how far off is the speedo wearing 37z?
tia
37z and speedometer
- ScubaSteve
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- Joined: Fri Jun 28, 2019 10:40 am
- Model Year: 2016
- Location: Kansas City, MO
Re: 37z and speedometer
I don't remember exactly, but its enough that its worth having it recalibrated. Not difficult at all if you get an OBDlink and AlfaOBD. No idea what the dealership would charge.
- Bill2014
- 1000_Posts
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- Model Year: 2014
- Location: Northern NY
Re: 37z and speedometer
Tire circumference is Pi times diameter.
Stock tires are approximately 33" in diameter and you are running 37's
So your actual speed will be 37/33 what is reading on the speedometer.
If you don't make a correction, when your speedometer reads 60mph you will actually be going 60x37/33 = 67.3mph
But you need to get your computer set for 37" tires to correct your shifting points...
Stock tires are approximately 33" in diameter and you are running 37's
So your actual speed will be 37/33 what is reading on the speedometer.
If you don't make a correction, when your speedometer reads 60mph you will actually be going 60x37/33 = 67.3mph
But you need to get your computer set for 37" tires to correct your shifting points...
2014 Power Wagon Laramie
Titan V5 2.5" Receiver Pintle Hook
Warn wireless winch controller
.188" DOM White Knuckle Rock Sliders
Locker Bypass & Nanny Kill Switch
Moab 2006
Titan V5 2.5" Receiver Pintle Hook
Warn wireless winch controller
.188" DOM White Knuckle Rock Sliders
Locker Bypass & Nanny Kill Switch
Moab 2006
Re: 37z and speedometer
Mine is about 7 MPH off, you really notice it on the down shift, or the 2 to 3 shift under minimal load. I will be getting a programmer soon. Just have not decided which one.
Re: 37z and speedometer
I just got the new and improved AEV Procal Snap. So far it’s working great.
2020 RAM Power Wagon
Level 2 equipment group, RokBlokz, BakFlip MX4, AEV Procal Snap
IG @ iowa_wagon
Level 2 equipment group, RokBlokz, BakFlip MX4, AEV Procal Snap
IG @ iowa_wagon