Classic Winnebagos & Vintage RVs

I'm buying a set of 19.5 5 lug rims for my 72 D25 Chieftain, and I needed to know what the proper size radial tire would be. My Winnebago is on a Dodge 500 chassis with the 413 engine. 

Would I be correct in saying your replacing 17" 5 lug split rims with the 19.5" 5 lug rims?  Do you have front brake drums or front disk brakes?  If replacing 17" rims and have front drum brakes then you have a M375 chassis.  The M500 (RM400) chassis did not start until 1973 and had a 440-3 in it.

I was told it was a dodge 500 chassis years ago but whatever it is, its a 1972 D25 chieftain with 5 lug 17" split rims that i'm converting to 19.5" radial rims so I can use the less expensive tires, plus if one of the radials blows out it will be much easier to replace than the split rim bias ply tire. Do you know what the proper size tire would be for a 19.5" rim that could support the weight of the 25' Winnebago?

What is the rating on the bias tire? I had a 33.6 ft Daybreak last year and I put Samson 225/70/19.5 tires on it. I believe they were rated at 3970 for singles if I remember right. Go to simpletire .com  type in the size tire you think you may want. That'll bring up a list of tires and their prices. Then you can look at the specs of the tire you desire. You may want to measure the height of your originals and try to match up to that also.

I have 225/70/19.5 on my M500

Does anybody knows where i can find the 19.5 rimms with the 5 lugs
I am driving on the 750x 17 bias ply tires now .

I ended up buying a set of 19.5 rims off a mid-70's Georgie-Boy motorhome that was being scrapped.  They are out there....

Are these the same 19.5 rims that are used on the later 80's GM chassis? They are ten bolt for the back but five bolt in the front, same rime, has ten holes.