Current PNR members who have contributed Technical Articles to the Bumper Guardian include: Bill Allard, Scott Anderson, Lou Berquest, Tom Brace, John Campbell, Frank Daly, Bill Deibel, Craig Devine, Val Dickison, Ron Doss, Marty Ellison, Colin Gurnsey, Brian Harding, Barrie Hutchinson, Karen Hutchinson, Brad Ipsen, Sig Linke, Ray Loe, Roy Magnuson, Phil McCurdy, Al McEwan, John McGary, Bill Mote, Paul Murray, Sandy Olson, Kim Pierce, Brian Rohrback, Jon Schoenfeld, Ashley Shoemaker, David Smith, and Jim Tait.
Issue number and page number are supplied in the columns to the left. Where trimmed links to the articles are available, the Topic column at the Right is in Bold type. Here are the categories with listing of article location following:
| Community | Oil & Fuels | Restoration |
| Electrical | Paint & Surface | Specs |
| Engine & Transmission | Parts | Tires & Wheels |
| Judging | Radiator & Cooling | Touring |
| Maintenance |
COMMUNITY
| Issue | Page | Author | Topic |
| 2009-2 | 23 | Richard Anderson | Restoring Alice Ramsey’s Maxwell |
| 2011-1 | 24 | Karen Hutchinson | The Art of Racing in the Rain |
| 2013-1 | 22 | Val Dickison | Tech Tips From the Passenger Seat |
| 2018-1 | 8 | Marty Ellison | Go Engineer |
| 2018-2 | 37 | Brian Rohrback | Powering the Future |
| 2019-1 | 27 | Val Dickison |
ELECTRICAL
| 1967-3 | 14 | Oil Belt Region | Reverse Polarity |
| 1969-2 | 13 | Kerry Gaulder | Generators and Voltage Regulation |
| 1995-2 | 3 | Bill Deibel | On the Subject of Batteries |
| 1997-2 | 10 | Ian Matthews | Principles of Electricity |
| 2001-4 | 16 | Anon | Spark Interference for Radios |
| 2002-1 | 17 | Paul Murray | Microtip: Static Electricity |
| 2004-2 | 11 | Bill Deibel | Microtip: Spark Plugs |
| 2005-4 | 17 | Don Reddaway | Generator Cutout Conversion |
| 2006-1 | 13 | Bill Deibel | Generator Cutout – Addition |
| 2006-2 | 19 | Don Reddaway | Replacing Battery Cables |
| 2007-1 | 11 | Bill Deibel | Procuring Old Electronics |
| 2008-3 | 28 | Bill Deibel | Electric Starter |
| 2008-4 | 18 | Bill Deibel | Lincoln Continental Coil |
| 2009-2 | 15 | Rohrback & Arnold | Avoiding Blackouts and Brownouts |
| 2010-2 | 24 | Don Reddaway | Delco 3-Brush Generator |
| 2012-1 | 22 | Bill Deibel | Wire Insulation |
| 2013-4 | 25 | Karen Hutchinson | LED Lights for Classics |
| 2014-2 | 23 | Bill Deibel | Battery Cut-Off Switches |
| 2014-2 | 26 | Bill Deibel | Candles, Gaslights and Flash-Bangs |
| 2014-4 | 22 | Colin Gurnsey | Classic Radios |
| 2015-1 | 18 | Gunnell & Shoemaker | Spring Battery Check Up |
| 2015-4 | 19 | Bill Deibel | Ignition Part Sources |
| 2015-4 | 20 | Bill Allard | Adjusting Points |
| 2015-4 | 21 | Bill Allard | Audible Turn Signals |
| 2017-1 | 20 | Bill Deibel | Warning Lights |
| 2018-3 | 21 | Marty Ellison | Batteries |
| 2018-3 | 23 | Kirk White | Battery Care |
| 2019-1 | 23 | Bill Deibel | More Batteries |
| 2019-2 | 22 | Al McEwan | Stalled Hispano |
| 2019-4 | 13 | Anon | Lucas Headlamps |
ENGINE & TRANSMISSION
