Determine Minimum Flow Rate
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- From the machine display, identify the temperature of the automatic transmission fluid that is stored in the supply vessel of J 45096 .
- Determine whether the transmission oil cooler is steel or aluminum by using a magnet (1) at the cooler flange (2) at the radiator.
- Refer to Minimum Flow Rate in Gallons Per Minute (gpm) table. Using the temperature from step 1, locate on either the Steel MINIMUM Flow Rate table or the Aluminum MINIMUM Flow Rate table the minimum flow rate in gallons per minutes (GPM). Record the minimum flow rate in GPMs and the supply fluid temperature for further reference.
Example:
- Fluid temperature: 75°F
- Cooler type: Steel
The MINIMUM flow rate for this example would be 0.8 GPM.
- Inspect transmission oil cooler lines for damage or kinks that could cause restricted oil flow. Repair as needed and refer to the appropriate GM service manual procedures.
Minimum Flow Rate in Gallons Per Minute (gpm)
| Temperature Range | Steel | Aluminum |
|---|---|---|
| 65 - 66°F | 0.6 gpm | 0.5 gpm |
| 67 - 70°F | 0.7 gpm | 0.6 gpm |
| 71 - 75°F | 0.8 gpm | 0.7 gpm |
| 76 - 80°F | 0.9 gpm | 0.8 gpm |
| 81 - 84°F | 1.0 gpm | 0.9 gpm |
| 85 - 89°F | 1.1 gpm | 1.0 gpm |
| 90 - 94°F | 1.2 gpm | 1.1 gpm |
| 95 - 98°F | 1.3 gpm | 1.2 gpm |
| 99 - 103°F | 1.4 gpm | 1.3 gpm |
| 104 - 108°F | 1.5 gpm | 1.4 gpm |
| 109 - 112°F | 1.6 gpm | 1.5 gpm |
| 113 - 117°F | 1.7 gpm | 1.6 gpm |
| 118 - 120°F | 1.8 gpm | 1.7 gpm |