Gear/Speed Mismatches for me

[ac97gt]

First of all, every one of those speed trap things that the police put up that show your speed read 5mph higher than my speedo does. Every one of them, exactly 5, no matter the speed. Also, I have clocked against friends and my speedo reads a consistent 4-6 higher than theirs. Now, my car doesn't pull (to me) like it has gears in it. I bought the car used and have no reason to believe that the gears are anything but the stock 3.27..

I know they are not anything 100% accurate to go by, but I found these numbers and my rpms do not match any speeds of the chart

I have the stock 17in rims, with 245/45R17 H rated tires.

On my speedo (that I believe reads 5 high), I redline 1st at 35mph, 2nd at 60mph, 3rd at 90mph, 4th at 120mph and 5th I don't know. Another rpm/speed combo that I remember about my car is that at 2000 rpm in 5th gear I am going 60mph via my *innacurate* speedo.

What gives?

[stanger9219]

Do you know how to check your gears? Well, if you dont here it is. Jack up your car, put it in neutral, Turn the back wheel around once and count how many times the driveshaft rotates. That number is what gears you have. I have 4.10's and do about 2600RPM@70. Never know, your speedometer just might be off.

[4.6LitreGT]

do what stanger said....but by the sounds of it, you got a problem besides different gears.

sounds like 3.55s or 3.73s 2000 rpms goin 60.

but if you had a different gear ratio...your speedo wouldnt be off exactly 5 mph all the time. it would be a off by a percentage.

like if you were going 10 mph it would read 12 mph
so if you were going roughly 50, your speedo would read 60.