Frequently Asked Questions About Peterbilt Polishing

What grades of aluminum are Peterbilt bumpers made from, and how does this affect polishing results?

Most Peterbilt bumpers from 2000 onwards are made from 3003 or 5052 aluminum alloy. The 3003 alloy polishes to a bright mirror finish more easily but may require more frequent maintenance. The 5052 alloy is harder and more durable but takes more effort to achieve that initial mirror shine. Pre-2000 models often use different alloys that may oxidize differently. We recommend using progressively finer compounds starting with 400-grit for heavily oxidized bumpers, moving through 800-grit, then finishing with a premium aluminum polish for best results.

Which Peterbilt models and years require special polishing techniques or products?

Peterbilt 379 (1987-2007) and 389 (2008-present) bumpers have different contours that affect polishing technique. The 379 has sharper edges that require careful hand detailing, while the 389's rounded design allows for easier machine polishing. Models 567 and 579 (2013-present) often feature composite plastic end caps that must be masked off during polishing. For 359 models (pre-1987), the chrome-plated bumpers require chrome polish instead of aluminum compounds. Always verify your specific model year as Peterbilt made mid-year changes that can affect material composition.

What tools and equipment do I need for professional-quality results at home?

For best results, you'll need a variable-speed rotary polisher (1,500-2,500 RPM range), wool compounding pads, foam finishing pads, and microfiber towels. Essential compounds include a cutting compound for oxidation removal, a polishing compound for shine, and a finishing sealant. Budget approximately 4-6 hours for a full bumper restoration. Many customers find success with our complete polishing kits that include all necessary compounds and pads specifically selected for Peterbilt aluminum.

How do I maintain the mirror finish after polishing, and how often should I repolish?

Apply a quality aluminum sealant immediately after polishing to protect against oxidation. In moderate climates, expect to do touch-up polishing every 2-3 months and full repolishing annually. For trucks exposed to road salt or coastal conditions, increase touch-ups to monthly. Between polishings, wash with pH-neutral soap and dry immediately to prevent water spots. Avoid automatic truck washes with harsh chemicals. Many drivers keep a small bottle of quick-detail spray and microfiber cloth in their cab for spot maintenance.

What are the most common mistakes that damage bumpers during polishing?

The biggest mistake is using too much pressure or speed, which creates heat swirls and can warp the aluminum. Never exceed 2,500 RPM or let the surface get too hot to touch. Using the wrong compounds is another issue - never use chrome polish on raw aluminum or steel wool on any Peterbilt bumper. Failing to mask off plastic parts, lights, and painted surfaces leads to damage from compound splatter. Finally, polishing in direct sunlight causes compounds to dry too quickly, leaving difficult-to-remove residue. Always work in shade or indoors when possible.