I am looking at some wheel/tire combo's on Craigslist. Looking to go to 17" wheels for eventual 3rd gen brake conversion. Question in the short run is...can I use the spare off of my old 16" rims as long as I've not made the brake conversion? According to tire calculator there is a 1" difference between the same tire size from 16-17" rims. I don't have posi rear axle.

I'm kinda cheap. Rebuilt my rears a year ago with new rotors. So I want to do the front conversion first. Is it ok to do the fronts now and rears at a later date?

Some good deals on Craigslist for takeoff wheels and tires. Like $400 for tires with 75% tread. I paid $1,000 for my last set of tires alone. 55,000 miles and thin.

Not the best case situation, but if I had to I would only use the spare on a steering axle rather than drive axle.  

 

 

I would really look for a 17" steel rim with a cheap used tire though.

You'll need all 5 wheels to be 17" wheels. There is no way to use a 16" wheel once the brake upgrade is done. Personally I would not mix and match tires sizes on a differential axle because even small difference will put much more work on the spider gears.

A 265/75R16 is almost identical to a 265/70/17

A 245/75R16 is almost identical to a 245/70/17

 

Would I use a 16" as a spare... I am lol

 

If you're honest with yourself, most peoples spares are new tires, most tires pop when there under 1/2 tread,  The difference in height from tread wear alone would be more then what you'd notice with the sizes above.

What he said ^^^^^^^

Lets say I found out how different size tire can rip apart a 1972 dodge Power Wagon front axle. Very costly mistake... If the 2 tire sizes are on a differential axle there will be damage. But if its a solid axle or front axle of 2WD then your safe. Well kind of... It still not suggested because the steering will be affected.

A 265/75R16 is almost identical to a 265/70/17

A 245/75R16 is almost identical to a 245/70/17

Would I use a 16" as a spare... I am lol

If you're honest with yourself, most peoples spares are new tires, most tires pop when there under 1/2 tread, The difference in height from tread wear alone would be more then what you'd notice with the sizes above.

You're right about these two tire sizes. I'll look for 265/70-17. Calculator says exactly the same as 265/75-16.

17" steel wheel and used tire can be found for under $100 around here

That's what I'm looking for around here. Looking at one set that has 14,000 miles on em. That'd get me by a couple years. Any ideas how the original michelins were on these trucks. From pictures they don't show a model. Just load rating of E.

Since nearly all 17" sizes are 70 series vs 75 series on a 16" the overall diameter is nearly identical.

As long as you don't have a locker or spool you will be fine with a slightly different sizes side to side as that is the purpose behind a differential and the axle will just think you are always on a corner.

If you're honest with yourself, most peoples spares are new tires, most tires pop when there under 1/2 tread

 

LOL... You might want to look under my truck. I still got a nearly brand new Mitchlin tire under mine. I've only used it 3 times and maybe 100 miles total. I'm guilt of the tire offset spare wise too. I've got a 265/75 R16 spare and running 235/85 R16 tires. So that 1 rev per mile difference. Here soon I'll pull that spare and replace it with a used 235.

I would stay with all the same size. I've purchased several deals on craigs list that will sell for more money now than before. Simply cause they were good deals originally and now are worth more. I store up good deals in my shop even when I don't need them cause they could not be passed on at the time. I finally got a screamin deal for matching spare rims on both my trucks.

 

What got me hooked, was a set of e rated tires like new 90% left, mounted on Alcoa rims for $400 . That was too cool.

I just took a look at the Alcoa wheel they are pretty cool looking but $262 per wheel can be rather expensive. So I'd say you got a screaming deal at $400...

LOL... You might want to look under my truck. I still got a nearly brand new Mitchlin tire under mine. I've only used it 3 times and maybe 100 miles total. I'm guilt of the tire offset spare wise too. I've got a 265/75 R16 spare and running 235/85 R16 tires. So that 1 rev per mile difference. Here soon I'll pull that spare and replace it with a used 235.

 

Don't need to, both my 12V'ers have a like new 18 year old spare...   

 

I would stay with all the same size....

 

I understand it's not optimal, but if you compare them (HERE), the size difference would vary more from brand, tire pressure, or a couple hundred miles up or down.  

I just took a look at the Alcoa wheel they are pretty cool looking but $262 per wheel can be rather expensive. So I'd say you got a screaming deal at $400...

If your patient, there are some good deals. Many folks don't know what the Alcoas are worth nor what they are. Thinking they are just some old ford rims. They were offered only on 95 thru 96 Ford 3/4 ton trucks and are still the strongest 16 inch rim you can buy. The only problem being that they are not the 17 inch like you want Joe.

When I look up the price for new Alcoas (you can still get them new) they are around the $260 each price range. Don't know if you can get a 17 inch.

Also be aware of your offset and width of rim will change the diameter and profile of the tires so it can impact odometer and speedometer accuracy. It will be small but its there like my truck with the change of wheels and tire size I've got a 0.5 MPH offset. Small but its there and can't be calculated but it can be measured with a GPS.