Allison's 'Prognostics' in its fourth and fifth generation controls (1000 to 4000 series, buses and trucks, from 2009) has no fluid quality sensor: the gearbox module calculates. No car maker is known to use these codes. Its oil life monitor counts down the remaining fluid life from operating hours, distance, shifts and load factors such as fluid temperature, open converter and retarder use. With little life remaining, TRANS SERVICE shows for two minutes after every start; if the change and reset do not follow within a set period, CHECK TRANS lights and P0897 becomes active. Correct calculation assumes approved fluid (TES 295/668).
Medium severity. Can I keep driving?Drive gently to a repair shop. If it slips, you hear clunks, or it loses its gears, do not keep driving.
Symptoms
- CHECK TRANS lamp on
- TRANS SERVICE or wrench indicator after each start beforehand
- Driving usually normal
Most likely causes
- Fluid change interval exceeded
- Fluid changed without resetting the oil life monitor
- Heavy duty (heat, stop-and-go, retarder) shortens calculated life
- Prognostics disabled afterwards (Allison special case)
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
What each character of P0897 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 8: Transmission
- 97: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0897?
Drive gently to a repair shop. If it slips, you hear clunks, or it loses its gears, do not keep driving.
What causes code P0897?
The most common causes are: fluid change interval exceeded; fluid changed without resetting the oil life monitor; heavy duty (heat, stop-and-go, retarder) shortens calculated life.
Related codes
- P088ATransmission Fluid Filter Deteriorated
- P088BTransmission Fluid Filter Very Deteriorated
- P0218Transmission Fluid Temperature Sensor A Over Temperature Condition
- P0711Transmission Fluid Temperature Sensor A Circuit Range/Performance
- P0710Transmission Fluid Temperature Sensor A Circuit
Sources
- static.nhtsa.gov: MC 10155474 9999
- patents.google.com: US8050814
- gearsmagazine.com: looking information allison prognostics
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.