Tires and Axles

The facts on axle swap vs "flipping"

Underslung and Overslung refer to the position of the leaf spring pack in relation to the axle.
Underslung - Spring Under Axle
Overslung - Spring Over Axle

Swapping a 4" drop axle for a straight axle is the best way to gain true ground clearance. What many refer to as "flipping" an axle is actually changing your axles from an Underslung configuration to an Overslung. To be done correctly requires precise setup and welding new perches on the axle tube.

When moving the axle to the under side of the leaf springs (Overslung) you do not gain any additional clearance on the axle itself, only on the body and frame.
We do not offer this service, however we do perform axle swaps quite often on our builds.

Swapping out a 4" drop axle for a straight axle will give you an additional 4" of axle clearance as well as additional clearance on the trailer body and frame.

Most trailer axles are designed with a positive camber or bend in the tube that will deflect when a load is applied. This is designed to bring the trailer wheel camber toward a 0 value that is the best setting for most trailer applications. This will allow the tires to wear evenly and allow the longest tread life.
If the axle spindle is bent or you actually flipped the axle, it would cause a negative camber which will cause excess tread wear on the inside of that tire.

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Tire Size Changes

If you are thinking about changing the size of tires on your rig, this link may be very helpful in making your decision.



Online Wheel Offset Calculator

Swapping Axles

If you are thinking about swapping the axles you need 3 measurements, and the actual axle rating.

Measurements:

How to measure lug bolt pattern:


How to measure your axle:


The axle rating should be on the trailer GVWR Placard and also on the axle itself.

Placard:


Axle Tag:


A good place to order axles for your CTC:
TheTrailerPartsOutlet