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How far off is your speedometer?


David88

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Just for kicks.

I got pulled over doing what I thought was 55. Cop called another unit and he got in my truck and drove it at what the speedometer said was 55. Turns out, my speedometer reads off by 11mph. Explains why I almost run people over in the 35 mph zones.

He told me to just stick a gps in it and use the speed read out on it. It's what he did in his F150 instead of redoing the speedometer gears.
 


Earl43P

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Mine reads 7 mph faster than actual because I put smaller tires on it.

It's worth the plastic gear change in a case like yours.
 

getrdone52

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Mine reads about 3 mph slower than what I am going. I calculate it by using those speed reader things on the side of the road.
 

killj0y

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Just for kicks.

I got pulled over doing what I thought was 55. Cop called another unit and he got in my truck and drove it at what the speedometer said was 55. Turns out, my speedometer reads off by 11mph. Explains why I almost run people over in the 35 mph zones.

He told me to just stick a gps in it and use the speed read out on it. It's what he did in his F150 instead of redoing the speedometer gears.
That's about the same as mine. Got out of a ticket a few Weeks ago. Guess the cop understood what I meant, usually they just give me weird looks and issue a ticket.

I actually have a GPS to track it and I already know where the changes are. At 40 it's 5 slow, once you get to 55 it's 11 slow and after that out just dances around 11 and 13 slow. Sometimes I forget on the highway and I think man my 4 banger sucks cuz it feels like there's not much more power after 65/70....then I remember to add 10 to 13! And I slow down and look around for cops lol.
 

adsm08

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Mine is within acceptable calibration limits.

About 1.5 MPH at 55, as compared to my wife's Escape. Just calibrated it though.
 

Plum Ranger XLT

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Mine is 3 mph fast. Whenever I use my gps, it is always 3 mph slower than what my speedometer says.
 

alwaysFlOoReD

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My '97 f-150 speedo reads 100 and the gps reads 123 :icon_surprised:
OOOPs, I goofed, it's the other way around.
 
Last edited:

triumphrider-1

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My speedo reads fast by about 6%, and thats with larger than stock tires...
 

Mark_88

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I tested mine again the other day and it was between 8 to 10 Kph slow compared to my GPS. So I'm really going faster than my speedometer indicates even though I still have people crawling up on my a55 when I'm doing above the posted speed limit...

Now I know the world is going crazy...faster!
 

SeanWilson

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Just for kicks.

I got pulled over doing what I thought was 55. Cop called another unit and he got in my truck and drove it at what the speedometer said was 55. Turns out, my speedometer reads off by 11mph. Explains why I almost run people over in the 35 mph zones.

i can NOT believe that the cop got in a drove it, to see if what you said was true!! they just give me tickets and say fix your issue
 

BLOODBANE

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My Ranger is almost dead on, but I have replaced the speedo gear in the T-case (D20). My Explorer and Samurai reads 5mph faster than what your actually doing. I don't worry about calibrating those 2, I just adjust my speed accordingly.
 

Ford78

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Mine reads 15mph faster than what I'm doing.
 

doorgunner

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I bought an Classic speedometer (electric driven) when I did the body swap...

it's right-on at any speed....

Mark88---I haven;t checked it with my GPS at 240 kph yet ......

;missingteeth;
 

Zeisan

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Mine is incrementally slow by 1mph per 10mph i.e. at 50mph I'm actually going 55mph. That's due to having 235/75r15ATs on a 225/70r15 truck. Haven't gotten round to getting it fixed.
 

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