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How To's

Installation of Full Tandem Fenders With Outside Fender Mounts

Review HOW TO USE E-Z MOUNT BRACKET SYSTEM and pre-assemble your brackets.

Determine the best location for your fenders to be mounted and temporarily block or support the fender into desired position. We suggest using a 1” x 4” x 12” strip of wood across the top of the tires. Using shims where necessary, center the fender on the blocks, making sure the fender is level with the frame.

(NOTE: It is important to keep the fender an equal distance from the frame. Periodically check the distance, front and rear, by measuring from the outside edge of the fender to the frame.)

Using the E-Z Mount Outside Fender Bracket, (single stud or post mount) install the front bracket either into the predetermined hole in frame or the post mount on the suspension. If you are using a single stud mount, tighten the Nyloc nut so the bracket rotates firmly. If you are using the post mount, secure the clamp so the bracket rotates firmly. We suggest that you mount your front and rear brackets within a range of 12” to 16” from the bottom edge of the fender to the center of the bracket arm. It is important that you do not leave too much fender below your bracket, as the air from driving or passing other trucks could potentially cause the bottom of the fender to flex and the radius of the fender to bend or crack.

With the bracket mounted firmly to the frame, hold the fender up to the bracket and insert the first and fourth grommets in place between the fender and bracket. Mark the fender at the outside end of the bracket, and along the top of first and fourth grommets.

Remove the fender from the blocks and set on the floor. Hold the 1 1/2” x 19 3/4” backing plate across fender. Line up the top of the backing plate with the marks you made along the first and fourth grommets and the outside end of the backing plate with the marks you made at the outside end of the bracket.

(NOTE: It is important that the marks are equal distance from the bottom edge of the fender, this will ensure that the fender is mounted straight.)


Using your backing plate as a template drill the four holes in the fender. (NOTE: Remember to only drill the four holes that line up with the bolt holes in your bracket. The other holes are for the tabs on the tab lock washers, to keep the 3/8” x 1 3/4” bolts from loosening when the job is complete.) It is helpful to insert each 3/8” bolt into each hole as they are being drilled. This will ensure the backing plate remains lined up properly.

After you have drilled the four holes in your fender we suggest that you enlarge them to 13/32”. This will allow for adjustment when bolting the fender to the bracket. Place the fender back onto the blocks and temporarily bolt the fender to the bracket using the first and fourth holes. Be sure to put grommets between fender and bracket. Proceed to the rear of the fender and repeat the same process.

After you have drilled the four holes in the fender for the rear bracket, place the fender back onto the blocks and bolt the fender to the brackets. Be sure to put grommets between the fender and the brackets using the backing plate and tab lock washers under the fender. Torque the 3/8” x 1 3/4” bolts to 10 ft/lbs. front and rear. (NOTE: Remember to bend the tabs on the tab lock washers down against the hex head of the 3/8” bolts holding the backing plate.)

When you have completed mounting the front and rear brackets, place the E-Z Mount Center Support Bracket into the predetermined frame hole. (NOTE: If possible, utilize the fifth wheel rail hole.) Tighten the 5/8” Nyloc nut into the frame so the bracket rotates firmly (NOTE: If you are using a 8” or 10” bracket do not mount bracket at an angle greater than 45 degrees. If you are mounting either bracket at an angle greater than 45 degrees, YOU MUST USE the next size shorter bracket.) Rotate the bracket upwards to meet the bottom of fender and tighten the 5/8” Nyloc nut into the frame. The fender should rest evenly and firmly on the bracket plate. If the bracket has pushed the fender upwards, or pulled away from the bottom of the fender, loosen the 5/8” Nyloc nut and re-adjust the bracket.

(THIS IS VERY IMPORTANT.) Adjust bracket plate in or out so all the fender bolts are in line and drill holes into the fender. (The fender does not need to be removed.) Install stainless button head bolts through fender and bracket plate and tighten all Nyloc nuts on center support bracket.

Torque 5/8” Nyloc nut to 150 ft/lbs.

Replace the air in the suspension.

Mounting is complete.