Has anyone noticed there speedometer reading 3-4 mph faster than actual speed. I compared my speed to a GPS and to the Test Mode Listed in one of the threads below and it appears that the gauge reads faster than actual. Wondering if there is a fix to this and if it is widespread.

Jimmy

2004 SCAB Fx4
True Blue

 

DOT spec for speedometer error is +/- 7%. So if you are going 55 mph the speedometer can be as much as 3.85 mph off in either direction. This is considered normal.

Also keep in mind that handheld GPS units are not always 100% accurate when it comes to speed.

 

Yep, I started the other thread... and just to add to this one... Mine measures EXACTLY 2 MPH higher than the actual vehicle speed.

 

In this day of technology, there is no reason for speedo error with these electronic speedometers but there is. Most speedo's read too fast any yes the mfgr's say that up to 10% off is ok but if the speedo reads fast by 10% you're mileage is going up by 10% and you go out of warranty on the mileage faster. Please tell me if my reasoning is wrong.

 

Actually, my speedo reads fast, but my mileage is perfect....

Either that or our '04 QUest, '97 Taurus, and '96 contour are all exactly the same amount wrong.

 

A previous F150 of mine ('97) had a 12% speedo error...an indicated 62 mph was actually 55 mph. Likewise, the odometer was off. My concern was that when indicating 36,000 miles (i.e. warranty expiration), I really had only 31,680 miles on the truck. I notified Regional Ford in writing to document the issue to protect myself in case of a failure under warranty. They offered to fix the problem, but could not assure me that a dash removal to correct the problem could not be done without causing additional problems.

 

My speedo is off, too. 3-4 MPH at highway speeds. Has anyone attempted to have this fixed by Ford? Any luck?

 

Does anyone know if the odometer calculates from the test mode speed? The Test Mode Speed is approx 4 mph less on mine when the Speedo is reading 50 mph. Until I found this out I always thought I was speeding. Beside this issue my truck has been completely flawless.

Jimmy

 

I was driving through a construction zone yesterday and it had one of those stationary speed signs that tell you how fast you are going in the 45 mph zone. I was going 60 on the speedometer and the radar sign said 59. I have to drive through there again today and I'll check it again.

 

I also drove through a construction zone with a meter.
My speed was 60 on spedo. and 60 on the meter.
+or- 7% and 10% is ridiculous. Almost all electronic
gauges are +or- 2%.

 

The error is usualy intentionaly done by the Maker to try and reduce the insurance rates.

For instace my STi is off 5mph from approx 30 actual on up. There is also a slight linearity error so at the 147mph actual speed limiter its showing 153 indicated. Below 30 actual it reduces the intentional error so you don't get a nasty pause in the speedo, or being showing 10mph while at a fast walking pace.

 

...and that would reduce insurance how?

Then, people are going to realize their speedometer is off, and in 55 zones go what looks like 60 on their speedometer to keep up with traffic.

I would much better know that I am truly going 70-75 in a 70MPH zone than wondering why I'm having to go (what looks like on my speedometer) 80MPH to keep up with traffic. I like keeping up and not feeling like I'm excessively speeding.

I plan on asking my dealership about this when my oil change comes, but I'm not worrying about it until then.

 

My speedometer is off by about 3 MPH too. At 75 MPH on the speedometer, my handheld GPS showed 72 MPH. It probably is farther off the faster I go. I had a buddy following me in a GMC who also had a GPS and his was spot on.

 

My Uniden GPSRD Radar Detector with GPS shows the speedometer on my 04 FX4 to be about 2-3 mph fast, as the others with GPS have said. With the cruise set on 60, the GPS shows 57-58.......

 

that is why when I put the bigger tires on my truck and took it too the dealer to recalibrate the speedometer the dealer told me my speedometer was not off enough to mess with. and sure enough I checked my speed not with a gps but by useing a speedometer check mile markers on the side of the highway. and my speedometer seems to me off by less than 1 mph at 60 mph. so if you want to fix your speedometer reading why not slap a set of 33" tires on. of coarse if my odometer is differant from my speedometer then it will be off. maybe that is why my gas mileage calculations have not been as good as I have hoped for.