| 1968-1 | 17 | Colorado Classicist | Engine Warm-Ups |
| 1968-1 | 15 | Perfect Circle Piston Ring Co. | Cylinder Honing |
| 1976-1 | 7 | Alec Ulmann | Duesenberg Racing Engine |
| 1991-5 | 11 | Brian Firth | Speed is the Substitute for Cubes |
| 2008-4 | 8 | Brad Ipsen | Cadillac V-16 Engine Design |
| 2016-3 | 18 | Brad Ipsen | 1938 Cadillac V-16 |
| 2016-3 | 20 | Brad Ipsen & Ray Loe | Cadillac Evolution |
| 2019-3 | 15 | Bill Allard | Cylinder Head Manufacture |
| 2019-4 | 7 | Terry McGean | Hydramatic |
JUDGING
| 1965-2 | 5 | George Shufelt | Is Elegance Restorable? |
| 1992-4 | 15 | Ron Doss | Cleaning Tech Tips |
| 1993-2 | 9 | Dick Culp | Here Comes the Judge |
| 1998-1 | 11 | Carl Steig | Judges Accreditation Program |
| 2009-4 | 15 | Karen Hutchinson | Judging Experience |
| 2010-1 | 15 | Brian Harding | Judging |
| 2010-3 | 12 | Don Reddaway | Preparing for a Grand Classic |
| 2011-1 | 10 | Brian Harding | Concours Judging Part IV: In the cabin |
| 2012-1 | 18 | Brian Harding | Judging the Exterior |
| 2012-2 | 9 | Brian Harding | Judging Seminar |
MAINTENANCE
| 1965-4 | 16 | Pete Manello | Shop Talk |
| 1965-5 | 14 | Pete Manello | Sticky Hydrolic Lifters |
| 1970-1 | 15 | Perry and Daphne Fowler | Ultrasound Cleaning |
| 1972-1 | 9 | James Dougherty | Trouble Shooting |
| 1972-1 | 8 | Bill Locke | Shocks |
| 1974-1 | 5 | Frank Starr | Maintenance Tips |
| 1983-4 | 6 | Jim Dougherty | Preventing Car Fires |
| 1985-2 | 5 | Arthur Caldwell | Removing Frozen or Broken Bolts |
| 1988-2 | 11 | Packard Service Bulletin | Understanding Hydrolic Lifters |
| 1993-5 | 19 | Roy Magnuson | Tire Tips |
| 1994-2 | 7 | CCCA: The Joy of Touring | Electrical and Wiring |
| 1994-2 | 7 | Ron Doss | The Perfect Battery |
| 2000-2 | 16 | Jack Collins | Damaged Holes for Trim Screws |
| 2001-1 | 20 | Anon | Stuck in Gear |
| 2004-2 | 11 | Bill Deibel | Microtip: Condensers |
| 2004-2 | 15 | Sam Barer | Safety Check for Classics |
| 2004-3 | 15 | Sam Barer | Understanding SU Carburators |
| 2005-2 | 13 | Don Reddaway | Microtip: Minor Car Repairs |
| 2006-1 | 12 | Lou Berquest | Overdrive Installation |
| 2006-2 | 17 | Bill Deibel | Overheated Overdrive |
| 2006-3 | 11 | Don Reddaway | Rebuilding a Stromberg Carburator |
| 2006-4 | 14 | Don Reddaway | Clark Transmission Rebuild |
| 2007-3 | 13 | Bill Mote & Gary Steinman | Electric Fuel Pump Installation |
| 2008-2 | 19 | Bill Deibel | The API Service Category System |
| 2009-2 | 27 | Val Dickison | Windshield Replacement 101 |
| 2010-1 | 18 | Brian Rohrback | Bentley Service Instruction |
| 2010-3 | 22 | Bill Allard | Ring and Pinion Replacement |
| 2010-4 | 20 | Bill Allard | Fixing Oil Leaks |
| 2011-1 | 9 | Bill Deibel | Reproduction gas sending unit |
| 2012-1 | 11 | Don Reddaway | Small tools, carburetor, gaskets |
| 2012-2 | 11 | Don Reddaway | Microtips: Rust and pot metal repair |
| 2012-3 | 11 | Scott Anderson | Microtips: Tool Care and Gel Wax |
| 2012-3 | 15 | Bill Allard | Startix Repair |
