OT: Ranger Speedometer Correction

[supergrumpy]

picked up some very nice used tires and rims, tires are bigger and I know I will be traveling faster than the speedometer is now indicating

Is there a way to estimate how fast I need to keep speedo to travel at 55mph, my last resort is pacing a known accurate vehicle

FACTS:
2003 Ranger, V-6 automatic
original tires - 225/70-15
new tires - 235/75-15
rear end gears unknown

 

[rustyj]

Aww, just drop your speed on the speedometer by about 5 mph, and you should be ok.
I installed 875x16.5 tires on the rear of my motor home, to carry the weight better than 800x16.5's. It made my speed register lower than the regular tires did, so i just drove 50mph,in a 55 mph zone, and it worked out right. We have those speed checkers that the cops set along the roads, to tell you how fast you are going, and thats a great way to check your speedometer for accuracy!

 

[Harry Selleck]

Borrow someones GPS unit it will tell you exactly how fast you are going.
I use one on my PU all the time they work well

 

[Walt Davies]

If your state has those mile markers along the road like we do in Oregon you can go 60 MPH and it should take 60 seconds or one minute to go 1 mile. Then see how far off you are and set your speed accordingly. Or go to a shop that does speedometers and they can put in a new gear to correct you speedometer.
Walt

 

[RobMD]

supergrumpy:

Ironically enough, i've been using this today to figure out my Jeep speedometer.

You just enter your information and see what speed you're at.
CLICK HERE: speedometer recalibration calculator

 

[john *.?-!.* cub owner]

it will cost you a few dollars, but since your odometer is electronic, a dealer can easily set it for you.

 

[supergrumpy]

HEY, the police have that speed checker set up somewhere around here almost every day

thanks for the ideas