Okay guys i have a question concerning my new tires that im gonna get. I have 17" factory wheels and i'm getting 22" ers what size tire should i get that won't throw off me speedo. I like the nitto tires and the toyo tires if thats any help.

 

What would have really helped, is if you had indicated the actual size spec for the 17" tires, but perhaps you didn't know. Rams with factory 17s had either 245/70-17 or 265/70-17.

If your original tires are 245/70-17, the overall inflated diameter is about 30.3" I'm not aware of a 22" tire that comes close to that overall diameter.

If your original tires are 265/70-17, the overall inflated diameter is about 31.5". The closest 22" tire size for that diameter would be a 305/40-22, which as an overall inflated diameter of about 31.6"

 

I really hope you're not looking to do any serious off-pavement adventuring with 22" rims and 30 or 31.5" tires. This combination on a 4x4 truck will create a hard buck-board ride and the sidewall of the tire will have no flex for climbing over rocks or even small pebbles in the trail. Be prepared for bent rims and blown beads. Worst case is maybe a broken axle or two.

2003 Dodge Ram 2500 4x4 Hemi Laramie Sport

 

you'd be crazy to think that i would take 22" rims off-road. Hell i don't take my truck off road at all. I don't even put anything in the bed. My truck is for all show and go. Lookin nice while speeding down the road.

 

Go to tirerack.com and pull up the specs on the tires. Find 22's that have an aspect ratio small enough to make the overall diameter of the tire match you 17's.
That's all you need to kep the speedo happy. Also compare how many revolutions per mile the tires make. Same thing as tire diameter basically.

 

ORRRR...

you can throw on what ever size you want...

take the old size on paper and the new size on the truck... Take both to the Dealership and ask them to reset your computer... should do it for a small fee.. and you can get what ever size rubber you want on those beautiful 22's

Dano

 

CORRECTED

((((WIDTH*(RATIO/100)/25.4)*2)+DIAMETER))
275/75R70= ((((275*(70/100)/25.4)*2)+17))=32.1575

Here is the formula for determining tire size. Also the dearler here in Omaha charges $90 to flash the computer.

 

That works or - (width/25.4*aspect ratio)*2+rim width=O.D.

285/25.4*70%=7.85*2+17=32.7

That is for a 285/75R17, tire racks chart for a BFG is 32.8", so the formula is pretty close.

Ramit, check your math or original tire size-not sure what a 285/75R70 is but a 285 70or 75 R17 is bigger than 32.15

 

Your Right i had the example as 285(which I have) and put in the value for the 275.
Here are the sizes that dodge puts on the truck. Not to be nickpicking, your formula is not a true algebra form. We have the same info but mine will plug right into a spreadsheet. BUt great catch, old age stinks hahahah

245 70 17 30.5039
265 70 17 31.6063
275 70 17 32.1575
285 70 17 32.7087
275 60 20 32.9921
305 40 22 31.6063