I have an 06' F250 that I put a 4.5" lift and 35" tall tires on. I have contacted almost every dealer in AZ and they all tell me that they can't recalibrate the speedo for the larger tires. Is my only option an after market programmer?

 

They can definitley adjust the tire size through the computer, but there is a limit. I believe the lowest they can go is 600 revolutions per mile, Toyo says my 35x12.5R20 Open Comtry M/T take 592 revs per mile.

I'm not sure if my dealer updated my truck for the bigger tires or not, but my speedometer is within 1mph at 75mph according to my GPS. I think a lot of people that have checked there speedometer against GPS have found that the speedometer usually reads a little high coming from the factory. I would try to find a way to check your speedometer first, and then start calling dealers again if it is off. I'm sure one of the tech here might even be able to tell you the TSB for setting it or something like that so you can show the dealer how to do it.

 

Rickson Truck sells something to recalibrate, so it is possible. http://www.ricksontruck.com/speedometer.html

 

I am running Toyo A/T 325/60R20 which shows 591 revs per mile so we are almost the same. I have a friend with a GPS that I am going to check it with. Thanks for the great info. This was my first post here

 

If you do find that you need to adjust it there are a few ways to go about it. Like I said before you're dealer should be able to adjust it some, most of the aftermarket tuners will allow you to adjust it some, and there is also a product from superlift called the TruSpeed from Superlift that is pretty popular. I believe it will work with pretty much any size tire. Here is a link to the website for it.

http://www.superlift.com/accessories/truspeed.asp

Oh, and welcome to FTE. There is a lot of good information here and the guys are usually pretty helpful. Just try to stay away from topics like diesel vs gas, Amsoil oil, and aftermarket air intakes for a diesel engine they tend to get a little heated

Also, check out the tech sections at the top of most of the forums, there is a lot of great information there.

 

I have looked at the truespeed but when I called 4 wheel supply the told me they don't recommend them because they had to much trouble with them.

I was trying to avoid a tuner because the dealer claims that if they find out I have one it immediately voids the engine warranty. I really find that hard to believe but why take a chance. I have read alot of good stuff about the SCT programmer from LIPD but not sure I want to take the chance. I was also told that if anything happens to the engine the Ford rep will come and take a look and if he sees a pillar full of gauges he assumes it has been messed with and will deny engine warranty work.

 

I would probably try to get hold of Overkill or DC special from Truck Toyz Performance. They install a lot of lifts and can probably tell you a lot more about this than I can. I have never heard anyone complain about the truspeed, but I haven't read up on it a lot either.

I'm also avoiding tuners for now. My dealer is pretty mod friendly, and has no issue with my ram air, exhaust, or lift, but they wouldn't put a cat delete pipe in. I haven't asked them about tuners yet, because I am still breaking my truck in, but I doubt they will want me to run one. Theoretically you should be able to reset the PCM to the stock code and erase the memory by unhooking the battery before you take it to get worked on, but some feel that is unethical.

 

I only have 4500 miles on mine so far. Did you do a catback or turbo back exhaust? Do you have a dry air filter or an oil one?

 

I have the MBRP Pro Series 304 Stainless Turbo back kit with the stock cat (for now). The ram air hood I have works with the Airraid intake, so it is an oiled filter. I am going to check my intake when I change my oil and if I see too much dirt/oil I will probably start looking into doing something else but for now I like it. I don't know if you've figured it out yet but you can left click on a members name and it will give you a drop down menu. If you select view gallery you can see any pictures that member has uploaded to the site as well as any comments on them. I have a few in my gallery that show and list my modifications if you want to check them out.

 

I just called my local dealer on Monday to schedule an appointment to drop by and have them recal my speedo. They said runs about $86. I have the Hypertech tuner on my truck they just told me to set it back to factory until they recal and then set it back. The reason I am going to the dealer is my tuner does not recal the speedo for the 5.4L for some reason. Didn't know that at the time I bought it until I opened the box and began setting all of my own stuff.

 

I had the dealer reprogram my speedo for my 285's and I'm wondering if the PCM will go back to the default tire size if the battery is unhooked?

 

AZBUCK250, call Superduty Headquarters in Mesa and see what they recomend.

 

They recommend the Superchip programmer. They were one of the shops I called that didn't like the Truespeed, said it was to hard to calibrate and it kept failing.

 

There are few options for the owners to recal the speedos on the SD line of trucks. There are NO tuners that will recal the speedo since the ABS module feeds the speedo not the PCM. The dealers can recal trucks up to 35" tires after that you would need to use the Tru-Speed type convertor. I have heard for the newer trucks the dealers are locked out of being able to perform the recal.

I'm going to see what they say about my '06 so wish me luck. I have been told don't refer to it as "recaling the speedo", use the terms "recal the ABS" when discussing this with the dealers.

 

Good luck. All the dealers I have spoken to in AZ say they are locked out in 05 and 06 models. There are tuners that claim they adjust tire size to change the speedo. Not sure how they can do it but Ford dealers can't. I will have to try the re-cal the ABS and see what they say here.