Actually, anyone in the aftermarket tuning industry should have known better than to say that - or there was a misunderstanding in the communication.
I'll tell you how it *really* works...........
The actual *truth* to this is that there are TWO areas in which this is controlled in the PCM in the 1999 & newer F-150 - one is the VID block, which is where Ford does it (this is the areas that is active and that controls your speedo calibration from the factory), and then the other is the area is inactive unless and until a tuners in the aftermarket, like us for example, recalibrates the speedometer - Ford themselves does NOT use this second areas I am talking about, but they do have to enter A value. So they put in a common value that reflects a gear ratio & tire size that was available on that vehicle - now it may or may not be the gear ratio for that *individual* vehicle, as there are numerous different gear ratios & tire sizes available, so they have to put something in there - this is extremely basic.
Now the area that tuners in the aftermarket recalibrate the speedometer in is NOT used AT ALL FOR ANYTHING UNLESS there is a specific SWITCH turned off in the PCM's programming - which only happens when using an aftermarket tuner or chip!!
Trying to say that Ford has an incorrect gear ratio programmed in and trying to blame it on that is pure bunk - anyone with a brain in the tuning industry knows that these vehicles have different gear ratios available from the factory, especially trucks like the F-150 - and *something* has to be put in there for a value, and that value is in fact good for ONE of the gear ratios available. If it didn't work like this, meaning if that area was active under any condition OTHER than when using an aftermarket tuner and altering it, then you would have gotten a constant code, a 1635 "Axle/Tire Out of Range" code from Day 1 of that vehicle's existence!
See, when a tuner *correctly* alters the tire size, you must ALSO put in the correct gear ratio, too (of if they want to alter the gear ratio, they must also enter the correct tire size info, too) - you cannot just put in the tire size alone, and *that* is what the problem was - not Ford putting in incorrect information - the info in the area that tuners can access is NOT USED by Ford - they use the VID block, so it doesn't matter what is in the other area unless you plug in an aftermarket tuner - and IF you do *that*, then you MUST plug in not only the correct tire size info, but you must also make sure to enter the actual gear ratio on the vehicle.
That was a cheap shot trying to blame Ford for this, IMHO - anyone who knows anything about vehicles in general knows that they are offered with numerous different gear ratios from the factory, and also knows that there are two different areas this info is stored in, and that only ONE of them can be used at a time - they can never both be used at the same time - this couldn't get more basic.
The fact that Ford gives us that second area is doing us a FAVOR so that we CAN alter this in the aftermarket, as the VID block can only be altered to gears & ties that Ford offered on that vehicle from the factory.
So in this second areas that Ford gives us where we can enter a much wider range of gear ratios & tire sizes that is NOT used until it is activated by an aftermarket tuner or chip has to have *something* entered there as a value - for example, in all 2004 & newer 5.4 3V F-150's 3.73 is entered for the gear ratio there regardless of it's actual ratio - once again, that area is NOT USED UNLESS you plug in an AFTERMARKET tuner - and anyone involved in this industry should immediately know that you have to enter both the correct tire size AND the correct gear ratio if you want to make a a change to EITHER the tire size or the gear ratio - this is extremely basic.
So either there was a very bad misunderstanding in that communication (and I do not believe that as that post was written), or whoever it was from Edge simply didn't know what they were talking about, as this is so basic on FoMoCo vehicles that virtually any tuner knows this (and certainly anyone working for a tuning manufacturer certainly should have known), trust me.
Mind you, this is not meant as an attack on Edge, rather an explanation as to how this actually works, and the fact that anyone in this industry should have known this - this is not something that most vehicle owners generally know, but anyone in this industry certianly should know.
Edge reveals the truth!
I knew it was a bunch of crap and this is probably why. I fixed it by putting on larger tires and now it reads correctly. Thanks Ford.
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