In out last session, we started installing the rear suspension for the ’48 Ford. If you thought that was exciting, we have some more cost saving ideas and a full explanation on how to set up the rearend. Being a shoestring budget-build, we are always looking for the cheapest way out – so that of course means we will not be a Dana or a Ford 9-inch.

Our first stop is invariably a recycle yard, not a salvage yard, but a true recycle yard, because they sell stuff by the pound. The real key is to find out which day they are gonna crush, and go before just before that. You can get a solid deal by shopping this way. At current steel rates, a rearend will be in the 50 – 60 dollar range at one of these recycle yards.

A lot of cities also have pick-a-part yards, and rearends are pretty cheap there as well. We have also seen rearends on Craigslist go for between 50 and 100 dollars. These of course will not be posi-trac-filled rearends, and more likely will be out of an old van, truck, or full-size car. For a low budget hot rod, these will work just fine, and keep your cost low.

A few things to keep you out of the woods however would be as follows:

  • Check to see that it turns free and there’s not a ton of slack when you rotate the shaft.
  • Check to see that it has no leaks and if it has a plug check for level to see if it’s been run dry.
  • Pull a hub and check brakes. If it has a lot of wear left on the brake shoes that’s a bonus and also let’s you know someone has kept up with it.
Rat rod

Choosing the right rearend for your rod is an art. You must consider the front axle when picking the rearend.

The reason we say brake shoes is because in this price range you’re not likely to find a disc brake-equipped rearend. Another consideration is the measurement from backing plate to backing plate. For example; an S10 or Ranger rearend will measure in the low 50-inches. An old van or full size truck rearend will measure 60-inches.

The width of the rearend plays a critical roll in the stance of your rod. If you’re building an open fender rod like we are, you want the rearend wider than the front axle. There’s at least 6-inches difference in the width of an S10 rearend and a ’69 Dodge truck straight axle. It looks pretty freaky to have the rearend more narrow than the front axle (just saying). On the other hand, Chevy straight axles are pretty narrow, and this would be a good marriage for that narrow rearend. Select a rearend with your front axle in mind.

Getting Back To It

Now that some housekeeping is out of the way, we will continue where we left off. Our frame is sitting on four 2 x 8-inch wooden blocks that are 12 inches long. This gives us our ride height. A 2 x 8-inch plank measures 7 1/4-inches wide, and once the drivetrain is in, this will settle 2 inches, giving us a total ride height of 5 1/4-inches. If you want a different ride height, then use the same formula. For a 9 1/4-inch ride height use a 2 x 12-inch board.

rat rod

Set the frame on four 2 x 8-inch wooden blocks for a total ride height of 5 1/4-inches.

With the frame on blocks, you can easily roll the rearend up under the tail section. In the case of this 48 Ford cab, we knew the rear tire being used, and the distance we wanted between tire and cab corner. As we discussed when building the frame, you may be using a longer bed or it may be a coupe of sedan you’re building, so this measurement would be different. One thing is certain: once the rearend (with tires) is tucked up under the tail section, you will get a real good visual of where you want it to sit.

rat rod

The rearend can be rolled under the tail section and blocked to prevent movement.

Once all of the calculations are done, you begin to square the rearend up. Measure from side to side and front to back. A stationary point on each side of the rearend to the front of the frame will put you right on the money. At this point, put blocks in front and back of each tire to prevent movement.

rat rod

Hold things in place by tack-welding rebar from the frame to the rearend.

Holding Things In Place

As we discussed in the last episode covering the rearend, welding Rebar from the frame to the rearend helps keep things in place. We previously discussed making traction bars and a panhard bar for the rear suspension, but wanted to clarify a few things. When it comes to the springs, you can get away from some of these other components when using leaf springs, but in most cases, the amount of room you have to work with is very limited. For this reason, we always run coilover springs, which are very expensive, or just plain coils.

rat rod

We started with traction bars made from some of the left over material from our frame construction. One end was bolted to two ears welded to the bottom of the rearend and the other end bolted near the bottom of the L kickup. A piece of pipe to fit snug over a 1/2-inch grade-8 bolt was drilled and welded into the frame for extra support.

We then welded two ears to the opposite side of the rearend to mount shocks and mounted the top of the shocks directly to the frame. The same method of using a sleeve bored and welded into the frame will give extra support to your bolts.

Four our ’48 project, we found some $5.00 coil springs at a recycle yard that were taken off of the rear of a small compact car. You want the lightest coils possible, because there is little weight to these rods. With heavy coils, the ride will rattle your teeth. The total weight of one of these  roadsters is around 1,500 pounds, and 850 of that is the engine and transmission – in the front. Therefore the lighter the suspension, the better the ride.

We made the anti-sway bar and panhard bar from 3/4-inch gas pipe. A 1/2-inch Heim joint works really well to make these bars adjustable. The nut on a 1/2-inch Heim measures exactly 3/4-inch,and slips perfectly into the pipe. A second nut will serve as a jam nut and give you adjustment if you need it.

About The Gas Tank

We were able to find a spot for our battery tray, but the gas tank proved to be more difficult. With the limited space, we were left with only one option of putting it in the 12-inch opening between the back of the frame and the reared. We took a gas tank from a Farmall tractor, because those tanks sit pretty flat, and turned it on its side. This of course meant blocking the filler neck, and mounting it on the tank’s side instead. It also meant adding a connector for a gas line on the other side of the tank, which is now the bottom.

Two more pipes were constructed the same way to serve as upper mount bars. In this case, ears were welded to the top-side of the rearend left and right. We welded these to the cross piece of 2 x 3-inch support welded in between the top of the two L kickups. These upper mounts keep the rearend from rolling up when you floor it.

With that complete, we could now knock the temporary rebar jig loose and still keep everything square and check travel. The 4-inch pipe inside the coils gives us a lot of travel, and the ability to remove the rearend if we ever need to.

As discussed in our last episode, you must check the pitch of the driveshaft. It should have 6 degrees of pitch. In our case we knew our engine and tranny would be sitting a lot higher than the rearend. We took a straight edge and calculated where the tailshaft would sit in relation to the rearend. In your case you may want to pitch your rearend up to accomplish this same 6 degrees.

We used an old gas tank from a Farmall tractor to fit in the tight space of our frame.

 

It doesn’t matter how you come up with the 6 degrees, as long as you do come up with it. Without it, you will knock U-joints out left and right.

In our next installment, we will get into the front end and all of its parts. You can check out Tommy Ring’s other work and products at Ring Rods Hot Rod Shop.