| 2013-1 | 11 | Bill Allard | Microtip: Removing Corrosion |
| 2013-3 | 12 | Bill Allard | Grease Cup Re-sealing |
| 2014-1 | 26 | Bill Deibel | Fixing Screws that don’t tighten |
OILS & FUELS
1986-1 | 3 | Chevron Tech Bulletin | Unleaded Gasoline and Classics |
1989-3 | 13 | Louis Durkee | Motor Oil and Lubricant Tips |
1994-3 | 7 | Bill Deibel | A Few Words About Gasoline |
1999-1 | 13 | Bill Deibel | Vapor Lock and Antiknock |
2007-1 | 20 | Gary Russell | What Kind of Oil to Use |
2008-1 | 19 | Bill Deibel | Understanding Motor Oil Distinction |
2008-4 | 7 | Les Huggins | Oil containing Zinc |
2009-3 | 15 | Bill Deibel | Update on Motor Oil |
2012-1 | 10 | Brian Rohrback | Gasoline by the numbers |
2013-1 | 23 | Don Reddaway | New Gas Troubles |
2014-4 | 30 | Frank Frisch via Bill Deibel | SnapUps |
2016-4 | 14 | Brian Rohrback | Industry Part 1: Octane |
2016-4 | 23 | Brian Rohrback | Industry Part 2: Octane Measure |
2017-1 | 15 | Brian Rohrback | Industry Part 3: Refineries |
2017-2 | 10 | Brian Rohrback | Industry Part 4: Fuel Blending |
2017-2 | 11 | Brian Rohrback | Properties of Gasoline |
2017-3 | 16 | Brian Rohrback | Industry Part 5: Alcohol |
2017-4 | 22 | Brian Rohrback | Industry Part 6: Water |
2017-4 | 23 | Brian Rohrback | Oxygenates |
2018-1 | 22 | Brian Rohrback | Industry Part 7: Fuel Adulteration |
2018-1 | 23 | Bill Deibel | Alcohol & Vapor Lock |
2018-3 | 22 | Brian Rohrback | Industry Part 8: Transportation |
2018-4 | 18 | Brian Rohrback | Industry Part 9: Motor oil |
2018-4 | 21 | Brian Rohrback | Gas Station History |
2019-1 | 20 | Brian Rohrback | Industry Part 10: Extraction |
2019-3 | 22 | Brian Rohrback | Industry Part 11: Oil Exploration |
2019-4 | 22 | Brian Rohrback | Industry Part 12: Origin of Oil |
| 2020-3 | 20 | Brian Rohrback | Industry Part 13: Encapsulation |
PAINT & SURFACE
| 1967-1 | 17 | Richard Terhune | Painting Your Classic |
| 1975-2 | 10 | Lauren Matley | Automotive Refinishing |
| 2012-2 | 19 | Colin Gurnsey | Classic Colours |
| 2015-2 | 28 | Kim Pierce | Bondo |
| 2016-1 | 20 | Kim Pierce | Paint a Car Part I |
| 2016-3 | 26 | Kim Pierce | Paint a Car Part II |
| 2017-4 | 21 | Bill Allard | Powdercoating @ Home |
| 2018-2 | 36 | Kim Pierce | Paint Maintenance |
PARTS
| 1965-4 | 13 | George Shufelt | Nuts and Bolts |
| 1969-4 | 17 | Auto Glass | Types of Glass |
| 2012-1 | 24 | Bill Deibel | Bleak Outlook for Aftermarket Parts |
| 2014-4 | 20 | Frank Frisch via Bill Deibel | Brake Shoe Springs |
| 2015-1 | 7 | Bill Deibel | Carburator Repair |
| 2015-2 | 21 | Lucy Allard | Mr. Bijur and his System Patent |
| 2015-2 | 22 | Val Dickison | Bijur Oil Delivery System |
| 2015-3 | 16 | John Campbell | Emergency Fan Belt |
| 2016-1 | 10 | Frank Daly | Auxiliary Fuel Pumps |
| 2019-1 | 22 | Sandy Olson | Olson’s Gaskets |
| 2019-2 | 27 | Anon | Rescue Tape |
| 2019-4 | 26 | Karen Hutchinson | Headlamp Covers |
| 2019-4 | 25 | Colin Gurnsey | Seatbelts |
| 2020-2 | 8 | John and Mary Campbell | Unobtanium Parts |
RADIATOR & COOLING
