Leaking Windows

[retiredhappy]

Having problems with two of my sliders leaking on the inside where the window slides back and forth. I caulked around the outside there the "trim" meets the RV. Also caulked where the "trim" meets the window. Oops, couldn't open the windows. My RV guy made sure the "drain holes" were open and draining well. That didn't solve the problem. Only leaks in a hard rain where the water is running down the windows. Track gets so full of water that it complete soaks a bath towel. RV buy trying to get new track that window sits in but manufacturer out of business. Any suggestions are welcome.