How to Change the Leaf Springs on a Dual-Axle Boat Trailer
- 1). Park the boat in a boat slip while the repairs are made. Do not attempt this repair with the boat on the trailer.
- 2). Loosen the lugs on the rear tires with the lug wrench but do not remove them. Jack up the rear end and place the jack stands under the rear frame.
- 3). Finish removing the lug nuts and set the rear tires aside.
- 4). Loosen the bolts attached to the bottom of the U-bolts on the driver's side axle with an impact wrench. Lower the axle.
- 5). Remove the spring bolts from the shackle forks on each end of the leaf spring and remove the old leaf spring. Use the impact wrench to remove the spring bolts.
- 6). Hold the new leaf spring in place while inserting the spring bolts by hand to get them started. Tighten them with the impact wrench.
- 7). Repeat Steps 4 to 6 to change the leaf spring on the rear passenger side and then replace the rear tires and tighten the lug nuts with the lug wrench.
- 8). Jack up the rear end and of the trailer, remove the jack stands and then lower the trailer completely.
- 9). Repeat Steps 2 through 6 to change the leaf springs on the front driver and passenger sides.
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