Recommended Axle Flip Kit for a 3,500 lbs Drop Axle

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Question:

My Haulmark 7x16 cargo trailer has Dexter 3500 4" drop axles. I have done a conversion to make it a mini toy hauler. I would like to increase my ground clearance. I see that you have two options available. The axle flip kit, or purchasing straight axles. My question is which product is better for my application? I also wonder about the performance of the suspension? Seems to me, that the flip kit changes the suspension from its factory position. Thank you,

asked by: Brian B

0

Expert Reply:

Hey Brian. I recommend using the Dexter Trailer Springs Over-Under Conversion Kit item # K71-384-00. We've had quite a few customers over the years make this change their trailers with lots of success. Doing this will give you a lift equal to the axles' diameter and the height of the leaf spring packs.

You're going to change the geometry of your factory suspension either way. Replacing your drop axles with straight ones has all the potential to get expensive depending on how long the hub face measurement is and where your spring seats are located. Plus you'll need new U-bolts.

The Dexter Trailer Springs Over-Under Conversion Kit item # K71-384-00 fits 2-3/8" diameter axles so this kit is exactly what you need for a Dexter 3,500 lbs axle. They're sold individually so you'll need two kits.

If you would like me to check and see if we have a replacement straight axle, I would just need to know your hub face and spring seat measurements.

You can add this information, along with any other questions you have, where it says Reply to Jerred H.

expert reply by: Jerred H

0

K71-384-00
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Axle Measurement
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Brian B.

1/5/2026

Jerred, I really appreciate your insight into my next project, that will improve my little snowbirding home. I am from Milwaukee, and currently in Brownsville, TX checking out the Space X Starship factory. I will be heading west, and the added clearance should get me into some really great boondocking spots. With your recommendation, I will be placing an order today for 2 sets of the axle flip kits for my trailer. Thanks, Brian Bogue

Jerred H.

1/5/2026

@BrianB You're welcome! Glad I could point you in the right direction. The Dexter Trailer Springs Over-Under Conversion Kit item # K71-384-00 will definitely get you that clearance you need to go out farther. That sounds like such a fun trip. My parents took me down to the Houston Space Center when I was a kid and I couldn't believe how massive everything was. Watching a shuttle launch is definitely on my bucket list.

Brian B.

1/5/2026

@JerredH What a great memory! How about an equalizer upgrade that will work on my new set up with the over under kit? Thanks, Brian

Jerred H.

1/7/2026

@BrianB It really is and you're welcome! To recommend an equalizer upgrade kit, I'll need to know the width of your current equalizer from the center to center of the mounting holes. I'll also need to know how wide your shackle straps are from the center of each mounting hole. Swapping out the equalizers will require you to get new suspension bolts. They're only meant to be torqued down upon initial installation. I also recommend replacing your leaf springs while you've got the suspension all taken apart. If you could get me the measurement from the center to center of the mounting bolts with the weight of the trailer off of the suspension on one side, I can find you some replacements. I'll also need to know how many leafs you're wanting in the springs.

Answer 1

If you happened to have enough ground clearance you could go with a straight axle but you would be losing about 4 inches of clearance between the tires. I attached a link to both styles of 3,500 lb axles we carry as well.

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Answer 2

Hey Alex, if you don't mind swapping your drop axle to a straight axle that would be a great way to gain the additional height over using an over under kit. That would be a lot more expensive than a over under kit part #K71-384-00 so keep that in…

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Answer 3

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Answer 4

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Answer 5

Hi Paul, you’re definitely on the right track here, and I can help you narrow this down with confidence. With your tandem 3,500 lb Dexter axles and 33 inch spacing, both the Dexter EZ Flex part #K71-652-00 and the Lippert Road Armor part #LC53CK are…

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Answer 6

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Answer 7

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Answer 8

You can use leaf springs that are rated higher than the axle without any issues as long as they measure the correct measurement for your trailer. For example the 6-leaf double eye spring for 7,000 lb axles part #e64SR measures 24-7/8" eye to…

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Answer 9

It sounds like you are speaking of the wires for the brake magnets. If this is correct, you will need to connect one of the wires to the brake controller output wire on your trailer connector and the other wire will need to be grounded to a clean…

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Answer 10

The #84 spindle is just a common way to identify the spindle dimensions typically used for 3,500 lb axles. So instead of listing out the parts, people can just say they have #84 spindles and it's easier to know what fits it. The CE Smith Trailer…

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Answer 11

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Answer 12

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Recommended Axle Flip Kit for a 3,500 lbs Drop Axle

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