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Reese
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Reese has designed towing equipment since 1952 and remains a benchmark for heavy-duty towing. The line covers fifth wheel hitches such as the modular M5, gooseneck couplers including the Goose Box, air-ride and short-bed pin boxes, weight distribution systems with active sway control, and the accessories that connect them, all built to exceed published industry standards.
Reese has been pioneering towing performance since 1952, when Margaret Reese asked her husband TJ to stop travel trailers rocking every time somebody walked through them. His answer, the first pair of stabilising jacks, was simple and effective enough to change the RV industry. From that starting point Reese grew into a designer and manufacturer of complete towing systems, and today it anchors the heavy-duty end of the Horizon Global towing portfolio.
Fifth wheel towing is where the brand's engineering is most visible. The M5 fifth wheel hitch uses a modular design that breaks into manageable sections for assembly, with a wider stance, tighter tolerances and a shock absorption system aimed at the jolts that travel up through a truck bed. For owners who would rather tow from a gooseneck coupler and keep the bed clear, the Goose Box 20K replaces the trailer's king pin with a gooseneck connection carrying its own air-ride cushioning.
Pin boxes are a Reese speciality. The 5th Airborne uses air-ride technology to dampen road shock and reduce the chucking motion that makes fifth wheel towing tiring, while the Sidewinder was designed for short-bed pickups, pivoting the connection point so the trailer can turn sharply without the front cap meeting the cab.
For conventional towing, Reese weight distribution systems restore load to the tow vehicle's front axle and control sway. The Pro Round Bar distributes weight evenly while damping sway, and the Pro Dual Cam II uses active cam-based sway control that works harder the stronger the sway force becomes. Complete kits pair bars, head and shank to a rated tongue weight, and dedicated sway control kits can be added to existing setups. The products suit RV owners, horse and livestock haulers and anyone towing near the upper end of a vehicle's rating.
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The M5 MY20 GM Leg is a support leg assembly for a fifth-wheel hitch that attaches to the center section of an M5 fifth-wheel hitch system. It comes pre-assembled, adjusted, and ready to install. The legs support the hitch and trailer when connected to a GM truck bed, and they lock into place using handles and lynch pins.
No. The M5 MY20 GM Leg is designed specifically for installation with the M5 Head and M5 Center Section (sold separately). You must use these components together as a system.
Your truck bed must have pucks (mounting points) to accept the leg handles. The manual does not specify which GM truck models include factory pucks or whether they must be added separately. You should verify your truck has bed pucks before purchasing. The legs position over these pucks and lock in place with handles and lynch pins.
Yes. You must ensure a minimum of 6 inches of clearance between the truck bed rail and the bottom of the trailer. The manual states you should determine which center section mounting holes to use to achieve this clearance. For detailed guidance on matching the hitch, truck, and trailer, refer to the guidelines in the M5 Head and Center Section instruction sheet.
Yes. The unit has 4 inches of vertical adjustment. Legs must be attached at the same height on both sides of the unit. You determine which center section mounting holes to use based on your truck and trailer combination to maintain the required 6-inch minimum clearance.
The kit includes: 1 M5 GM Leg assembly; 4 M16 x 2 x 40mm CL10.9 hex head bolts; 4 5/8-inch conical washers; 4 T-pin locking handles; 4 lynch pin handle locks; 4 castle nuts (M5 Ford); 4 T-pins (Ford M5); and 4 T-bushings (Ford M5).
You will need: M24 wrenches, pliers, and a torque wrench. The torque wrench is essential because the M16 hex head bolts must be tightened to a specific torque specification of 220 ft-lb.
The M5 MY20 GM Leg comes pre-assembled, adjusted, and ready to install. You do not need to assemble the leg itself; you only need to attach it to the center section and position it in your truck bed.
Using the 4 M16 x 2 x 40mm hex head bolts, attach the legs to the center section structure by threading the bolts from the inside of the center section into the threaded portion of the legs. Finger-tighten the bolts initially until final adjustments are made. Do not fully tighten them yet.
During assembly of the M5 MY20 GM Leg to the center section, make sure that the collars on the leg are completely seated in the corresponding holes in the center section. This ensures proper alignment and support.
