Upgrading Axle Capacity on 5th Wheel With 3,500 lb Axles

Updated 09/30/2025 | Published 09/03/2025

Products Featured in This Question

Timbren Axle-Less Trailer Suspension w Electric Brakes - Standard Duty - No Drop - 5 on 4-1/2 - 3.5K

(26)

$1478.57

Dexter Trailer Axle Beam with E-Z Lube Spindles - 86-1/2" Long - 5,200 lbs

(802)

$299.07

etrailer Electric Trailer Brakes - Self-Adjusting - 12" - Left/Right Hand - 5.2K to 7K

(3165)

$193.37

Easy Grease Trailer Hub and Drum Assembly for 5.2K & 6K Axles - 12" - 6 on 5-1/2 - Pre-Greased

(1819)

$186.24

U-Bolt Kit for Mounting 5,200-lb to 7,000-lb, Round Trailer Axles - 7" Long U-Bolts

(2120)

$59.74

4-Leaf Double-Eye Spring for 5,200-lb Trailer Axles - 25-1/4" Long

(307)

$142.67

Spring Seat for Typical 5,200-lb to 7,200-lb, Round Trailer Axles with 3" Diameter

(648)

$11.95

Question:

Hello, I have a 5th wheel RV dual axle with 2 -lippert lc135-86.5-68.5-os. I would like to upgrade to a higher load capacity as this is constantly maxed out even when the trailer is dry. Can you recommend an 5200 lb axle? It has the following spring pack - 6 Leaf Double Eye Spring - 1-3/4 Wide - 3.5k Cap. - 25-1/4 Eye to Eye. Thank you

asked by: David

Expert Reply:

Hi David; a trailer wouldn't be designed where it exceeds the axle capacity without even being loaded. The axles will always be able to handle the GVWR of the trailer. You might not be factoring in the pin weight, which is weight that won't be sitting on the axles. The same is true for tongue weight on bumper pull trailers.

You can still upgrade the axles if you want, but it won't actually increase the capacity of the trailer. Even if you swap out the axles, leaf springs, and hubs you will be limited by the trailer frame. The Dexter Trailer Axle Beam with E-Z Lube Spindles - 86-1/2" Long - 5,200 lbs # 8327816 matches your current axle length so it can be used as a replacement. The spring seat measurement is different so you will have to cut off the spring seats and weld on # TRSS300 to match your 68-1/2" measurement.

With a different axle you will need new hubs # AKHD-655-6-EZ-K and brakes # AKEBRK-7-SA. You will also need a U-bolt kit # APUBR-8 and if you want to upgrade the leaf springs # DX45CR. I'm guessing you have a 5 on 4-1/2 bolt pattern now so you will also need new wheels to match the 6 on 5-1/2. I attached a link below to all of our wheels and tires with a 6 on 5-1/2 bolt pattern for your reference.

expert reply by: Robin H

Dexter 5,200 lb Axle
(click to enlarge)

Robin H.

9/29/2025

Hi David, did you decide to upgrade your axles with the Dexter Trailer Axle Beam and the other components I mentioned? I’d love to hear how it worked out for you, as it could help others considering a similar upgrade.

David

9/29/2025

@RobinH Thanks Robin, I am leaning towards upgrading the wheels but leaving the axle as is. Appreciate your responses and advice!! Dave

Robin H.

9/30/2025

@David as in moving to a larger wheel/tire size with a higher rating? You can do this but you need to make sure you have enough clearance for the larger tires.