How to Find Correct Replacement Leaf Springs & Axle

Question:

I have a 4x8foot 1720lbs harbor freight trailer I have added welded supports into the frame and have welded the frame seams together to add strength. However Ive noticed while driving down the road, I had a lug nut crack off of the bolt hub due to the trailer being overweight and the axle bending downwards Im guessing. The current weight of the trailer with its cargo is 2,300 lb. Is there an axle and leaf spring assembly you can recommend for me to use? I currently have a five by four and a half bolt pattern with 13-in tires: 2-Pk Radial Trailer Tire On Rim ST175/80R13 175/80R-13 C 5 Lug White Spoke Wheel. I would prefer to not have to buy new tires if I can avoid it and use the ones that I currently have. I would also prefer to not have to weld on a leaf spring but can do that if absolutely necessary. Can you recommend me a new axle and potentially leaf springs for my setup? I imagine if I just bought an axle, I would also need to upgrade the leaf springs as if I were just to buy an axle, the weakest point on my trailer would then be the stock leaf springs only rated to 1720 lb??

asked by: Chris D

Helpful Expert Reply:

I can help you determine how to find the correct replacement leaf springs as well as axle, but there are measurements that need to be taken which will determine the right ones, which is why I can't outright just give you the correct axle.

Let's start with the axle, and in order to choose the correct replacement for your trailer you will need to know the dimensions of your current axle's hub face to hub face and spring center to spring center; I have added a link below to a video which walks you through how to measure. The other thing you need to know is the weight capacity of the axle you need, and since you mentioned 2,300 lbs, the closest we have to that (because it needs to go over that weight) is a 3,500 lb axle.

For example, the Dexter Trailer Axle with Idler Hubs # 35545I-ST-89 has a 3,500 lb capacity and measures 89 inches from hub face to hub face and 74 inches from spring center to spring center. It also comes with hubs that have a 5 on 4-1/2" bolt pattern so it would work with your wheels.

For the leaf springs what you'll need to do is measure your current leaf springs from center-to-center of the spring eyes, and because leaf springs also flatten a bit over time, you should go with ones that measure a bit shorter than what you currently have. For example, if yours measured 26-7/8", for 3,500 lb leaf springs you would go with the 4-Leaf Double-Eye Spring for 3,500-lb Trailer Axles - 27" Long # e97SR.

I have added a link below to our entire selection of both trailer axles and leaf springs, which you can filter through by size and weight.

expert reply by: Kyle S