Northern Tool 4ft Overland Trailer Build

rnArmy

Adventurer
Yes, I agree it is probably better to be a little over-sprung (to a point) than under-sprung if you have to choose. However, I do know a little bit about taking a little HF-type trailer frame, expanding it out, adding a cooler tray up front, having a tub built, changing axles, and adding weight. And swapping out the suspension (and experiencing the before-and-after results). These HF-type frames make an awesome basis for a little overlanding adventure trailer.

Mini Harbor Freight (type) Trailer Ultimate Build-Up Thread - JeepForum.com

Having taken my little trailer literally thousands (and thousands) of miles (on and off pavement) on both the factory slipper springs and longer double-eyed springs, the differences are amazing. I learned quickly after my first trip with the trailer (with factory slipper springs) up to Alaska and watching it go airborne too many times. With the longer eye-to-eye springs, no more (or greatly reduced) bouncing with the tires leaving the road. No more gear getting beat-up inside the trailer's tub. You can get eye-to-eye springs in a multitude of lengths and spring ratings (with the same 1.75" width as the factory slipper springs). The factory slipper springs may support the weight, but there's no movement in the suspension when the going gets rough.

Double Eye Trailer Leaf Springs (stengelbros.net)

Single-Axle Trailer Hanger Kit for Double-Eye Springs - 3-1/4" Front, 9/10" Rear Redline Trailer Leaf Spring Suspension APS5

H-110 HANGER TYPE = 2-EYE , A = NB-1 , B = , WIDTH = 1.75 (stengelbros.net)

These are my current springs:

US-1094 Type EE (Eye/Eye) Utility and Boat Trailer Spring 1.75 inch Width; 27.75 inch Overall Length; 975 lb rating per spring (stengelbros.net)

It is a very inexpensive project that yields great results. Plus it would give him the opportunity to move his axle a little forward if he so desired.



Overland Adventure.1.jpg

Overland Adventure.2.jpg
 
Last edited:

OverlandNA

Well-known member
Thank you for your service.
As I recall you changed out the slipper springs because you wanted a smoother ride. Many miles later that set or the next broke and you changed them out again and that set broke. Now you have 1950lbs worth of springs on a trailer with a 1200lb GVWR?
Having brakes on the 3k axle you are running is a good thing. No matter what you stuff under it the legal GVWR is 1200 lbs.

The best advice for people modifying a trailer for a particular use is go use it, settle on the what you will be hauling then go get it weighed loaded. At that point they can make an educated decision as to what they may want/need to do to the suspension, if anything.
/thread hijack
 

rnArmy

Adventurer
Thank-you.

Good catch.

Yes; I did originally swap out my factory slipper springs for some 2-leaf 26" long springs rated 575lbs each. They worked fine, but then I started adding weight to the trailer (quite a bit actually - a big jump) and thought they might be too soft. So I increased to some 3-leaf 26" long 850lb each rated springs. They worked fine, but I wanted to see if some slightly softer springs would work better (plus I guess I just can't leave well enough alone). This trailer is a rolling experiment/test bed; always being tweaked. And I keep adding weight it seems to the trailer.

Like I said; the 850lb each springs worked fine, but I thought I'd try some 3-leaf 28" long 740lb rated springs. These were 2" longer (28" vs. 26") , so the center pin was placed at the outer edge of the spring plate on top of the axle (vs. in the center as they normally are) to shift the axle closer to where it started. And then the trailer spent time being pounded off-road (the suspension took a beating). One spring finally snapped at the edge of the spring mount (remember; this is also where all three holes were for the center pin), and the other spring was getting close to breaking. This was the first time I had a spring break, and I think it was mainly flexing at the center pin (and the abuse the springs were taking). Top spring is the surviving 740lb spring (you can see the by the center pin where it was flexing and getting ready to break); the bottom spring is the new 975lb (each) spring before I modified it.

trailer spring broke.4.jpg

So the next step up was the 4-leaf 28" long 975lb (each) springs. I could have gone back to the 3-leaf 26" long 850lb (each) springs, but then I'd have to move the rear shackle mount on the frame forward 2" (where I had started originally when I got rid of the slipper springs), and the tire wouldn't be as centered under the fender as I'd like.

