Replacing Old Slipper Springs and U-Bolts
Question:
How do I know when it is time to replace the leaf springs on my trailer? They are rusty, but I dont know if that matters aside from looks. The U bolt looks like it might need replacement even if the springs dont. Im not concerned if this stuff isnt shiney, just as long as it is safe and not likely to leave me broken down beside the road. Ive attached photos and would like recommendations on what I need. Trailer is used to haul a ComPac 16, loaded to go it weighs about 1900 pounds and I estimate the trailer at 300 pounds.
asked by: N P
Helpful Expert Reply:
Though the leaf springs are rusty, they do not seem to look pitted, so they should still be fine. It wouldn't hurt to clean them off with WD-40 or a rust remover to make sure they don't get worse. If you did want to replace them though, you could go with something like the Universal Group # SP-040275. As I couldn't tell 100% how wide the leaf spring is, this is a 1 3/4 wide one. It is also much longer with the overall length of 30 inches, so the rear hanger would most likely need to be relocated a little further back.
The U-Bolts, however, do look like they need to be replaced. I also need to mention the U-Bolt are not installed properly. The CE Smith U-Bolt Kit # CE23103 is for a 2 inch square axle, which is what the pictures look to show. The U-Bolts should be on either side of the leaf spring with a plate going over the leaf spring. When the nuts are tightened on the U-Bolts, it would then clamp the plate down on the leaf spring. I included a review video that should help with how these should be installed as well.

Products Referenced in This Question
CE Smith U-Bolt Kit for Mounting 2" Square Trailer Axles - 4-1/2" Long U-Bolts - Zinc
- Trailer Suspension Parts
- U-Bolt Kits
- Boat Trailer
- Snowmobile Trailer
- 3500 lbs
- Square Axle - 2 Inch
- 1/2 Inch Diameter
- 4-1/2 Inch Long
- CE Smith
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