I have an 88 300E. Transmission shifts fine when cool. After its been driven a while in the hot weather it doesn't want to shift from second. What could be the problem. I'm not a great mechanic but am wondering could the trans filter be whats causing this problem?

When was the last time it had the fluid and filter changed?? Ideally it should be done every 15-20,000 miles....more if its driven in a hard environment (mostly city driving)

It could also be a bowden cable adjustment problem.

How many miles on it?

And welcome to the forums! Ideally you should have posted this in the "Tech" section.

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