Replacement Leaf Springs and Tire for 13ft Rocket International Supreme Boat Trailer
Question:
I’ve got a 30 year old rocket International supreme galvanized 13 1/2 foot boat trailer with a 13 foot skiff and outboard weighing approximately 400 pounds. The current leaf springs are 2 leaf slipper springs 27 inches long and 1+3/4 inches wide with a 5 inch that fit in a space thats 23 1/2 inches from the center of ring end bolt to the center of the bolt that keeps the slipper end from falling down. I would like to replace the springs. Do you have something that would work? Although the axel is two inches by two inches there is a prominence of about 3/4 inch on the bottom where the spring attaches. Also I need two 480 x 8 tires to mount on some aluminum hubs that I have. I’ve heard this can be a little difficult sometimes as the Tires come kind of squished down and once on the rim it can be hard to get a seal. Is that a common problem experienced by your customers?
asked by: Tom S
Expert Reply:
Thank you for all of that information; it definitely makes it easier to identify the appropriate parts, and it looks like you were on the right track. If your boat and trailer weigh less than 1000-lbs total, the UFP Slipper Spring for 1000-lbs Axles # SP-177275 is 24-5/8" long and will fit perfectly in the 23-1/2" center eye to slipper spring bolt hanger that you mentioned. If you think the boat and trailer combined weighs a bit over 1000-lbs, the # SP-178275 are a 1500-lbs spring with the same dimensions that would also work and provide you with the necessary support you need.
For the tires, you can use the Kenda Loadstar K37 # AM10002 which are a 4.80-8 tire with a Load Range B capacity of 590-lbs per tire (1180-lbs total). I really like these Kenda tires because they have a 1-year worry-free guarantee. If within the first 12 months the tire is damaged in any way, it will be replaced at no charge, so it's going to give you that extra little peace of mind.
In regards to how the tires are shipped, they do sometimes get smashed during transit but it does not damage them and they can still be mounted on the wheels. With that said, you could go with a wheel/tire combo like the Kenda 4.80/4.00-8 Bias Trailer Tire with 8" Galvanized Wheel - 5 on 4-1/2 - Load Range C # AM30070 to avoid any potential issues at not much more of a cost and it would save you the trouble of having to have the tires mounted.
I've linked a short review video on the tires for you to have a look at, as well.

Products Referenced in This Question
Kenda Loadstar K371 Bias Trailer Tire - 4.80/4.00-8 - Load Range B
- Trailer Tires and Wheels
- Tire Only
- Bias Ply Tire
- Load Range B
- 4.80/4.00-8
- 8 Inch
- Kenda
more information >
Kenda 4.80/4.00-8 Bias Trailer Tire with 8" Galvanized Wheel - 5 on 4-1/2 - Load Range C
- Trailer Tires and Wheels
- Tire with Wheel
- Bias Ply Tire
- Load Range C
- 4.80/4.00-8
- 8 Inch
- 5 on 4-1/2 Inch
- Steel Wheels - Galvanized
- Kenda
more information >
Product Page this Question was Asked From
2-Leaf Slipper Spring w/ Radius End for 1,000-lb Trailer Axles - 24-5/8" Long
- Trailer Leaf Springs
- Slipper Springs
- Radius End
- 1000 lbs
- 1-3/4 Inch Wide
- 2 Leaf
- 24-5/8 Inch Long
- Universal Group
more information >
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