Your tires would have be WAY off in size to give you that much error. If you are reading 100 KMH and actually doing 85 KMH it goes something like this.
Your car probably came new with 205/70-15" tires or something close. They turn 792 revolutions per mile and your car is calibrated for that. Just check tire-size sticker on the door pillar and compare to what you are actually using.
To get the kind of error you are reporting JUST from the wrong tires - you'd have tires spinning 931 turns per mile instead of 792. That would be pretty hard to do and I think you'd notice if your tires are that small? A 185/60 - 14" tire almost gets you off by that much at 914 turns per mile.
Unless you took some 13" tires off a Subaru and bolted them onto your Buick - I think your problem is elsewhere.
Without knowing the vehicle repair history - I'd suspect the wrong trans. drive gears, vehicle speed sensor, axle gears, etc. If you owned it when it was OK, and it all-of-a-sudden got wacky - then you've got a better handle on this than we outsiders do.
One example is my Dodge W250 diesel truck. It had always been off since I got it used and read 65 MPH on the speedo when actually going 56 MPH. Odometer was off the same. Speedo is electric. I finally discovered the wrong speedo-drive gearbox. It was probably changed long before I owned the truck. I bought a new gearbox with the correct ratio for $50 and now it's fine. For $65, I could of used an electronic corrector instead.
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]
Today's Featured Article - Talk of the Town: How to Remove a Broken Bolt - by Staff. Another neat discussion from the Tractor Talk Discussion Forum. The discussion started out with the following post: "I have an aluminum steering gear housing with a bolt broken off in it. The bolt is about a 3/8" x 1 1/2" bolt. I've already drilled the center of the bolt out with about 7/64" drill bit the entire length of the bolt. Only one end of the bolt is visible. I tried to use an easy out but it wasn't budging and I didn't want t
... [Read Article]
Latest Ad:
2022 John Deere 5045E, 4wd, front end loader and 3rd function with grapple. 120 hrs, 55k new, must sell
[More Ads]
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy
TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.
