Frequently Asked Questions About Mack R Truck Mud Flaps
Will these mud flaps fit my specific Mack R model year, and what about RD, RB, or DM models?
Our Mack R truck mud flaps are designed to fit Mack R models from 1987-2004, including R600, R688, and R690 series. They're also compatible with RD models (1987-2004), RB models (1987-2004), and most DM models within the same year range. The mounting brackets are universal for these models, using the existing frame holes. However, dump truck applications may require different bracket positioning due to body variations. We recommend measuring your current setup or contacting us with your VIN for exact fitment confirmation.
What's the difference between rubber and polymer mud flaps, and which holds up better?
Rubber mud flaps are traditional heavy-duty options that resist tearing and handle extreme temperatures well, typically lasting 2-3 years with regular highway use. They're heavier (about 8-10 lbs per flap) and may sag over time. Polymer mud flaps are lighter (4-6 lbs), more flexible, and resist chemicals and UV damage better, often lasting 3-5 years. They won't crack in cold weather like some rubber options. For dump trucks or severe service, rubber is often preferred for its weight and durability. For highway and regional hauling, polymer offers better fuel economy and appearance retention.
Do I need special brackets or hardware, or can I use my existing mounting setup?
Most Mack R trucks have standard mud flap hanger brackets that our universal mud flaps will bolt directly onto using the existing 3/8" or 1/2" bolt holes. If you're replacing OEM flaps, you can typically reuse your current brackets and hardware. However, if your brackets are bent, rusted, or missing, we offer complete bracket kits specifically designed for Mack R series frames. The standard bracket spacing is 24" wide, but custom drilling may be needed for some specialty bodies or if you want to adjust the flap position.
What sizes are available, and how do I know which size I need?
Standard sizes for Mack R trucks are 24" x 30" for single axle applications and 24" x 36" for tandem setups. Measure from your bracket mounting point to approximately 6-8 inches from the ground when the truck is loaded. The flap should hang straight without dragging but be long enough to provide adequate spray protection. Wide-base single tires typically need 30" wide flaps instead of the standard 24". For lowboy or heavy haul applications, you might need adjustable anti-sail brackets to prevent flap movement.
Are weighted or anti-sail mud flaps worth the extra cost for my application?
Weighted mud flaps have a steel or lead insert at the bottom that adds 2-4 pounds, keeping them hanging straight and reducing sail effect at highway speeds. They're especially valuable for flatbed operators or anyone running empty frequently. Anti-sail brackets are spring-loaded or rigid supports that prevent the flap from flipping up, crucial for dump trucks to prevent damage when backing under hoppers. Standard flaps work fine for most applications, but if you've experienced torn flaps, damaged trailers, or DOT violations from flapping mud flaps, the upgrade typically pays for itself within a year.