On these 4-leaf 975 springs I had the center pin holes re-drilled staggered so the axle is still in the same place as with the 740lb springs, but the center pin ultimately ends-up in the center of the spring plate. And I trimmed a little off the ends of the spring ends (obviously not the spring with the eyes on each end) which in some way will decrease the 975 rating. I've also incorporated factory Jeep TJ bumpstops to help with over-flexing the springs (which may have help lead to their demise). I have not given this new set-up a workout yet, so I can't say yet how well this works.

Trailer repair.13.jpg

I will stop hijacking this thread - I started a new thread related to this subject.

Harbor Freight (type) Trailer Suspensions | Expedition Portal

Please PM me if anyone has any questions on changing out their factory HF springs (or check-out the link above) for some better performing aftermarket springs. It really is worth it. The OP really did a nice job on his trailer; I just think he could make it better getting rid of the factory slipper springs.
 
Last edited:

Roam.Wild

Active member
Not to be critical in the least, but it would seem that you most certainly have the skills. What made you buy the northern tools base trailer, to cut it up, and build a bigger trailer? Wouldnt it have been just as cost effective to build it out from scratch? When i built my teardrops frame, I had roughly the same money, and have it to my personal design. You have mad skills in your fab work :cool::cool:

I thought it would be faster starting with a prebuilt frame that I only needed to beef up, and it wasn't at all. I could have saved a few hours easily by starting from scratch. I am currently building a 2nd one that is a bit larger and more heavy-duty, and I started totally from scratch this time, I already like it much better than starting off with the Northern Tool frame.

When you factor in all the extra steel and lumber he's added plus the future 100 lb + RTT and current gear, this trailer may ride just right. In 30+ yrs I've had 5 trailers and never once did I feel the need to change the springs for a better ride. A trailer is designed to carry load X, and everyone that is building/using it will have different loads that can and will change to the days needs. It's better to be oversprung than under lest we start snapping leaves.

While its pretty bumpy on the trails, which I expected, its not even noticeable on the roads. Havent gotten to take it out yet with the RTT, but hopefully between that and dropping the tire pressure down to 15psi it will help a lot more!

Very nice!

You'll like your trailer even more if you swap out the factory slipper springs for some longer springs with a shackle at the end. It is a simple bolt-on affair. The factory slipper springs are way too stiff, and your trailer will be bouncing all the time.

It is pretty bumpy, hoping the RRT will weigh it down some so it doesn't bump around so much next trip! I am also going to drop the tire pressure down even more than I did last time, around 15 psi I think will be good. Springs are the next step though
 

rnArmy

Adventurer
One nice thing about using a HF or Northern Tool trailer frame, is that you get a bill of sale. At least in WA, I could just take that bill of sale to the tag office and get a tag for my trailer. It is more difficult in some states to get a tag on a home-made trailer frame.

And yes; lowering the trailer tires to 15 psi will help; better springs will help also.
 

GlennA

Adventurer
Agrre on the proper documentation. When I went to register my home built, the DMV wanted receipts for everything used in the build. Not only the major components, but the paint, nuts bolts etc. I ended up buying a used HF/Northern Tool trailer for $100 with paperwork. Transferred VIN tag to home built. All is good again.
 

Roam.Wild

Active member
One nice thing about using a HF or Northern Tool trailer frame, is that you get a bill of sale. At least in WA, I could just take that bill of sale to the tag office and get a tag for my trailer. It is more difficult in some states to get a tag on a home-made trailer frame.

