Speedometer reading too fast?

Arktikos

Explorer
Just bought a 2001 4 Runner to replace my pickup truck. The tires are 225/75r/16, which I believe is stock for SR5. But it seems like I'm not actually going 60 when the speedo says 60, I'm going slower.
Is it possible that this truck is geared for a slightly bigger tire?
 

4runnerteq

Explorer
225 was the original standard size. However most if not all 4wd were changed to 265/70 at the port. However, its not unusual for a Toyota to register 3 to 4 miles per hr faster on the speed than actual speed. Going to a 265 may get it closer.
 

zelatore

Explorer
While I can't speak to Toyota in particular every vehicle I've owned read somewhat fast from new.

Just in the current stable we have
'07 Land Rover LR3
'14 Chevy Traverse (don't blame me, wife's company car)
'13 Nissan NV200
'06 Triumph Speed Triple

All have varying degrees of optimistic spedometers.

Past vehicles have included BMW, Audi, Saab, Ford, Dodge, Honda, and even lone Toyota she had before we got together. All were optimistic to some degree when stock.
 

1stDeuce

Explorer
NHTSA regulations basically say that its OK for the speedo to read a little fast but that it may NOT read slow. Most mfgs err on the fast side to ensure compliance. Either GPS it (smart phone app) or time 10 miles on the freeway at 60 and see if it takes 10 minutes. :)
 

fjtoyman

New member
If you check the sticker on the door post, it will tell you thenun original tire size. From there you can judge if you should go back to original. Some Sr5's had 31x10.50's as original, in that case you would definitely be going slower than your speedo with 225's mounted.

Sent from my HTC One_M8 using Tapatalk
 

ChrisWH

New member
If you check the sticker on the door post, it will tell you thenun original tire size. From there you can judge if you should go back to original. Some Sr5's had 31x10.50's as original, in that case you would definitely be going slower than your speedo with 225's mounted.

Sent from my HTC One_M8 using Tapatalk

What's funny is that my 2000 Tacoma door sticker says 225, but it came with 265 (an optional tire size). The previous owner had put 225s on it when they got new tires, and then the speedo read 10 mph high at 65 mph. I put the original tire size back on, and now the speedo is only 4 mph high at 65.

Anyway, to the OP, you can check to see if 265 was an option tire for the year of your truck. In addition, you can look at your spare tire to see if it's the original...
 

fjtoyman

New member
The tire size on the sticker may give you a clue as to the stock differential ratio. They should match. If you put a smaller tire on than the sticker says, you will be going slower than your speedo says.

Sent from my HTC One_M8 using Tapatalk
 

Arktikos

Explorer
Sticker says 225 by 15", but the wheels are actually 16x7 JJ, 5 spoke design 4 Runner aluminum rims. They appear to be original. Good idea to check spare tire. Will do.
 

Arktikos

Explorer
If you check the sticker on the door post, it will tell you thenun original tire size. From there you can judge if you should go back to original. Some Sr5's had 31x10.50's as original, in that case you would definitely be going slower than your speedo with 225's mounted.

Sent from my HTC One_M8 using Tapatalk

I checked the spare tire and it is an original, sized at 265/70r16. Tag on door is not accurate, for some reason. Wrong wheel size, wrong tire size. PO bought tires based on faulty tag info, explaining speed/speedometer discrepancy. Thanks to ChrisWH for his suggestion.
 

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