with reference to fig1 - 4 , numeral 10 refers to a tow behind steerable caddy . the tow behind steerable caddy trailer 10 is designed to follow behind a tractor , an implement pulled by a tractor , or other vehicle . the trailer 10 is designed to follow in the tracks of the towing vehicle to navigate tight turning radiuses . the tow behind steerable caddy trailer 10 thus may negotiate tight turning radiuses in a field with very few end rows or with equipment that has a very narrow operating width . the steerable caddy trailer 10 has a main frame assembly 12 illustrated as a metal square tube . the main frame assembly 12 has opposite ends 14 , a top side 16 , a bottom side 18 , a front side 20 , and a back side 22 . angled end caps 26 are attached at each end 14 of the main frame assembly 12 . it has been contemplated that the end caps 26 could also be a vertical end cap rather than an angled end cap 26 . a vertical end cap may be used in conjunction with a track or in applications requiring additional structural strength to support heavy loads . a spindle assembly 28 is pivotally attached at each end 14 of the main frame assembly 12 . the spindle assembly 28 has a base plate 30 and a top plate 34 connected by an angled extension 36 which ends in a vertical surface with a spindle 40 for a wheel 44 . the base plate 30 and top plate 34 are attached to the angled end cap 26 by a pivot pin 42 . the spindle assembly has a vertical support 38 which strengthens the connection of the base plate 30 and the top plate 34 to strengthen the spindle assembly 28 . a forward base member 32 is provided to extend from the base plate 30 and has a hole for connecting a first end of a tie rod 70 . swinging arms 46 extend from the main frame assembly 12 . each swinging arm member 46 has a rear end 48 that pivotally attaches to the main frame assembly 12 . the rear end 48 has a top support 50 and a bottom support 52 , which extends above and below the main frame assembly 12 to pivotally attach to a cylinder 54 at the back side 22 of the main frame assembly 12 by a pivot pin 61 . the bottom support 52 also has a hole for receiving a front end of tie rod 70 . a front end 58 of the swinging arm members 46 has an adapter 60 for attaching to a rigid cross member , such as the exemplary rigid cross member shown in fig1 in dashed lines . the rigid cross member could be a piece of square tubing ( as shown ). the rigid cross member could also be a bumper , a vehicle , a tractor or other farm implement . it is preferred that the swinging arm members 46 be pivotally mounted to a rigid cross member . for example , attaching a hitch to the adapter 60 and a ball to both ends of the rigid cross member ( as shown in fig1 in dashed lines ) allows the swinging arm members 46 to pivot about the balls . similarly , swinging arm members 46 could also be pivotally attached to a bumper or another rigid cross member as part of a farm implement . in fig1 , the swinging arm members 46 are shown parallel to each other and the tires 44 are shown perpendicular to the main frame assembly 12 . however , the swinging arm members 46 need not be parallel to each other for the trailer 10 to steer . adjusting the swinging arm members 46 affects the turning radius of the steerable caddy trailer 10 . regardless of the configuration , whether the swinging arm members 46 are parallel or moved inward closer to each other , the tie rods 70 can be adjusted to keep the tires perpendicular to the main frame assembly 12 . a platform support 62 is provided that has side supports 64 and a front support 66 connecting the two side supports 64 and sub - platform supports 68 . the platform support 62 balances the weight of a platform , tank , hopper or other evenly towards the front and back of the main frame assembly 12 . in operation , the caddy is pulled behind the implement and / or vehicle by pivotally connecting the swinging arm members 46 to a rigid cross member . should the towing vehicle or farm implement turn left this will simultaneously cause the left swinging arm 72 to shift rearward toward the main frame assembly 12 and the right swinging arm 74 to shift forward away from the main frame assembly 12 . shifting the left swinging arm 72 rearward towards the main frame assembly causes the tie - rod linkage 70 to move the spindle assembly such that the left wheel 76 steers right . similarly , shifting the right swinging arm 74 forward away from the main frame assembly causes the tie - rod linkage 70 to move the spindle assembly such that the right wheel 78 steers right , also . thus , when the towing vehicle turns left the wheels 44 on the steerable caddy 10 turn right so as to track the towing vehicle . should the towing vehicle or farm implement turn right this will simultaneously cause the left swinging arm 72 to shift forward away from the main frame assembly 12 and the right swinging arm 74 to shift rearward toward the main frame assembly 12 . shifting the left swinging arm 72 forward away from the main frame assembly causes the tie - rod linkage 70 to move the spindle assembly such that the left wheel 76 steers left . similarly , shifting the right swinging arm 74 rearward toward the main frame assembly causes the tie - rod linkage 70 to move the spindle assembly such that the right wheel 78 steers left , also . thus , when the towing vehicle turns left the wheels 44 on the steerable caddy 10 turn right so as to track the towing vehicle . in either instance after the towing vehicle turns left or right and returns to driving a straight course , the wheels 44 return to a position perpendicular to the main frame assembly 12 . in this fashion , the steerable caddy trailer is maintained in virtually the same turning radius as the vehicle and / or implement . the invention has been shown and described above with the preferred embodiments , and it is understood that many modifications , substitutions , and additions may be made which are within the intended spirit and scope of the invention . from the foregoing , it can be seen that the present invention accomplishes at least all of its stated objectives .