Transmission Fluid Cooler Flushing and Flow Test (J 35944-A): Notes

WARNING: This page is about a different car, the 2009 GMC Yukon and 2009 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.

GM studies indicate that plugged or restricted transmission oil coolers and pipes cause insufficient transmission lubrication and elevated operating temperatures which can lead to premature transmission wear-out. Many repeat repair cases could have been prevented by following published procedures for transmission oil cooler flushing and flow checking. This procedure includes flow checking and flushing the auxiliary transmission oil cooler, if equipped.

NOTE: Use the J 35944-A: oil cooler flusher or equivalent to flush the transmission oil cooler and the oil cooler pipes whenever the transaxle is removed for the following repairs:

Note - FWD:

Torque converter
Oil pump
Oil pump drive shaft
Drive sprocket support
Transaxle overhaul complete
Transaxle assembly replacement

NOTE: Use the J 35944-A: oil cooler flusher or equivalent to flush the transmission oil cooler and the oil cooler pipes whenever the transmission is removed for the following repairs:

Note - RWD:

Torque converter
Oil pump
Turbine shaft
Transmission overhaul complete
Transmission assembly replacement

Only GM Goodwrench DEXRON®VI automatic transmission fluid should be used when doing a repair on a GM transmission.

Time allowance for performing the cooler flow checking and flushing procedure has been included in the appropriate labor time guide operations since the 1987 model year. The service procedure steps for oil cooler flushing are as follows:

Cooler Flow Check and Flushing Steps

Special Tools
Preparation
Back Flush
Forward Flush
Flow Check
Clean-up

Special Tools

J 35944-A: Transmission Oil Cooler Flusher
J 35944-22: Transmission Oil Cooler Flusher Fluid
J 35944-200: Cooler Flusher Adapter
Measuring cup
Funnel
Water supply, hot water recommended
Water hose, at least 16 mm (5/8 in) ID
Shop air supply, with water/oil filters, regulator and pressure gage
Air chuck, with clip if available
Oil drain container
Pail with lid 19 L (5 gallon)
Eye protection
Rubber gloves