Speedometer and mpg off

So I have had my 2019 sr5, dcsb, 4x4 tacoma for 4 months now. I have a couple of questions. My truck is completely stock. So the last few times I have filled up I have hand calculated my mpg and compared it to the dash read ou . It is always 1 mpg off. If my dash reads 23.5 the actual mpg for the tank will be 22.5. The next thing is it seems like my speedometer is off by 3 mph. If I am using google maps or Waze it will show my speed as 67 mph but my dash says 70 mph. What gives???? Any solutions to this or just deal with it? Thanks

 

I know that is a thing with the base model 5 lugs with the speedometer. I get about 28-29 highway, with my pump calulation so i cant imagine its better than that. so that leads me to believe that the problem is not related, or that the trucks have different issues. my truck reads more miles than it actually has on the odo, it could be argued that its set low so you dont get tickets, but it also could be to run the warranty out quicker.
As far as i know, you could find out what the system needs and get a appropriatly sized tire, but other than that deal with it. toyota says its normal

 

A guess is that the dash is calibrated a bit conservative to keep you from speeding. I was surprised that when I changed to an inch taller tire my GPS readings and dash were aligned.

 

Just about all vehicles from the factory will read faster than actual gps readings.

 

1 in bigger is what I've heard works

 

I'm assuming it's because they put different sized wheels on the different trim levels, but they just have one generic calibration that's within tolerance for all the variations... I don't know this, but it's logical enough to be true.

Also, you drive like my granny.

 

The OD of all the OME tires is about the same.

 

My computer MPG usually runs 0 to 2 MPG higher the hand calculation (trip odometer/gallons pumped). Doesn't seem to follow any set pattern given speed, distance or tank volume before fill up. A couple of times I set the trip to zero and set my Garmin to zero and after 300 miles there was only about a 1% difference in the two computed distances. My digital spedo and Garmin are usually within 1 MPH of each other.

 

The MPG readout is an estimate. I’ve never had it read accurately on any vehicle I’ve ever checked. It’s usually close or within reason.

As for the speedometer, Toyota’s acceptable range is usually about 2-4mph depending on the speed. It can vary with a lot of factors.

Have you checked the accuracy of your odometer? It’s always a good starting point if you suspect something as it is usually more accurate than the speedometer needle.

Jeff

 

Thanks for all the reply . Sounds like it is normal. Jeff how would one go about checking the odometer for accuracy?

 

There are occasionally odometer check sections on highways that will mark out 5 or so kms/miles which are a good way. Depends on your area I suppose if there are any. Otherwise you’ll probably just need to do it with mapping software or similar (the further the better obviously).

Jeff

 

You could download a speedometer app on your phone as I believe they use GPS and should be pretty accurate