Cold Check
Notice: Operating a transmission with the fluid level higher or lower than recommended can result in transmission damage. Do not overfill the transmission. Overfilling will force fluid out of the case through the main shaft openings. Fluid overflow may also drain onto the clutch or clutch brake, causing additional problems.
Do not mix types and brands of fluid, because of possible incompatibility. Do not use fluid additives, friction modifiers, extreme-pressure gear fluids, or multiviscosity lubricants.
Clean all dirt away from around the end of the fluid fill tube before removing the dipstick.
Notice: Do not allow foreign matter to enter the transmission. Dirt or foreign matter in the hydraulic system may cause undue wear of transmission parts, make valves stick, and clog passages.
It is important to check the fluid level cold to determine if the transmission has a sufficient amount of fluid to be safely operated until a hot check can be performed.
- Park the vehicle on a level surface, apply the parking brakes, and chock the tires.
- Run the engine for at least one minute.
- Shift from DRIVE to NEUTRAL, and then shift to REVERSE to fill the hydraulic system.
- Shift to NEUTRAL and allow the engine to idle at 500 to 800 rpm.
- With the engine running at idle, remove the dipstick from the tube and wipe it clean.
- Insert the dipstick in the tube, then remove the dipstick.
- Check the fluid level reading and repeat the check procedure
to verify the reading.
If the fluid level is within the COLD RUN band, the transmission may be operated until the fluid is hot enough to perform a HOT RUN check.
If the fluid level is not within the COLD RUN band, add or drain fluid as needed to adjust the fluid level to the middle of the COLD RUN band. See Fig.. For approved Allison transmission lubricants, see Table..
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Cold Run Band
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Hot Run Band
Fig. 1, Dipstick Markings
Table 1, Approved Allison Transmission Lubricants
Approved Allison Transmission Lubricants
Lubricant Type1
Temperature: °F (°C)
All Allison Transmissions
Castrol TranSynd™ (synthetic)
Above –22 (–30)
Dexron® III
Above –13 (–25)
- Lubricants listed in order of preference. Do not mix types of oil.
Table 1, Approved Allison Transmission Lubricants
Notice: Do not fill above the COLD RUN band if the transmission fluid is below normal operating temperature. As fluid temperature increases, so does the fluid level. Filling above the COLD RUN band when the transmission is below normal operating temperature may result in an overfilled transmission, which causes fluid foaming and aeration. Fluid foaming and aeration cause transmission overheating and erratic shifting.
Note: Perform a hot check at the first opportunity after the normal operating temperature, 160 to 200°F (71 to 93°C) has been reached.
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