On the tires... (everybody on here knows I'm obsessed with tires by now, since I had two failures in 2 months...LOL!) Check the date codes on the tires and if the rest of them are older than about 6 years, seriously consider replacing them. If you don't know how to read the date code, then do a quick Google search on how to read tire date codes. Basically, at the end of the DOT number, in its own little box, there should be a 4-digit number. The first two numbers of that 4-digits is the week the tire was made. The last 2 are the year it was made. IE., A date code of 2214 means that the tire was made during the 22nd week of 2014. And be careful running 80 on a motorhome. I'm not aware of any of the tires that have a speed rating of more than 75. Just not a good practice to run that fast on something that big and top-heavy too.
On the batteries, ....How old are they? If they're more than a couple of years old, you'd probably be just as well off to get new house batteries and start from there. And if you don't trust your disconnect switch for when the coach is stored, then take the negative cable loose from the battery terminal and cover it so it can't be accidentally reconnected until you're ready to use it again. That will guarantee that no electrical drain is happening when stored.
If your jacks are not working, make sure the hydraulic fluid reservoir has fluid in it. Make sure you are getting power to the hydraulic pump. Make sure the jacks are not bent, keeping them from extending. Make sure there's nothing obstructing them, like dirt or other foreign object or even a long-term storage set screw or something like it. Make sure that all caps and plugs are in place so the hydraulic fluid can actually push the jacks and not run out.
Not sure on your coach, but mine holds 70 gallons of fresh water, 35 black and 35 grey. I suspect yours will be similar, give or take 5 gallons.
I would suggest that you poke around the internet a while and see if you can find an Owner's Manual that should have all the relevant specifications you'll need.
Good luck! Post some pictures when you can!
1999 Holiday Rambler Endeavor, 36' Gasser
Triton V10, Ford F53 Chassis
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