where can i get a gear to underdrive the speedo about 4 miles less?87 toy truck 2wd std trans
speedo faster han actual speed,87 Toyota truck...
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And the faster you go the farther off it is.
You can probably fit a slightly taller tire on it....that'll fix it.
Bigger is better for me anyway.
Bigger is better for me anyway.
Both of my Lexus' read 2mph higher than my GPS. In my experience most luxury brands, have a higher difference in actual speed vs speedo speed. Also, in my experience Ford's have been most accurate with their speedo's.
They do that on purpose, I believe one of the reasons is already listed above.
They do that on purpose, I believe one of the reasons is already listed above.
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And this brings up a warranty issue. The odometer is reading more miles over time than you actually drive. In 25,000 miles, your odometer would read about 26,000 miles with a 4% error. So by the time your odometer read 36,000 miles, you would only have done 34,600 miles and get cheated out of about 1400 miles of warranty coverage. If I remember, Nissan was involved in some law suits over this.
Originally Posted By: Boomer
And this brings up a warranty issue. The odometer is reading more miles over time than you actually drive. In 25,000 miles, your odometer would read about 26,000 miles with a 4% error. So by the time your odometer read 36,000 miles, you would only have done 34,600 miles and get cheated out of about 1400 miles of warranty coverage. If I remember, Nissan was involved in some law suits over this.
FWIW, I thought that all odometers were calibrated to be accurate, but the ECU raised the speedometer by a certain percentage. They both get their readings from the same speed sensor, I believe.
And this brings up a warranty issue. The odometer is reading more miles over time than you actually drive. In 25,000 miles, your odometer would read about 26,000 miles with a 4% error. So by the time your odometer read 36,000 miles, you would only have done 34,600 miles and get cheated out of about 1400 miles of warranty coverage. If I remember, Nissan was involved in some law suits over this.
FWIW, I thought that all odometers were calibrated to be accurate, but the ECU raised the speedometer by a certain percentage. They both get their readings from the same speed sensor, I believe.
Originally Posted By: hypervish
Also, in my experience Ford's have been most accurate with their speedo's.
Really? I've found Ford's to be the most far-off. Trucks, mainly. Pass one of those roadside radar-signs and the speedometer will be off by as much as 5 MPH, always higher than what the sign says. Go by the same sign in almost any other vehicle, and its much closer, usually within 1 or 2 MPH. Stock tires all around.
Also, in my experience Ford's have been most accurate with their speedo's.
Really? I've found Ford's to be the most far-off. Trucks, mainly. Pass one of those roadside radar-signs and the speedometer will be off by as much as 5 MPH, always higher than what the sign says. Go by the same sign in almost any other vehicle, and its much closer, usually within 1 or 2 MPH. Stock tires all around.
Originally Posted By: Klutch9
FWIW, I thought that all odometers were calibrated to be accurate, but the ECU raised the speedometer by a certain percentage. They both get their readings from the same speed sensor, I believe.
Yup. Odo is more or less accurate. Speed is inaccurate because the computer deliberately increases the value read from the sensor before it delivers it to the speedo. At least that's how it's done on modern vehicles. Not sure this applies to the OP's '87 Toyota.
FWIW, I thought that all odometers were calibrated to be accurate, but the ECU raised the speedometer by a certain percentage. They both get their readings from the same speed sensor, I believe.
Yup. Odo is more or less accurate. Speed is inaccurate because the computer deliberately increases the value read from the sensor before it delivers it to the speedo. At least that's how it's done on modern vehicles. Not sure this applies to the OP's '87 Toyota.
Originally Posted By: Boomer
And this brings up a warranty issue. The odometer is reading more miles over time than you actually drive. In 25,000 miles, your odometer would read about 26,000 miles with a 4% error. So by the time your odometer read 36,000 miles, you would only have done 34,600 miles and get cheated out of about 1400 miles of warranty coverage. If I remember, Nissan was involved in some law suits over this.
Honda had the same issue, my last (2004) CR-V had a bulletin that stated Honda would extend the warranty to 37,500 miles because the odometer was reading high.
And this brings up a warranty issue. The odometer is reading more miles over time than you actually drive. In 25,000 miles, your odometer would read about 26,000 miles with a 4% error. So by the time your odometer read 36,000 miles, you would only have done 34,600 miles and get cheated out of about 1400 miles of warranty coverage. If I remember, Nissan was involved in some law suits over this.
Honda had the same issue, my last (2004) CR-V had a bulletin that stated Honda would extend the warranty to 37,500 miles because the odometer was reading high.
Ever since I discovered that my Toyota Camry's speedometer was off by a programmed 3 MPH, I've tested every vehicle I've driven with a speedometer app on my Android phone. Both of our Honda vehicles are pretty much dead accurate. If it reads 35 MPH, you're going 35 MPH. Same for our former '07 Chrysler and the '06 Dodge we have at work. The '06 F-150 that I drive at work reads 1-2 MPH high, as do the two Fusion Hybrids and the '05 Ford Taurus. They're a consistent 1-2 MPH at all speeds (not a percentage), so I'm sure it's programmed in the cluster or PCM.
Originally Posted By: css9450
Originally Posted By: hypervish
Also, in my experience Ford's have been most accurate with their speedo's.
Really? I've found Ford's to be the most far-off. Trucks, mainly. Pass one of those roadside radar-signs and the speedometer will be off by as much as 5 MPH, always higher than what the sign says. Go by the same sign in almost any other vehicle, and its much closer, usually within 1 or 2 MPH. Stock tires all around.
Same here. EVERY Ford I've ever owned since the early 80's - the speedometer reads higher than actual speed. I just got back from a 2700 mile trip in the Mercury, and the road side and permanent mounted radar units (Northern Ca and Southern Oregon have signs with radar units on sharp curves in the mountains) as well as my GPS, has verified a 1 - 2 MPH difference at all speeds from 25 MPH to about 80 MPH.
