Ok so as we all know it is hard to find 235 75 16s It is easier to find 245 75 16s however. I drive a 1995 f350 dually.

So here is the million dollar question. Can I switch from 235s to 245s. The truck came stock with 215s.

Can I run 245s safely? No side wall rubbing, no spacers? Thanks.

 

I'm not sure of the rim size your '95 has, and you'll probably have better luck in the OBS forum.

Moved to the '87-'96 forum!

 

Aren't the OEM tires on your dually 85 series tires? ie. LT215-85 R 16?

.

 

Stock size on Dually Fords is 215/85R16.

You can run xxx/75 tires, just lowers the truck some.


Now running 245's on a dually....I don't think that's gonna work safely, as the rear tires will be way to close, if not touching eachother.


Don't forget on a dually, the more space you have inbetween tires, the better. More space = more air flow = better tire cooling.

 

Or did you mean 235/85/16's? They were the standard size for single wheels, not sure about dually's.

 

Yes, what I ment to say was 235 85 16 and 245 75 16. I was in a rush.

But I do see some guys gunning 245s, are they just being dangerous, or what.

 

235/85 would pretty much be your safe limit.

 

i would never run anything other than 215/85/16's (29 x 8.5) on stock pickup dually rims besides 225/75/16's (29.3X8.9) (i run these ones for gear reduction.it was a careful plan/compromise of lowering ride height some,gearing reduction,a bit more footprint so as to not sink and make ruts in peoples lawns when cleaning up from tree work,and rolling resistance for my personal use.) without spacers.

if you want to run a wider tire,like dual (stock srw tire size) 235/85/16 (31.7 x 9.25) or even wider tires such as 245/75/16 (30 x 9.65)
then you need to either;
a.swap your rims out for a set that came off a 4wd cab and chassis dually
or
b.add wheel spacers.

to answer your question,yes those who run dual 235's on stock 2wd offset dually rims without spacers of this area are just being dangerous.
a many lost dually fender have been the result when the tires rub,heat up and blow out!

now,there are also drawbacks to going wider than stock 215/85/16 tires (provided you correctly spaced the tires) such as reduced traction,and fuel economy reduction.
imho,duallies already suffer from these things enough.going wider than stock 215/85/16's (29 x 8.5) makes these DRW cons even worse.

also you want to know if you sport 3.55 or 4.10 gearing.changing your tire size will increase/decrease multiplied torque,and or higher/lower cruising rpms.

i would never run 6 235/85/16 tires.add up the tire width difference for all 6 compared to the 215/85/16 and you'll really see why the fuel economy would take a hit.that's a large increase in rolling resistance.
245/75/16 = you kidding me? forget about the poor DRW traction,with those it would no longer try and and go in the snow in 2wd,but would get stuck and float there just thinking about it.
plus the heavier the tire,the less energy from the fuel going toward forward motion,and of course also means some performance loss,the larger the tire.

choose wisely!

 

I may look into 19.5s. Thet are 225 70 19.5s thoughts?

Also hdxlt going to a smaller tire would be a gear increse not a reduction, on ur truck that is.

 

yeah i guess i could have put the word increase before gear reduction.
your right,i increased my gear reduction device,to provide more torque.
i went from 3.55 gearing to an in between gear ratio of 4.10 and 3.55's which is 3.84:1.
greater performance,increased rpms as side effect.but i drive pretty slow.typically only 45mph zones here,with some double nickle zones on larger roads.with the E40D,im hanging right around 1400ish rpms with these gears,so economy is still good for me.

so if you used a wheel adapter to fit 19.5 rims and run 31 x 8.9ish wide tires.that's the width of what im running,but you've got to make sure tire pressure is max to carry loads without a spacer between the duals.
looks like arrowcraft has what ya need with their magnum force adapters.
Adaptors, Wheels, Duality Fenders and Complete Kits - Arrowcraft :: Helping You Handle the Road for over 30 years!

there are a few different offset sizes that came on the trucks.your rims may have a greater offset than mine.i got mine from a 9th gen 2wd dually in a local yard.(Accuride 28511 with the lowest offset of 5.00)

 

I have a ser o 7 here in town,that fit 8 bolt with alignment pin. With tires. 1000$ they are steel, so I dont know the weight difference.

 

you will be PERFECTLY SAFE running 235.85/16 on your dually. 90% of the duallys out there run them Instead of the tiny 215s that originally came on the trucks.

245s on the other hand are pushing it. Actually any 75 series tire is pushing it

 

here is a pic with 235/85/16's on a 2wd 9th gen dually truck without wheel spacers between the duals.
this is empty.
(forget the tread.what you need to watch for is the sidewalls of course.)
what happens to tires when you put weight on them Brad?

if what you say is true,then 90% of dually owners are uneducated,are running wheel spacers or the c&c 4wd increased offset rims, or learned things the hard way.


Tire Tech Information - Dual Tires for Light Truck Use

 

Heres my motorhome, original rims, 215/85R16 tires at 65psi. These were my crappy old Hercules Load ranger D tires.

My new Michelin 10 ply load range E, with 75psi them have less bulge than this.

 

Wish i had a pic of 235s on a set of 2wd rims. There is 1/2-3/4" between the sidewalls when loaded w a pallet of seed corn(3200lbs).

That pic above is NOT 235s. I dont care what you say.
I have mounted more 235s on duallys then you have ever seen. THEY ARE SAFE