Have Transmission Questions? Ask a Mechanic for Answers ASAP
Hi my name is***** will be glad to help. Check inside the filter and pan for signs of friction material or fine metal. Sometimes it will look like anti-seize in the oil. If found you have internal problems. There are pressure ports to test pressures as well if the oil and filters show no signs of a mechanical failure
The seals sitting are the worse thing for an automatic transmission as they dry out and become brittle and the new oil has detergents to help clean sludge etc so if there were any troubles in the transmission and the sludge was helping an o ring seal, the new oil likely cleaned that away.
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Troubleshooting and adjusting
Maintenance and troubleshooting