And yes; lowering the trailer tires to 15 psi will help; better springs will help also.
Agrre on the proper documentation. When I went to register my home built, the DMV wanted receipts for everything used in the build. Not only the major components, but the paint, nuts bolts etc. I ended up buying a used HF/Northern Tool trailer for $100 with paperwork. Transferred VIN tag to home built. All is good again.

Yeah having a title is nice when I go to sell it, luckily here in SC no tag is required! Crazy they wanted receipts for the paint and stuff!
 

high-and-dry

Active member
maryland is the same, anything you buy to make the trailer they want to know about. And they want receipts for the stuff you can give them. Its all about the tax,pay salestax to buy the parts, pay an "excise" tax on the valueof the material.

For my trailer is was about 120 bucks more in taxes
 

GlennA

Adventurer
Yeah having a title is nice when I go to sell it, luckily here in SC no tag is required! Crazy they wanted receipts for the paint and stuff!
I was actually living in SC when I encountered this. Even though no tag is required in-state, if you leave SC with the trailer in tow, it is supposed to be tagged. The only time I had an issue without a tag was in AL. BTW, you can get a permanent tag in SC for $75.
 

jays0n

Adventurer
Looks great so far and you definitely you have some skills! Did I miss you mentioning that you will or won't ever be putting a RTT up there? Speaking from experience off road with my trailer when it was originally built tall like yours, it spent a lot more time than I was comfortable with on 1 wheel. My trailer has a lot more weight total and a lot more down low (2 batteries, 12 gallons of water, 33" tires, etc) and is wider but it still didn't like the weight of a RTT, awning, solar panel up that high. The new rack lowered it about 16", which made a HUGE difference off road. If you're planning to take this off road much you might need to think about that. Keep up the good work!
 

RubberBandClip

New member
Looks great!

I'm in the design phase for a very similar trailer. Can you throw some dimensions to help a brother out?

Length (front to back) of the box
Ground to top of box
Ground to top of RTT platform

I've got almost the same design down on paper but can't shake the feeling I'm making it too tall too!
 

Roam.Wild

Active member
Some updates!
Been using the hell outta this thing this year so I decided to finally add some shocks! WAY better now and I wish I would have done it at the beginning. Ordered these shocks from Lippert and fabbed up my own brackets for them. It seriously rides so good now on and off pavement.
 

Attachments

  • IMG_9583.jpg
    IMG_9583.jpg
    592.8 KB · Views: 73
  • IMG_9582.jpg
    IMG_9582.jpg
    715.2 KB · Views: 66
  • IMG_9581.jpg
    IMG_9581.jpg
    636 KB · Views: 57
  • IMG_9580.jpg
    IMG_9580.jpg
    782.6 KB · Views: 64
  • IMG_9579.jpg
    IMG_9579.jpg
    840.1 KB · Views: 70

Roam.Wild

Active member
Also I decided to add a slide in the rear to make it easier to get things in / out. These were the slides I used. The frame is just made from leftover wood that I used to make the main body. I also ordered these doors to replace the ones on there now, hoping to get them replaced this weekend!
 

Attachments

  • IMG_0153.jpg
    IMG_0153.jpg
    825.3 KB · Views: 51
  • IMG_0151.jpg
    IMG_0151.jpg
    1,003.3 KB · Views: 50
  • IMG_9955.jpg
    IMG_9955.jpg
    440.9 KB · Views: 49
  • IMG_9954.jpg
    IMG_9954.jpg
    458.9 KB · Views: 50

Roam.Wild

Active member
And here's 2 random pictures from last week, we spent 5 days in Shenandoah National Park and it was a blast!
 

Attachments

  • IMG_0180.JPG
    IMG_0180.JPG
    1.7 MB · Views: 56
  • IMG_0219.JPG
    IMG_0219.JPG
    1.9 MB · Views: 63

Forum statistics

Threads
188,026
Messages
2,901,320
Members
229,411
Latest member
IvaBru
Top