[ringpinion.biz]

who has actually checked their speedo accuracy after PPE calibration?

The reason I ask is Ive updated the PPE STD programmer like 4 times, and no matter what tire size I plug in, it has absolutely no effect on the speedometer reading. I've checked it with gps, and no matter what its always 10% (the tire size difference). I am convinced that the calibration feature just plain does nothing. Has anyone else expereinced this?

 

[Ogre1]

you're doin it wrong...

 

[ringpinion.biz]

how do ya figure

How do you figure? All other changes work. When the programmer is plugged back in it recognizes the tire size, etc. It just doesnt actually change the speedo reading. Tried it on several different tire sizes, several times, been on the phone with ppe several times. the truck is a 2001

you're doin it wrong...

 

[duroforshuro]

mine works fine when i adjust the tire size. almost exactly matches what the gps says

 

[la77chevy]

My PPE is doing the same crap. I adjusted my tire size to 32.5 and at 70mph I'm off by 4 mph according to the GPS.

 

[New to me GMC]

I could be mistaken but i believe there is an acceptable 3mph margin of error for a stock speedometer from the factory......

 

[68bowtie]

Mine still reads off by about 4 mph as well.

 

[rvjabo]

mine reads 1mph off @70 acording to my gps w/ stock tires

 

[RitzBlitz]

Mine is less than 1 mph off at 70 as well since I recalibrated it. I would call PPE to see what's up if you are sure you are doing it correctly.

 

[mxhead6.6]

with my edge cts..doesnt matter what tire size i pick as well..im always out 10+ Km/h...its stupid.. doesnt matter what i do it wont fix it.. it would say im doing 110-113 and doing a 100 says my gps..

 

[smoke660]

I just did mine a few weeks ago, and its dead on with the gps. Have you or the previous owner put in a new dash face? If so, if you dont get the needle back in the correct spot it could be off. Just a thought to chew on...