GM Service Manual Online
For 1990-2009 cars only

Information on Water or Ethylene Glycol in Transmission Oil

Subject:Information on Water or Ethylene Glycol in Transmission Oil

Models:2000-2009 GM Passenger Cars and Light Duty Trucks (Including Saturn)
2003-2009 HUMMER H2
2006-2009 HUMMER H3
2005-2009 Saab 9-7X
with Automatic Transmission



Water or ethylene glycol in automatic transmission fluid (ATF) is harmful to internal transmission components and will have a negative effect on reliability and durability of these parts. Water or ethylene glycol in ATF will also change the friction of the clutches frequently resulting in shudder during engagement or gear changes, especially during torque converter clutch engagement.

Indications of water in the ATF may include:

    • ATF blowing out of the transmission vent tube
    • ATF may appear cloudy or in cases of extreme contamination have the appearance of a strawberry milkshake
    • Visible water in the oil pan
    • A milky white substance inside the pan area
    • Spacer plate gaskets that appear to be glued to the valve body face or case
    • Spacer plate gaskets that appear to be swollen or wrinkled in areas where they are not compressed
    • Rust on internal transmission iron/steel components

If water in the ATF has been found and the source of the water entry has not been identified or if a leaking in-radiator transmission oil cooler is suspected (with no evidence of cross-contamination in the coolant recovery reservoir), a simple and quick test kit is available that detects the presence of ethylene glycol in ATF. This kit should obtained and the ATF tested to make an accurate decision on the need for radiator replacement. This can help to prevent customer comebacks if the in-radiator transmission oil cooler is leaking and reduce repair expenses by avoiding radiator replacement if the cooler is not leaking. These test kits can be obtained from:

Nelco Company 1047 McKnight Rd South Saint Paul MN 55119 Phone: 651-738-2014 Fax: 651-738-9447 E-mail: [email protected]

Orders are shipped standard delivery time but can be shipped on a next day delivery basis for an extra charge. One test kit will complete 10 individual fluid sample tests. For vehicles repaired under warranty the cost of the complete test kit plus shipping charges should be divided by 10 and submitted on the warranty claim as a Net item.

Important: If water or coolant is found in the transmission, the following components MUST be replaced.

   • Replace all of the rubber type seals.
   • Replace all of the composition-faced clutch plates and/or bands.
   • Replace all of the nylon parts.
   • Replace the torque converter.
   • Thoroughly clean and rebuild the transmission, using new gaskets and oil filter.
   • Flush and flow check the transmission oil cooler using J45096. Refer to Corporate Bulletin Number 02-07-30-052D or newer - Automatic Transmission Oil Cooler Flush and Flow Test Essential Tool J45096 TransFlow.
   • Thoroughly inspect the engine cooling system and hoses and clean / repair as necessary.