My 2001 Residency MH blew a hole in its hoses a few years ago. It made an awful mess when it happened. I was trying to level and it wasn't acting right. I got out to look and saw I huge spot of fluid all around the leak. Thank goodness my spot was gravel. If it had been concrete or blacktop, I'd would have been up a creek.
Since then, I've replaced all the hoses and all the leaks are gone. If one of your hoses has a leak and you're going to keep your unit for awhile, don't patch it, replace the whole length. Hoses don't last forever. If you're able replace them all and be done with it for several years.
The Residency had double acting Kwikee levelers and it took 200 ft of hose to run two hoses to each jack. Lucky for me, someone on eBay had several 50ft lengths and sold them to me a whole lot cheaper than I could have bought them for at NAPA. I was able to cut them to length and used the shorter pieces for the front near the pump and longer ones for the rear jack - there was no waste. I had NAPA crimp the ends on for about $100 in total - 8 hoses needed 12 ends. I was able to use 4 of the fittings on one end of the hoses I bought.