| 1967-4 | 18 | Ben Morgan | Cooling System Problems |
| 1996-2 | 8 | Tom Sumner | Avoiding Overheating |
| 2001-4 | 17 | Bob Agnew | Coolant |
| 2004-2 | 11 | Bill Deibel | Microtip: Radiator Boiling Points |
| 2008-3 | 16 | Barrie Hutchinson | Radiator Expansion Chamber |
| 2012-3 | 19 | Colin Gurnsey | Cooling the Aussie Way |
| 2013-2 | 8 | Kennedy, Harris, & Malks | Antifreeze |
| 2013-2 | 10 | Bill Deibel | Microtip: Antifreeze |
RESTORATION
| 1964-1 | 8 | Bob Johnson | Restoration Tips |
| 1964-2 | 6 | Doug Spenser | Valve Restoration |
| 1964-3 | 4 | Doug Spenser | Valve Restoration Part 2 |
| 1964-4 | 8 | Bob Johnson | Restoration Tips |
| 1965-1 | 9 | George Shufelt | First Things First |
| 1965-4 | 16 | Al McEwan | Restoration Hint |
| 1965-4 | 15 | N. Illinois Region | Plating Pot Metal |
| 1967-2 | 14 | Roy Bourland | Plating Tech Tip |
| 1967-3 | 13 | Bill Ferris | Removing Carriage Bolts |
| 1967-3 | 9 | L.F. Brehmer | Upholstering Your Classic |
| 1967-4 | 17 | Bill Ferris | Parts, Polish and Plastic Steel |
| 1968-1 | 17 | Oil Belt Region | Materials List for Restoration |
| 1970-2 | 12 | Perry and Daphne Fowler | Welding Pot Metal |
| 1970-2 | 11 | Tim Howley | Electroplating |
| 1972-1 | 9 | Luke Peters | Glass Scratches |
| 1983-3 | 6 | Tom Brace | Sisyphus Revisited |
| 1983-5 | 4 | Ken New | Woodgraining Made Easy |
| 1989-4 | 9 | Pete McManus | Gas Tank Restoration |
| 1993-5 | 19 | Golden Era Motors | Wheel Repair |
| 2001-2 | 17 | Bill Deibel | Reproduction Idler Gear |
| 2006-4 | 24 | Bill Deibel | Restoring a Black-Out Car |
| 2009-1 | 12 | Phil McCurdy | Restoration: The Body Rotator |
| 2019-1 | 18 | Craig Devine | 3D Printing |
| 2019-1 | 19 | Barrie Hutchinson | 3D Printing Example |
| 2019-3 | 24 | Craig Devine | 3D Printing 2 |
| 2019-3a | 18 | John McGary | Oil Pump |
| 2021-3 | 22 | Jim Tait | 3D Printing 3 |
SPECS
| 1965-2 | 9 | Reprint | Features of a Cord |
| 1975-1 | 3 | Sigfried Linke | Supercharged Mercedes |
| 1999-4 | 6 | Gary Johnson | Liquamatic Drive (41-42 Lincoln) |
| 1999-4 | 7 | Gary Johnson | Reo-Royale Self-Shifter Transmission |
| 2002-4 | 14 | Anon | Packard Carburators |
| 2010-2 | 5 | Raymond Loe | Chrysler T&C |
| 2016-3 | 5 | Jon Schoenfeld | 1937 Cadillac Specs |
TIRES & WHEELS
| 2000-2 | 16 | Allan Franz | Microtip: Hissing Tires |
| 2003-2 | 15 | Josh Malks | Radial Tires on Classics |
| 2006-4 | 21 | Anon | Breaking in Tires |
| 2009-3 | 8 | Wohlwend & Hutchinson | Why Cord Wheels Crack |
| 2015-3 | 35 | Colin Gurnsey | Classic Tires |
TOURING
| 2005-2 | 13 | Don Reddaway | Microtip: Tour Repairs |
| 2007-2 | 16 | Chris Wantuck | Trailering 101 |
| 2008-2 | 14 | Raymond Loe | The Doble Steam Car |
| 2008-2 | 17 | Gary Johnson | Complete CARavan List |
| 2011-1 | 23 | Karen Hutchinson | Cost of a Tow |
| 2015-1 | 30 | Colin Gurnsey | Touring Tips – 1 |
| 2015-2 | 30 | Colin Gurnsey | Touring Tips – 2 |
| 2019-2 | 9 | Gary Johnson | CARavan List |
Classic Car Club of America - Pacific Northwest Region 