Thank you for your question.
I will be happy to assist you. I looked up the transaxle for your tractor. This transaxle has two seals on each axle. I have posted an image below that shows where the seals are located. To replace the seals the transaxle has to be removed and taken apart. If you decide to do this, I recommend thoroughly cleaning the outside of the transaxle before you start taking it apart. The reason is if any dirt gets into the transaxle, they do not last very long. Please click on the following link if you would like to order the parts.
Parts for Craftsman tractor model 917.271021
I hope this is helpful. Please let me know if you need further assistance.
If you do not feel confident repairing this problem yourself, then you can have it repaired at your home by a Sears technician. Here is a link for the website:
Sears Home Services
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