The speedometer in the wife's Camry is about 3 MPH fast. Always had been since it was new. The Trailblazer was always right on the money. At least GM did that right!
Originally Posted By: hypervish
Also, in my experience Ford's have been most accurate with their speedo's.
Really? I've found Ford's to be the most far-off. Trucks, mainly. Pass one of those roadside radar-signs and the speedometer will be off by as much as 5 MPH, always higher than what the sign says. Go by the same sign in almost any other vehicle, and its much closer, usually within 1 or 2 MPH. Stock tires all around.
Same here. EVERY Ford I've ever owned since the early 80's - the speedometer reads higher than actual speed. I just got back from a 2700 mile trip in the Mercury, and the road side and permanent mounted radar units (Northern Ca and Southern Oregon have signs with radar units on sharp curves in the mountains) as well as my GPS, has verified a 1 - 2 MPH difference at all speeds from 25 MPH to about 80 MPH.
The speedometer in the wife's Camry is about 3 MPH fast. Always had been since it was new. The Trailblazer was always right on the money. At least GM did that right!
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BMW is clearly the worst when it comes to speedo accuracy.
Honda was involved in a lawsuit over it and was forced to extend the warranty by some number of miles a few years back, if I remember right.
The American cars seem to be much better here, for whatever reason.
Honda was involved in a lawsuit over it and was forced to extend the warranty by some number of miles a few years back, if I remember right.
The American cars seem to be much better here, for whatever reason.
I've checked the speedo of my '02 Explorer against those road side speed checkers and my GPS. And it dead on the money.It just takes the GPS a few seconds longer to stabilise.,,
What I found out on my 01 toyota tundra is that the speedometer analog gauge is 3 MPH off vs. the MPH reading on a scan tool. I tested the scantool MPH data against GPS and those roadside speed checkers and it's accurate to about 1 MPH.
Originally Posted By: daves66nova
where can i get a gear to underdrive the speedo about 4 miles less?87 toy truck 2wd std trans
probably not what you want to hear but I'd just ignore it.. if you know its that far off just adjust your driving.
or next time you buy tires step up one size should fix that.
ie 215/70r15 to 225/75r15 or similar
also it would be a percentage difference not a mph difference
for example you said its 4mph off... at what speed?
if its at 85 thats alot different than at 45mph
(5% off vs 10% off)
find a nice flat piece of road and use a smartphone speedometer app or gps to see aprox how far its off at 60mph or so. then you will know the percentage its wrong by.
where can i get a gear to underdrive the speedo about 4 miles less?87 toy truck 2wd std trans
probably not what you want to hear but I'd just ignore it.. if you know its that far off just adjust your driving.
or next time you buy tires step up one size should fix that.
ie 215/70r15 to 225/75r15 or similar
also it would be a percentage difference not a mph difference
for example you said its 4mph off... at what speed?
if its at 85 thats alot different than at 45mph
(5% off vs 10% off)
find a nice flat piece of road and use a smartphone speedometer app or gps to see aprox how far its off at 60mph or so. then you will know the percentage its wrong by.
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Originally Posted By: Rand
Originally Posted By: daves66nova
where can i get a gear to underdrive the speedo about 4 miles less?87 toy truck 2wd std trans
for example you said its 4mph off... at what speed?
(5% off vs 10% off)
find a nice flat piece of road and use a smartphone speedometer app or gps to see aprox how far its off at 60mph or so. then you will know the percentage its wrong by.
Yeah, i did this already. It's off around 4mph at 60-65mph
Originally Posted By: daves66nova
where can i get a gear to underdrive the speedo about 4 miles less?87 toy truck 2wd std trans
for example you said its 4mph off... at what speed?
(5% off vs 10% off)
find a nice flat piece of road and use a smartphone speedometer app or gps to see aprox how far its off at 60mph or so. then you will know the percentage its wrong by.
Yeah, i did this already. It's off around 4mph at 60-65mph
In my experience, the speedometer is not always off by a percentage, but by a set number. For both of my Fords, it seems to be in the neighborhood of 1.5-2 mph (based on speed sensors and GPS). This variance applies when going 25 mph or 70 mph; it's still off by the same amount. I think this way is actually a better idea, and helps reduce speeding even more. Take 25 mph for example. At a 4% increase, the speedo would read at 26 mph. Most small speedometers, depending on spacing, might not even register that to the human eye, especially if someone takes only a quick glance at it. I'd prefer my speedometer already read a set amount higher, that way I know I can go "47" in a 45 zone, subtract 2, and know I'm safe. I'd rather not have to calculate a percentage in my head for any given speed I happen to be going. This would lead to massive inattention to the road and lots of crashes
Originally Posted By: Klutch9
In my experience, the speedometer is not always off by a percentage, but by a set number. For both of my Fords, it seems to be in the neighborhood of 1.5-2 mph .
With our Rangers (we have a fleet of them here at work), they're all off by 5 MPH.
I wonder: Perhaps they calibrate them for a certain size tire & wheel, and if you buy a model with any other size than what the calibration is based on, you get the speedometer error? Ours are all base models with stock tires. No 4x4s.
In my experience, the speedometer is not always off by a percentage, but by a set number. For both of my Fords, it seems to be in the neighborhood of 1.5-2 mph .
With our Rangers (we have a fleet of them here at work), they're all off by 5 MPH.
I wonder: Perhaps they calibrate them for a certain size tire & wheel, and if you buy a model with any other size than what the calibration is based on, you get the speedometer error? Ours are all base models with stock tires. No 4x4s.
My Cruze actually reads ~.7mph slow, according to my GPS. My grandmothers edge reads 5mph fast.
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