Volvo D11F Operator's Manual And Maintenance Instructions page 78

74 Maintenance and Service
If the temperature reaches 140° C (285° F), stop the vehicle to let the
temperature go down. See the vehicle Operator's Manual for information on
the optional transmission temperature gauge.
If the transmission oil temperatures are consistently high, change oil more
often or install an oil cooler. With lengthy or continuous driving at altitudes of
more than 2 000 m (6,000 feet) above sea level, more frequent oil changes will
be necessary.
Clutch
Check the fluid level in the clutch fluid reservoir. The fluid level should be
between the level marks on the reservoir. If fluid needs to be added, use brake
fluid, DOT 4.
1. Clutch Fluid Reservoir 3. Brake Valve
2. Windshield Washer Fluid Fill