how much spedo dif with 31s

[sajnaj]

ok i jsut put 31's on my truck and i was wondering how much spedo dif there is am i go slower then it hink or faster any advice would be aprecited

 

[Sallad420]

I have 31's on mine, using the stock rims. And I believe at 100 kph (60mph) mine is out by about 10 kph, so if my speedo says 100, I'm really going 110. But at 50 I seem to out by less. So maybe the faster you go, the more it'll be out.

 

[airforcemook]

The larger size tires you go with the faster you'll be going per what the spedo says. Best way would either to get if adjusted (not sure the cost) or just drive 'with the flow' of traffic so as not to get a ticket...

 

[huskyfan23]

Mine was off 5mph going 35. I swapped in a digital speedo so now I can adjust for whatever size tires I use.

 

[airforcemook]

How much digital speedo cost and how was install?

 

[jrgaylor]

I have check my speedo with a GPS and after I got my 31's my speed was off 3 MPH at 70.

 

[sajnaj]

ok so its not that bad

 

[unclemeat]

What where the original tire size? An example 29" originial 31" new size 31/29=1.07.
Therefore your speed will be 1.07 x speedometer reading. At 60 mph on speedo the actual speed would be 1.07 x 60 = 64.2 mph.