Find Attachments for your CATERPILLAR RD4. With shipping, financing options available, MarketBook is your one-stop site for all of your CATERPILLAR RD4 40 HP to 99 HP Tractors needs. Browse and search our easy-to-use site for a wide range of 40 HP to 99 HP Tractors and more from listing members like MacFadden & Sons Inc. and others. Find CATERPILLAR RD4 Tractors you need on MarketBook!