Frame Extension

Here is a link you might want to dig around in. Can't remember exactly where but they had some remarks about frame stretching and length to handling etc

https://www.fleet.ford.com/truckbbas/

https://www.fleet.ford.com/truckbbas/topics/bodybuild.html

I'm shopping for a class c, don't have one yet. I know different manufactures do have different designs. I'll probably buy a 24 ft. and am wondering what people are actually seeing on their own rigs. The reason has to do with installing a hitch and whether or not an extension will be a problem. Maybe no one looks under their rig and checks? Anyway, thanks.
Stan

My 24' Winnie has an unstretched frame but there are rear extensions. You can usually figure out if it's stretched by looking up the wheel base for the unit. Current production Fords are manufactured with a 138", 158" or 176" wheel base. If the RV wheel base matches one of these, it's very unlikely that the chassis has been stretched.

Just crawl under and take a look, you can see the factory thicker frame end and the lighter frame begin, its usually not over 3 foot long but on a 24 footer you might not have one.

It's variable. A 24' may use the stock wheelbase or may be extended. The rear extension length depends completely on the body builder.