70' W500 Dodge

Rat Rods Rule

Help Support Rat Rods Rule:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Whoa!

5 years since I posted anything on this build. Truth is, up until last summer I'd been driving it from time to time just for fun. Then, I hatched a plan to restomod it. My vision was to make it easy and comfortable to drive, so anyone could drive it. This would entail Power Steering and an Automatic Transmission to make it easy and a new suspension to make it comfortable. So last summer we started by removing the rear leaf springs (that were rock hard) and working to fabricate a coil sprung 4 link rear suspension. So we bought a box of brackets from Barnes 4WD and imagineered a way to hook everything to the truck. Then it just sat there all tacked up and ready to weld just waiting for someone to take the initiative to pull the parts off the frame and bring them into the shop to weld them up. Today was the day.

attachment.php



attachment.php


The upper spring bucket that still needs to be finished.

attachment.php
 

Attachments

  • IMG_9456.jpg
    IMG_9456.jpg
    83.5 KB · Views: 33
  • IMG_9460.jpg
    IMG_9460.jpg
    129.9 KB · Views: 36
  • IMG_9454.jpg
    IMG_9454.jpg
    175.9 KB · Views: 39
When I started this, I knew nothing about a triangulated parallel 4 link rear suspension. Today I know just slightly more than nothing. But what I did learn is that there's a basic set of rules to follow when setting one up. One of the first rules is the links, aka radius arms should be as close to level as possible with a maximum of 7 degrees. On this truck the axle is so far below the frame, had we mounted the lower link brackets to the frame, the lower links would have been too steep. So, we built proxy frame members to drop the radius arm bracket 6 or 7 inches.

attachment.php


And hung them from C channels that straddle the Dodge frame.

attachment.php


These are the upper links. The lower link brackets can be seen below.

attachment.php


After hanging and lining everything up.

attachment.php


I put these side plates on that Dale made. They'll add some strength and make it look like the lower brackets are part of a belly pan type deal.

attachment.php
 

Attachments

  • IMG_9456.jpg
    IMG_9456.jpg
    83.5 KB · Views: 21
  • IMG_9471.jpg
    IMG_9471.jpg
    160.3 KB · Views: 25
  • IMG_9469.jpg
    IMG_9469.jpg
    116.6 KB · Views: 23
  • IMG_9472.jpg
    IMG_9472.jpg
    151.7 KB · Views: 25
  • IMG_9473.jpg
    IMG_9473.jpg
    144.2 KB · Views: 24
Can't tell in the pic, are these touching the cross brace? if not they need to be.

attachment.php
 

Attachments

  • IMG_9469.jpg
    IMG_9469.jpg
    119.4 KB · Views: 19
The second rule I learned was that the recommended separation between lower and upper link pivot points should be no less than 25% of the tire diameter. Given the truck has 44" tires, that's 11" and that's why the upper link brackets ended up so high between the frame rails. The main job or purpose of the upper links is to control axle wrap under both acceleration and braking so there's a lot of pushing and pulling on the upper link brackets. I'd assume this is where the 25% rule comes from. As OI pointed out, there needed to be more support on the upper link brackets.

attachment.php


First I cut this piece using 2"x 2" x .187 angle

attachment.php


Then I drilled mounting holes in it

attachment.php


Then I transferred and drilled holes in the C Channel piece

attachment.php


Next, I tapped the holes. This is where I always question choices I've made in life.....lol I hate hand tapping but for this, it's the correct way to do it.

attachment.php


Bolted it all back in the truck for a test fit and everything lined up good. That almost never happens lol

attachment.php


attachment.php


Then welded it to the brackets. I'll weld the underside next time I pull it out for whatever reason.

attachment.php


attachment.php
 

Attachments

  • IMG_9477.jpg
    IMG_9477.jpg
    168.6 KB · Views: 33
  • IMG_9478.jpg
    IMG_9478.jpg
    162.5 KB · Views: 32
  • IMG_9481.jpg
    IMG_9481.jpg
    120.1 KB · Views: 31
  • IMG_9480.jpg
    IMG_9480.jpg
    177.9 KB · Views: 31
  • IMG_9484.jpg
    IMG_9484.jpg
    132.6 KB · Views: 30
  • IMG_9482.jpg
    IMG_9482.jpg
    139.1 KB · Views: 31
  • IMG_9485.jpg
    IMG_9485.jpg
    147.8 KB · Views: 30
  • IMG_9486.jpg
    IMG_9486.jpg
    103.6 KB · Views: 29
  • IMG_9487.jpg
    IMG_9487.jpg
    108.6 KB · Views: 30
I had never heard the 25% of tire height rule. Does it matter what portion is above or below the axle centerline? Or is it just the spread?
 
Curious why you bolted the angle iron in place rather than welding it?

Just so it can be removed. Also, I tend to believe bolts are stronger than welds but, I could be wrong.

I had never heard the 25% of tire height rule. Does it matter what portion is above or below the axle centerline? Or is it just the spread?

Come to think of it, the video I watched to learn enough to pull this off was about building rock crawler 4 links. So it may not be a rule for everything. I'm pretty sure it was from the axle center line which is pretty much the location of our lower link at the axle.

Here's a photo of a 4 link on a 2012 F450 cab and chassis.. The tires are probably 31" diameter or so and the spread looks to be at least 25%. (I'll have to measure it because now I'm curious) I would think the bigger the spread, the stronger.

attachment.php
 

Attachments

  • IMG_9474.jpg
    IMG_9474.jpg
    201.1 KB · Views: 29
Today I worked at building a cross member to tie the front of the proxy frame rails together. The top of the lower link brackets have big shelves on them that will work perfect for welding it to.

attachment.php


Will need to build a half hoop to clear the driveshaft as seen above. Yippie.

attachment.php


1/4 x 3 flat stock should work

attachment.php


Times 2

attachment.php


Test fit

attachment.php


Tacked and set in place. I'll finish it tomorrow if I have time.

attachment.php
 

Attachments

  • IMG_9502.jpg
    IMG_9502.jpg
    157.6 KB · Views: 24
  • IMG_9500.jpg
    IMG_9500.jpg
    205.8 KB · Views: 22
  • IMG_9503.jpg
    IMG_9503.jpg
    154.7 KB · Views: 23
  • IMG_9505.jpg
    IMG_9505.jpg
    158.8 KB · Views: 23
  • IMG_9506.jpg
    IMG_9506.jpg
    117.9 KB · Views: 23
  • IMG_9507.jpg
    IMG_9507.jpg
    149.3 KB · Views: 23
Today; After welding the 1/2 hoop to the flat stock pieces I got it all clamped up and tacked it in. Then I went to remove the whole assembly so I could bring it inside and finish welding everything and paint it but, it was just too heavy and I got it stuck. So, I left it until tomorrow when I can get some help.

attachment.php


attachment.php
 

Attachments

  • IMG_9509.jpg
    IMG_9509.jpg
    164.8 KB · Views: 22
  • IMG_9510.jpg
    IMG_9510.jpg
    146.9 KB · Views: 19

Latest posts

Back
Top