My first suggestion is to check the fluid level. Next, due to the age of your coach, I'd suggest changing the fluid. It's MD3 automatic transmission fluid, and you'll only need a gallon or so. I just syphoned out the old fluid from the reservoir and poured the new fluid in. I then recycled the jacks a few times to bled off any air in the lines. Finally, spray the shinny part with silicone spray. The seals get dry and can really slow down retraction, and possibly may effect extending as well.
Holiday Rambler Navigator DP, Hummer, and Honda VT1100C Shadow