I don't know if Jayco has made major changes to the X17Z, but that has been a single axle trailer for the past several years at least. You might want to checkout Jayco's website or order a brochure. Better yet, go see one at a dealer.
I pulled a X17Z with a 2010 Tacoma Xtracab, towing package, and 6 cyl. Handling was not a problem, but if I went faster than 60 mph I only got 7 - 8 mpg. There should be some old threads on this forum about that you can find with a search.
If you get serious about the 17Z, measure the tongue weight with a scale while it's still at the dealer.
BTW, our 17Z made several roundtrips between Cincinnati and St. Petersburg, Cincinnati and Yellowstone, Michigan's UP, and many local trips. It was a great TT, but our situation changed and we needed bigger.