I have a 1991 525. It is German specs. I replace the tranny because of the "trans program" error and now I get the same sluggish 3rd gear shifting as the other transmission. However; with this trans I do not get the "trans program" error. What could be the problem? Could it be electrical?

Also, how can I check the fault codes without a fault tester?
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I have a 1991 525. It is German specs. I replace the tranny because of the "trans program" error and now I get the same sluggish 3rd gear shifting as the other transmission. However; with this trans I do not get the "trans program" error. What could be the problem? Could it be electrical?

Also, how can I check the fault codes without a fault tester?
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Is it filled properly, and with new fluid?

Yes