Can't seem to get correct tire size with AlphaOBD.

[spywiz]

I have BFG 285/65 R20 K02 tires on my 2019 1500 Limited. I have changed the "Program Tire" size to 2760mm. Also every other size from 10mm up and down. My measurement of the tire is 2761mm. Does anyone have this same tire that can give me an idea of what to put in AlphaOBD? Thanks for any help.

 

[HSKR R/T]

I have BFG 285/65 R20 K02 tires on my 2019 1500 Limited. I have changed the "Program Tire" size to 2760mm. Also every other size from 10mm up and down. My measurement of the tire is 2761mm. Does anyone have this same tire that can give me an idea of what to put in AlphaOBD? Thanks for any help.

Best bet is to make a change and see how it effects the speedo and go until you hit the magic number.

 

[frisby5]

I have BFG 285/65 R20 K02 tires on my 2019 1500 Limited. I have changed the "Program Tire" size to 2760mm. Also every other size from 10mm up and down. My measurement of the tire is 2761mm. Does anyone have this same tire that can give me an idea of what to put in AlphaOBD? Thanks for any help.

I have 275 65 20 general grabbers tires , i had mine at 2718 ,i was two mph lower than the speedo. I still need to adjust again. But you have to remember the tires sit lower in the front with the weight of the truck on them so your measurement is going to be a little lower.

 

[HSKR R/T]

I have 275 65 20 general grabbers tires , i had mine at 2718 ,i was two mph lower than the speedo. I still need to adjust again. But you have to remember the tires sit lower in the front with the weight of the truck on them so your measurement is going to be a little lower.

That all depends on your tire pressure. You should be running higher pressure in the front for the exact reason you just stated.

 

[HookedonRam]

I have BFG 275/65R20s so what is the setting supposed to be when I do decide to change it in the AlphaOBD?

 

[spywiz]

I ended up going with 2631mm. It is dead on on the speedometer. My tires are BFG 285/65R20 A02. with 35 psi.

 

[frisby5]

Mp

I ended up going with 2631mm. It is dead on on the speedometer. My tires are BFG 285/65R20 A02. with 35 psi.

I will try that setting to see if it works for me .

 

[Idahoktm]

I ended up going with 2631mm. It is dead on on the speedometer. My tires are BFG 285/65R20 A02. with 35 psi.

That can't be right. I used 2625mm's for my 305/55R20 Ridge Grapplers. Your tires are 1.4" taller than mine, so it should be closer to 2730mm's.