I know this has probably been asked a million times but I am just not getting it. As of right now my 54' has 215/70-15 on them. I don't like how small they look with the big fenders so I want to go up in tire height. I was thinking 255/60-15.
Can anyone confirm that I should be able to do this without any issues?

 

Looking at a tire size calculator, the 255's would be 1.6" wider and only 1/4" taller than your 215's. I would just measure your clearances with the frame/steering at full lock, as well as your fender clearance. Height is effectively the same, and teh 255's would stick out about 3/4" at the tread/sidewalls more than you are now.

I can tell you on my 50, I have 255's on the rear (stock suspension) and have plenty of clearance with neutral backspace wheels, and I like the look of the wider tire. The front of mine currently has 235/60/15's and they have plenty of clearance too. I will probably replace them with 255's before I hit the road, but I got a great deal on the set and my intention was to just use them for mock up anyway.

The other thing to watch is your wheel size. The book says you need at least 7" wide wheels for the 255's (that is what I have and they fit fine).

Here is a pic, but it doesn't show much.



And here is an older on that might show a bit more of the fender fit.

 

I've found that 225:75/R15s are pretty much a perfect size for these trucks. I've used them on two bonus built trucks now and very happy with them. The 53-56 may be able to take a little larger size...

https://www.ford-trucks.com/user_gal...255464&width=1

 

Here's the size's I went with.
front wheels- 15x7 3.75 backspacing Crager SS
front tire- 225x75 R15 Firestone
rear wheel- 15x8 4.5 backspacing Crager SS
rear tire- 255x70 R15 Firestone

Here are a couple of links- Tire Size Calculator
Tire Size Calculator


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