Remove the 2 lynch pins and position the legs over the pucks in the truck bed with the handles in the OPEN position. Once the unit is placed in the pucks, rotate the handles back to the CLOSED position and insert the lynch pins back into the leg to prevent the handles from opening during operation.
Due to variations in truck underbeds, it is normal for some handles to be loose and others to be too tight to lock. If a handle appears too loose and rattles or cannot be closed fully, remove the lynch pin and adjust the castle nut by hand to a position where the handle does not rattle or is able to close. Only finger-tighten the castle nut. Once adjustment is satisfactory, re-insert the lynch pin and close it properly.
Each M16 hex head bolt that connects the legs to the center section must be tightened to 220 ft-lb of torque. Tighten the bolts only after the leg T-pin handles are locked and the T-pins are securely held in the underbed structure.
Finger-tighten the M16 bolts initially when attaching the legs to the center section. After positioning the legs in the truck bed pucks, closing the handles, and inserting the lynch pins, then tighten each M16 hex head bolt to 220 ft-lb of torque.
After tightening the M16 bolts to 220 ft-lb of torque, verify that the hitch is tight to the truck bed by lifting each side of the hitch. There should be no movement or play. Then assemble the head to the center section per the instructions included with the M5 Center Section and Head.
Failure to follow installation and hitch-up instructions may cause property loss, serious injury, or death. Additionally, do not exceed the towing vehicle manufacturer's recommended towing capacity. Always ensure all lynch pins, foot brackets, and castle nuts are undamaged and securely locked before any trip.
Before any trip, verify that all lynch pins, foot brackets, and castle nuts are undamaged and securely locked, with little to no vertical play. The lynch pin should be in the proper closed position relative to the foot. If any component is loose or damaged, do not operate the hitch until it is repaired.
Every 1,000 miles, check the M16 hex bolts that connect the center section to the legs to ensure they are still torqued to 220 ft-lb of torque. Retighten them if necessary to maintain proper installation.
For general maintenance of the entire M5 fifth-wheel hitch assembly (head and center section), refer to the M5 Head and Center Section instruction sheet. The M5 MY20 GM Leg manual covers only the leg assembly maintenance.
The M5 MY20 GM Leg is designed for GM trucks with bed pucks. You must have truck bed pucks to mount the leg handles. The manual does not specify which GM models are compatible; contact the manufacturer or your installer to confirm fitment for your specific truck.
You need M24 wrenches, pliers, and a torque wrench. The torque wrench is essential to tighten the M16 bolts to 220 ft-lb.
No drilling is required. The legs attach to the center section using existing threaded holes and bolt directly into truck bed pucks.
Tighten each M16 hex head bolt to 220 ft-lb of torque. Check and retighten every 1,000 miles.
Only if a handle is too loose or too tight. Finger-tighten the castle nut by hand to adjust handle tension. Most handles will not require adjustment.
Yes, maintain a minimum of 6 inches of clearance between the truck bed rail and the bottom of the trailer. Use the appropriate center section mounting holes to achieve this.
Lift each side of the hitch after tightening the bolts to 220 ft-lb. There should be no movement. All lynch pins must be closed and secured, and all fasteners must be tight.
Before every trip, verify all lynch pins, foot brackets, and castle nuts are secure. Every 1,000 miles, retorque the M16 bolts to 220 ft-lb.
The M16 bolts may not be tightened to the correct torque specification of 220 ft-lb. Verify each bolt is torqued to exactly 220 ft-lb using a torque wrench. Also check that all lynch pins are fully closed and secured, and that the leg collars are completely seated in the center section holes. If movement persists after retorquing, the bolts, collars, or center section may be damaged.
This is normal due to variations in truck underbeds. Remove the lynch pin from the affected handle and adjust the castle nut by hand (finger-tighten only) to a position where the handle does not rattle and closes fully. Reinsert the lynch pin and close it properly. If the handle still rattles after adjustment, the castle nut, T-pin, or handle may be damaged.
The bolts may loosen due to vibration during towing if they were not tightened to the correct specification or if the leg collars are not completely seated in the center section holes. Verify the collars are fully seated, then retorque each bolt to exactly 220 ft-lb. Check the bolts every 1,000 miles. If bolts continue to loosen, the bolt holes or threads may be damaged.
Sam
Ordered online. Shipment arrived on time and with all the correct parts. Great customer service and friendly staff. Also, pricing was great!
May 22, 2023
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