited slip differential.
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