I have a 75 f250 with 16.5 inch rims, they are 8 bolt pattern. I was thinking since there are 5 tires vs the 4 I currently have as a spare would they work on my 86 f350 8 bolt pattern crew cab.

 

90% sure they're the same

 

they are the same ford didn't change until the early 2000s

 

Two things of note:
1. 16.5" rims and tires are harder to find these days compared to 16" rims. One cheap source for 16.5" tires is military(humvee) tires; If you're looking at someday putting large tires on your truck, you can get those cheaply. Also, I've seen superswampers in 16.5" size.

2. If you need, your truck will get down the road with 1 oddball tire(large or small). It'll feel weird though, and I'd not do it for *too* long. This means that you can use one tire from set A as a spare for set B, as long as set A fits.

3. At some point, if you need a spare 16" rim so you have a set of 5 of those as well, look around junkyards. But be aware that there are 8-lug Dodge and Chevy rims which "almost" fit: the hole pattern is the same, but the inner rim is just a hair too small to fit our trucks. Just watch for that, and you can probably pick up things extremely cheap(a rim is a rim, if it'll fit).

 

Humvee tires sounds like a good idea. But yeah to be different and have 2 sets of tires why not. And if I use the one as a spare till I can get a spare 16 inch sounds like itll work just to get off the road. But great idea for the 16.5

 

Question is with humvee tires are they any good. Ive read mixed reviews. Load capacity looks like not much either. But i was wondering if anyone has them and are they worth it?

 

Theyre fine on the street and sand, decent in rocks, not great in mud. For 100 a tire im not complaining. Get the radials, not the bias. FYIY they are 37"

 

if you have a limited slip rearend, do not put different size rims/tires on it.

a LSD requires the same size left to right.

or your clutches will wear out and start making noise.

 

It would be as a temp spare till I get correct spare and only to move it off the hwy if necessary. But it would be all 16 or 16.5 inch rims, I've been debating in the cooper dicover ht3. Looks like a nice tire there and good price. Put Humvee on the 16.5 as a spare backup tire set.

 

First, do you even have a LS rearend to worry about? If not, it doesn't matter at all. And if it happens on the front... it doesn't matter.
It may drive a little funky if you've got an odd size tire(like, inches different), but like you said, it's an emergency spare.

I drove like 15 miles with 3X LT235-85-R16's and 1 36.5X12.5X16.5 humvee bias-ply tire(It was on the right rear). I went highway speeds for some of it, though it felt a little odd with the right rear corner being so high. Mind, I don't have a LS rearend. And it was only 15 miles.

 

My code I think is c5 on door tag I'll dig up the rest of axle code this weekend.