Powertrain, generic · Transmission

P0897 Transmission Fluid Deteriorated

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

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).

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)

Symptoms

  • CHECK TRANS lamp on
  • TRANS SERVICE or wrench indicator after each start beforehand
  • Driving usually normal

Repair estimate

DifficultyMediumDIY possible
Parts and labour€100–400
Time0.5–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

transmission fluid filtertransmission fluidtransmission control module

Related codes

P088AP088BP0218P0711P0710

References: static.nhtsa.gov, patents.google.com, gearsmagazine.com.