FixVault

Transmission Cooler Flow Test

NOTE: Before performing TRANSMISSION COOLER FLOW TEST, ensure shift cables and linkages are properly adjusted. Ensure fluid level is correct and line pressures are within specifications. See LINE PRESSURE TEST  .
  1. Remove transmission dipstick from filler tube. Install a funnel into filler tube. Raise and support vehicle. Disconnect transmission cooler return line (upper line) from transmission case fitting.
  2. Connect one end of a hose to transmission cooler return line. Install other end of hose into filler tube funnel. Start engine and run at idle with transmission in "N" position.
  3. Note fluid flow at funnel. Wait until flow is constant. This indicates air bleeding has been completed. Fluid flow should be free and heavy. If flow is intermittent or light, check flow from transmission fluid output line to determine source of restriction.
  4. If transmission output line flow is good, restriction is in cooler. Repair as necessary. If output line flow is poor, check for main oil circuit leakage, oil pump defect or a stuck converter charge relief valve.