Some of the 'exclusions' are anything that is not lubricated bearing. So a failure of exhaust headers, and they start leaking might not get covered.
Also I have heard of a warranty company requiring that you must change the oil every 3,000 miles, or coverage will end. So miss a receipt for a oil change, and basically the company can say "This is why we did not cover anything, you skipped a oil change back in 2017" and your warranty is not valid anymore.
So read the fine print before going to sign the paperwork. How they can say lack of maintenance on the engine oil changes will effect the coverage of the refrigerator is beyond me. . . Yet I can understand that they want to cover themselves by not covering a seased engine caused by not changing the oil every 5,000 - 7,500 miles as recommended by Ford.
Also it is a insurance plan. They plan on charging enough to cover any expected break downs. So the price is $4,300. Some of that will go to the salesman, some to the dealership, some to the actual insurance company as a profit. About $2,000 - $3,000 will actually go into a fund to make repairs. Their hope is that you will not have more than $1,000 in covered repairs. Their fear is that you might have more than $3,000 in covered repairs.
Your hope is no breakdowns at all! But your fear is that should something break, it will get covered, and you will not be out more than the minimal fee for each breakdown. Yet at the end of 5 years you will be out the $4,300 if you buy the policy.
I don't think that the policy is worth $4,300. Ask if you can get a better price. They probably will come down $1,000 or so. . .
Your engine will last well into 150,000 miles. I do not know how many miles you plan to drive it each year. The transmission might have been replaced, or not? It probably should last up to about 120,000 in motorhome service until needing a rebuild. That can cost around $2,500 - depends. That is probably why the insurance is so expensive on such a older coach. . .
Good luck!
Fred.