Too much grease in the speedometer cable?
For a couple of years, the speedometer cable in my 1984 S-10 Blazer squeaked. As it approached 100,000 miles, I finally took it to a Chevy dealer to get it greased. Then I began to notice that even though my speedometer was reading 15 mph over the speed limit, everyone was passing me, including little old ladies in second gear, and normally ticket happy highway patrolmen. I checked the speedometer against my wife's car on the highway one day, and found that the speedometer registers 5-10 mph faster than I'm actually going. When I took it back to the dealer, they said nothing they did could have made the speedometer read incorrectly. Could they be at fault? How do I get it fixed?
RAY: Well Carl, the dealership may, in fact, be responsible for the speedometer problem. If they put too much grease into the cable, some may have gotten into the speedometer head by accident. That could possibly cause an inaccurate reading.
TOM: But we hold you partially responsible too, Carl. After 100,000 miles and two years of squeaking, you were too cheap to spend a measly fifty bucks on a new speedometer cable. Now you're paying the price for being a cheapskate. Remember the Click and Clack Great Unyielding Truth: "It's the Stingy Person who Spends the Most."
RAY: Anyway, Carl, here's one way to tell if they put too much grease into cable. Wear white pants every day for the next six months. And when you get home at night, take a look at the pant legs below the knee. If you see drops of grease, that'll tell you the extra grease is slowly working its way out of the speedometer head.
TOM: Which means that in 5,000-10,000 miles, it'll be accurate again. Until then, just drive five or ten miles an hour over the speed limit. And when you get your first ticket, you'll know it's fixed.