Bumper stickers on many trucks state “How’s My Driving?” and then give a phone number for other motorists to call and report poor drivers. “How’s my driving” bumper stickers have been cited in print since at least 1986 and were started as a safety measure. Some “How’s My Driving?” stickers have been placed on vehicles with teen motorists to promote safe driving among new drivers.
The “How’s My Driving?” stickers have been the subject of parody since at least 1987, when the phone number given encouraged other motorists to call “1-800-EAT-SHIT.” “How’s My Running? Call 1-800-EAT-DUST” has been printed on the back of runners’ T-shirts since the 1990s.
Wikipedia: “How’s my driving?” sign
A how’s my driving sign (or “how is my driving” or similar) is a decal posted or painted on a back of a fleet vehicle or other vehicle operated by an employee driver. The decal usually has a phone number or website address and other identifying information so that the public can call and report on the behavior of the vehicle’s driver. Depending on the company, the phone number or website is monitored by the vehicle’s owner or by a 3rd party company.
Similar programs have also been implemented for vehicles driven by teenagers in hopes of improving the safety of teenage drivers and with drunk drivers. Use of “How’s My Driving” regimes for other systems than traffic have been discussed, also in relation to eBay and Wikipedia.
Google News Archive
14 October 1986, Miami (FL) News, “Hot line targets bad truck drivers,” pg. 2A, col. 2:
Motorists tired of being terrorized on the road by reckless truck drivers soon will have the means to help curb the worst offenders, the Florida Trucking Association announced yesterday. The group is urging people to report bad drivers and get them off the road so they won’t give good truck drivers a bad name, said Earl Joyner, chairman of the board of the association, The association, which represents se about 1,000 trucking companies, has provided signs to its members that read, “How’s My Driving?” along with a toll-free number, 1-800-345-SEMI, which are placed on the back of the trucks so motorists who think the rules of the road have been abused can report bad truck drivers. The hot line is already operating.
6 August 1987, The Times-Piacyune (New Orleans, LA), “Safety program works, Kenner officials say” by Kim Chatelain, pg. B-2, col. 4:
Bumper stickers reading, “How’s My Driving” and a City Hall telephone number are on most city vehicles.
1 October 1987, Mobile (AL) Register, “Legal questions derail bumper sticker control,” pg. 19-A, col. 2:
MONTGOMERY, Ala. (AP)—A new state law designed to remove obscene bumper stickers from Alabama highways has been run off the road by legal questions.
The lawsuit, filed in U.S. District Court on Monday, was brought by Wayne Baker of Cottondale, who was stopped by Trooper Lamar Glover south of Dothan recently for sporting a sticker on his rig that read “How’s My Driving? Call 1-800-EAT-....”
13 September 1991, Atlanta (GA) Journal-Constitution, “More than a game, it’s...our way of life vs. theirs” by Lewis Grizzard, pg. A1:
And Hosea Williams has a bumper sticker on the back of his car that says, “How’s my Driving? Call 1-800-EAT-DUST.
OCLC WorldCat record
How’s My Driving?
Author: Gary Stix
Publication: Scientific American, v265 n4 (199110): 124-124
8 April 1994, Washington (DC) Times, “Sign of the times”:
“How’s My Driving?” bumper stickers have become commonplace. They’re on commercial trucks everywhere, with 800 numbers that allow fellow motorists to report the driving habits of company drivers.
OCLC WorldCat record
How’s my driving? : staying safe behind the wheel : shifting gears in later years.
Author: Oregon. Driver and Motor Vehicle Services.
Publisher: Salem, OR : Oregon Dept. of Transportation Driver and Motor Vehicle Services, Driver Safety Unit, 
Edition/Format: Book : State or province government publication : English
OCLC WorldCat record
How’s my driving? : why every other driver doesn’t seem to have a clue!
Author: Steve Dziadik
Publisher: Denver, Colo. : Outskirts Press, Inc., 2009
Edition/Format:Book : English
Word Mark HOWSMYDRIVING.COM
Goods and Services IC 045. US 100 101. G & S: Providing information regarding safe and unsafe driving, namely, receiving reports on safe and unsafe driving via the Internet and relaying the reports to vehicle owners. FIRST USE: 20010301. FIRST USE IN COMMERCE: 20010301
Mark Drawing Code (5) WORDS, LETTERS, AND/OR NUMBERS IN STYLIZED FORM
Trademark Search Facility Classification Code NOTATION-SYMBOLS Notation Symbols such as Non-Latin characters,punctuation and mathematical signs,zodiac signs,prescription marks
Serial Number 77528727
Filing Date July 22, 2008
Current Basis 1A
Original Filing Basis 1A
Published for Opposition June 23, 2009
Registration Number 3678550
Registration Date September 8, 2009
Owner (REGISTRANT) Drive4Life, LLC LIMITED LIABILITY COMPANY UTAH 1767 Auburn Ridge Ln. Draper UTAH 84020
Attorney of Record Kenneth C. Booth
Prior Registrations 2599792
Description of Mark Color is not claimed as a feature of the mark. The mark consists of the stylized words “HOWSMYDRIVING.COM”.
Type of Mark SERVICE MARK
Live/Dead Indicator LIVE