I think I've lined up a set of rv 19.5 wheels with 8x19.5 tires on them and before I go ahead and get them I was wondering if anyone could point me towards some pictures of trucks similar to mine with the 19.5 wheels on them? They are a good bit smaller and I'd like to see what they look like compared to the big 'ol 20's. I like how the 20's look, but they're no good if I can't drive on them.
Also, if anyone could tell me how the downsizing in tires affected their overall gearing, that'd be helpful.

Anything else I should know before I get the tires? Here's a pic of one of them, pretty much all the 5 lug rv wheels work, right? Are there ever any concerns with drum brake interference or rubbing between the duals on the rear or anything like that and I can use all the lug nuts/wheel hardware, right?
I'll be replacing some of the tires in the future, 225/70R19.5 seem to be the right replacement for 8x19.5's right?

 

An 8.25-20 tire is about 38" in diameter. A 225/70R19.5 is about 32" in diameter so your F500 will become a low rider. You need to find the largest diameter 19.5 tire possible. It may not even come close to 38".

 

Josh - you should have no issues with rear drum clearance. I believe you have 14" drums which work fine with 19.5s. All your Budd lug nuts will work on tubeless wheels, and you shouldn't have any dual spacing issues with the 19.5s.

I will give the opinion that you don't want 225/70R19.5 tires. They will be only 32" tall and look pretty short on one of these trucks. The 8R19.5s will be between 33" and 34" tall and look much better. The only way to get close to your stock 20s with 37-38" diameter is to find some 22.5s. They will be harder to find than the 19.5s. Stu

 

The gearing and the size/looks I guess are the only thing I'm still wondering about. It's not a fast truck anyhow and never will be, but I'd like it to be pretty driveable. Anyone have any pics of the old trucks with 19.5's on them???

 

I have gone ahead and done the 19.5 swap, and it worked out pretty well. I have 245/75R19.5 on the front and 8r19.5 on the rear. It's a little tight around the rear drums but they fit great, just like Stu said they would.

Here are some pictures, you should be able to compare it to the pics on one of my other posts to see the difference of the truck's look overall. It takes away from the quasi-bigrig look that the huge old tires give it, but it definitely isn't to much of a low rider either.
It did change the gearing quite a lot, but it pulls a load really nicely now, much better than before. It did sacrifice some top end speed of course, but you don't own one of these for top speed.
It feels much more stable.

Let me know if you have any Q's anyone.







And a before picture.

 

Reps for the follow up. Looks good. Too many threads end with no resolution or final story. jmo.

 

Looking good, Josh. Glad it came together. Stu

 

My pastor has been using it to haul gravel on his farm and is calclating 10mpg, between loaded/unloaded, I thought that was pretty good.

 

These trucks are not known for good gas mileage (my 1958 F600 with a 292 V8 gets 7 mpg unloaded) but remember that since you now have smaller tires your odometer is registering more miles than the truck has actually traveled so it's really not getting 10 mpg.

 

It's got a Chevy 327 and a 4spd and the cable drives the Ford cluster, with the smaller tires it puts out some pretty crazy readings. I'll get 55mph on the speedo at around 40mph actual.
He's calculating based on GPS miles vs. fuel used. It's got a one barrel carb and I drive it pretty conservatively, so maybe that helps.