Inaccurate speedo in 2004 X

[DryDog]

I bought my wife a used 2004 Ed Bauer last night (10K miles on it.) Driving home from Ford I could see her dropping farther and farther behind me. When I got her on the cell I found she had the cruise set on 60, same as me.

The guage in my 91 is right on. When I take it back for warranty service what do you think they will find??

 

[Doug]

Might just need to be recalibrated. On most new vehicles the speedo is controlled by the ECU and is all electronic. No gears and no cables.

 

[Eneurb]

How far off was it??

 

[Doug904]

I bought my wife a used 2004 Ed Bauer last night (10K miles on it.) Driving home from Ford I could see her dropping farther and farther behind me. When I got her on the cell I found she had the cruise set on 60, same as me.

The guage in my 91 is right on. When I take it back for warranty service what do you think they will find??

You wouldn't beleive the wrong values I find in the PCM's when I'm reprogramming them! Everything from tire size values 20-40 rev's per mile off to actual gear size differences. Of course there is another module that the vehicle can use that will also hold the tire and gear size changes but to cover myself I always ask just to verify and then set it to read from the PCM values.

If you can send me your tire size, axle code from the white driver door sticker and the calibration code from the passenger's side door jam I can look at the calibration file in the PCM and tell you if it is off in the programming or atleast what it is set for from the factory.

Thanks, Doug.

 

[DryDog]

With cruise set at 60 she was actually doing about 57.

Tire size is P245/65R17, Axle code is 46, and Cal code I think is MVC1. It was a postage stamp white sticker inboard of the door hinges.
Thanks

Matt

 

[Eneurb]

3 MPH is acceptable as far as Ford is concerned. Speedometers can read up to 10% faster than actual vehicle speed to prevent manufactorer liability for speeding tickets.

 

[andylant2003]

I know that Honda and Toyota make it to where their speedometers are set a little on the fast side to help keep people dirving a little slower on the highways. I also think that Ford is doing it purposefully to their newer models for the same reason. My speedometer also runs about 3 mph faster then what I'm acctually doing.

 

[rwmorrisonjr]

1980's & early '90's GM cars were notorious for this, being as much as 5 mph faster than what you were going. My 2004's reads about 1-2 faster than what my GPS says.

 

[Doug904]

Hey guy,

I havent deserted you but rather I'm having to do a code request on your vehicle. I don't have your file in my database. I should have it very soon, possible by tomorrow, and then I'll post what your factory settings are.


Thanks, Doug.

 

[newtek007]

Tire size

I noticed that your tire size is P245/65R17. My stock tire size is P245/70R16. I don't know if they changed the size for your year but mine is a 2002 E.B. 4x4. See what you door states as the stock tire size. Might be worth a try.

 

[96limitedX]

the 03-up EBs had 17" wheels with 245/65 17s on them. i have detailed like 4 of them..all the same sized wheels/tires all 03-ups

 

[newtek007]

gottcha'

I figured the tire size probably changed. Just a thought. Oh well.

 

[Doug904]

Your Speedo should be very close. In your factory programming your Rev's Per Mile of the tires is set at 720 and with 245/65 R17's your actual Rev's per mile is 704 given everything is perfect as in air pressure and new tires. Also your gear ratio 46 is a 3:73 and this is what your present setting in the PCM is at.

Sorry it took so long, on alot of the newer Explorer's I have to put in a request and wait, it doesn't take a day or so.

Thanks, Doug.

 

[DryDog]

I really appreciate all of your responses, and the PCM info!

Matt