Eaton TRSM0515, Service Manual

Page: 8 / 88

LUBRICATION
Operating Temperatures
—With Eaton
®
Roadranger
®
CD50 Transmission Fluid
Heavy Duty Engine Oil
and Mineral Oil
The transmission should not be operated con-
sistently at temperatures above 250°F (120°C).
However, intermittent operating temperatures
to 300°F (149°C) will not harm the transmis-
sion. Operating temperatures above 250°F
increase the lubricant’s rate of oxidation and
shorten its effective life. When the average
operating temperature is above 250°F, the
transmission may require more frequent oil
changes or external cooling.
The following conditions in any combina-
tion can cause operating temperatures of over
250°F: (1) operating consistently at slow
speeds, (2) high ambient temperatures, (3) re-
stricted air flow around transmission, (4) ex-
haust system too close to transmission, (5)
high horsepower, overdrive operation.
External oil coolers are available to reduce
operating temperatures when the above condi-
tions are encountered.
Transmission Oil Coolers are:
Recommended
— With engines of 350 H.P. and above
with overdrive transmissions
Required
— With engines 399 H.P. and above with
overdrive transmissions and GCW’S
over 90,000 lbs.
— With engines 399 H.P. and above and
1400 Lbs.-Ft. or greater torque
— With engines 450 H.P. and above
—
With EP or
Multipurpose Gear Oil
Mild EP gear oil and multipurpose gear oil are
not recommended when lubricant operating
temperatures are above 230°F (110°C). In addi-
tion, transmission oil coolers are not recom-
mended with these gear oils since the oil
cooler materials may be attacked by these
gear oils. The lower temperature limit and oil
cooler restriction with these gear oils gener-
ally limit their success to milder applications.
Proper Lubrication Levels
as Related to Transmission
Installation Angles
If the transmission operating angle is more
than 12 degrees, improper lubrication can oc-
cur. The operating angle is the transmission
mounting angle in the chassis plus the per-
cent of upgrade (expressed in degrees).
The chart below illustrates the safe percent
of upgrade on which the transmission can be
used with various chassis mounting angles.
For example: if you have a 4 degree transmis-
sion mounting angle, then 8 degrees (or 14
percent of grade) is equal to the limit of 12
degrees. If you have a O degree mounting
angle, the transmission can be operated on a
12 degree (21 percent) grade.
Anytime the transmission operating angle of
12 degrees is exceeded for an extended
period of time the transmission should be
equipped with an oil pump or cooler kit to
insure proper lubrication.
Note on the chart the effect low oil levels
can have on safe operating angles. Allowing
the oil level to fall 1/2" below the filler plug
hole reduces the degree of grade by approxi-
mately 3 degrees (5.5 percent).
Proper Lubrication Levels are Essential!
Transmission Mounting Angle
Dotted line showing “2 Quarts Low” is for
reference only. Not recommended.