Upgrading Leaf Springs On Trailer For 3000 lbs Capacity On 3500 lbs Axles

Updated 02/17/2020 | Published 12/10/2016

Question:

I have 3500 lb axels on my car hauler Iam replacing the worn out springs and have looked into and found out I can upgrade to a 2500lb spring SP-218275 and be just fine my question is can I further the upgrade with a small jump to 3000lb SP-111275 and be okay in doing that the loads I carry are pretty sporty 9 to 10,000 lbs. I did all that on 1750 springs hence the worn out springs so would I be ok to upgrade to the 3000 lb? My concern if really any would be the bearings.

asked by: Howard A

Expert Reply:

You can absolutely upgrade your 4-Leaf Double-Eye Spring for 5,000-lb Trailer Axles - 25-1/4" Long, # SP-218275, to the 5-Leaf Double-Eye Spring for 6,000-lb Trailer Axles - 25-1/4" Long, # e34SR. This upgrade will give you the 3000 lb capacity you mentioned, but it will not give you the ability to carry larger loads. Your load capacity is rated by your axles themselves, so although stronger springs will make things less squatty, it will basically just give you a firmer ride on your trailer. Your axles, bearings, hubs, etc. would all have to be upgraded if you were to carry more weight than your axles are rated for.

I'm assuming you already have a triple axle system if you are carrying 10,000 lbs on 3,500 lb axles. If you have double axles, you are already overloading your 7,000 lb capacity trailer and things will continue to wear out or break.

expert reply by: Jason S

Summer D.

2/15/2020

To go from a 4 to 5 leaf spring, will the same u bolts fit? Its a 2 3/8 axle and I cant find the unbolt in a 2 3/8 the length its suggesting.

Jason S.

2/17/2020

You shouldn't need to change your axle u-bolts for a 4 to 5 leaf spring. If you prefer to use new hardware, then I recommend the kit # APUBR-1 which is for the 2-3/8 inch diameter of a 3,500 lb axle.

Helpful Links

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