Your owners manual will give you the recommended schedule. You may have a maintenance book as well with the service schedule. I would not go farther than 50,000 miles but if you drive it hard I would change it more often. If the fluid changes color or smells burnt then change it and the filter immediately.
The fluid cannot be changed like other AT. Only half of the oil can be drained and the filter is not accessible. Must take to a dealer to do the job right.
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