How To Build the Monster Rear Suspension for your 77-93 Dodge

THE RIGHT WAY!

 

*Disclaimer* This is provided as a free service and for information purposes only. There is no warranty, promise or responsibility given by us to you that if you try this all will go perfectly. It all has to be EXACT!!! Not close, not pretty good. EXACT! Also, I didn't go into cleaning the metal before welding, grinding down edges for full penetration, stepping up hole sizes in the drill press or the like. If you need us to tell you that stuff DON'T TRY THIS AT HOME! Best to take the drawings to a welder and have them make these for you. Now that you are thoroughly paranoid about screwing it up lets proceed.

I think the single best thing I ever created was the Monster Rear Suspension. It used massive rear springs and offers exceptional flex and ride quality. The only thing you could run that would be better than this would be coils and 4 link. For what a single coil over costs you can have upwards of 20" of REAL travel and all the ride quality you can handle. It also offered the ONLY 8" all spring lift option for Dodge trucks. It doesn't get any better than that, huh? Massive no block lift that actually travels and ride better than stock and done on the cheap!

Here's what it takes to do this job.

What materials you'll need

  • 2 - 6x8.375" 3/8" steel plates
  • 2   1 1/2" 3/8" bar stock about 3 3/4" long
  • 2   1 1/2" 3/8" bar stock exactly 2 3/8" long
  • 4    4"x 2 1/2" triangles out of at least 1/4" steel plate.
  • 16   1/2" X 1 1/2" Grade 8 Bolts
  • 16   1/2" SAE Style (around 1" outside diameter) hardened washers
  • 16   1/2" Fender style( 1 1/2" outside dia" at least) thick washers. You want something with some beef as this will keep the bolts from pulling through the frame.
  • 2   5/8" x 4 1/2" long grade 8 bolts, fine thread
  • 2   5/8" grade 8 fine thread nuts
  • 2   5/8" fender style thick washers
  • 2   5/8" SAE style washers
  • 6   3/4"OD-5/8" ID x2 15/16" long metal sleeves

The steel we got from IMS in Irvine, CA. All our bolts and such came from McMaster-Carr Supply in Sante Fe Springs, CA. 

What tools you'll need

  • Drill press and at least a 1/2" drill bit, 9/16" and a 5/8" drill bit. 

  • Band saw, plasma Cutter or some way to cut 3/8" steel plate accurately and precisely.

  • Angle grinder

  • 210 amp mig welder. You can use a big stick welder if you have one and are good with it. Tig welding would work too but with material this thick I prefer Mig or Stick personally. 

  • Big disk sander or bench grinder

Additional Parts Needed

  • 2 88-98 Chevy rear springs (see below)

  • 2 sets of Energy bushing kits, part # 3-2128

  • 2 8" rear shackles

The new 66" rear springs are the real key here. We cannot supply the springs. You will have to source those yourself. It's not hard to get them. Here are a few parts numbers you can use to find what you need.

66_rear_springs.jpg (35081 bytes)
Stock vs. the new 66" rear springs

Skyjacker - CR33S (single) for 6" of lift
Skyjacker - CR35S (single) for 8" of lift

Pro Comp - 13211 6" of lift (very soft springs)
Pro Comp - 13711 8" of lift (very soft springs)

Stock 88-98 rear springs will net about 3-4" of lift with the instructions below

You'll need to change out the stock bushings with the poly bushings listed above. The easy way to do this is to wedge a large screwdriver in the gap at the springs eye where it wraps around the old bushing. Don't go too crazy. The bushing should slide right out with little effort now. Insert the new bushings and 5/8" ID inner sleeve and set them aside while you build the rest of it.

Dimensions of Rear Flip Brackets

 

Here are links to the Adobe PDF file that has everything you need to make your own rear flip brackets for this suspension. Open it, print and use it as the template. They SHOULD be 1:1 so you can use it as your template to make your holes. Double check that your printer didn't scale it though. The '72 through around 75'ish trucks used a different bolt pattern on the frame. These brackets will not fit your truck if the shackle hangers are tipped more than about 8 degrees. You'll know this because the front and rear bottom rivets are about the same height off the bottom of the frame.

Pics to follow

Now that you have the drawings you can start to see how it lays out I hope. The plates get 4 1/2" holes where the frame holes are. The pivot hold is drilled to 5/8". These MUST BE EXACT!!! Round the corners to make it look pretty if you care.

Measure your shackles, 5/8" nut and 5/8" fender washer all together. Subtract 3/8" and this is how long you need to cut the piece of bar stock I said that was "around" 3 3/4" long. With the washers we used 3 11/16" was exactly our dimension. Yours will/might vary. The cuts have to be perfect here. We used a metal cutting bandsaw for this and it worked well. Just make sure they are straight and equal on both bars. This is critical to it all lining up right and the truck driving straight down the road.

Pics to follow

The two other holes you need to drill are for the 2 3/8" outside bolt tabs that will get welded on one end of the bar you just cut. Mark it 3/4" from one end and each side and drill a 5/8" hole there. This must be exact! Shape the end with the hole in it so that the corners won't get caught on the shackles. It also looks a lot better. Be as pretty as you want but don't take away too much material. Broke because it's too pretty ain't pretty at all!

Pics to follow

Take these two 2 3/8" tabs and put your 5/8" x 4 1/2" bolts through them. Now thread the 5/8" nut on the end so about 1/4" of thread is sticking out the end. Place this in the 5/8" hole in the plates. I don't need to tell you that there is a left and right here. Make sure they are flipped right side up!!! Place the 3 3/4" 3/8" bar under the outer tab and line it up so it's parallel with the top and bottom for the plate. This is important but not critical. Eyeballs are good enough for that part BUT make sure everything is nice and straight, square and plum. Nice right angle between the plate, the 3 3/4" bar and the outer tab!!!! Make sure the nut is firmly and squarely against the surface of the plate. This is where it can all goes wrong in a hurry. Take your time and get it PERFECT! Now you can start welding it all up. Tack the nut and tabs on all sides first, recheck that all is perfect, then crank up the heat and melt some steel! This will take a lot of heat to weld up 3/8" plate. Don't try this with a 110V welder. It won't work!

Pics to follow

After it all cools down remove the bolt and clean up all the welds. Get rid of any splatter and get it ready for more welding. Take you triangles and hold them up to the backside of the upright bar. Figure out where you want them. Spread slightly out  at the top is better for more complete support. Just be careful of the top forward 1/2" bolt holes. There isn't a lot of extra room here with the small SAE washer installed. Weld the triangles on and again, weld the snot out of them! This will be taking all the weight and force from the suspension. 

Again, clean up the welds, grind the splatter and paint. 

Now that you're done with that you just need to get the old hangers and rivets outta there, drill out the holes to 1/2", bolt the new brackets on and figure out which shackles to use. We have used Summit Racing's 88-98 Chevy drop shackles with good success before. You just have to replace the inner sleeve to fit the Dodge 5/8" bolts and drill out the other end for the 5/8" bolts as well.

The next step is to remove the front spring hangers and clean up the frame a bit. Also, you will need to remove the parking brake bracket and set it aside for later mods. You will need to drill out the forward-top hole and all 4 holes in the spring hanger to 1/2" Make sure there are no fuel or brakelines and no wiring in the way. Take 1 1/2" bolt and put it in the rear-top hole of the spring hanger. This then goes in the forward-top hole in the frame. This will space the spring eye just about perfectly on the frame to center the tire in the wheelwell. Tighten this bolt up snug so you can position the hangers to mark the other 3 holes. The brackets should be level on the frame but more importantly you need to make sure the two sides match. Measure the distance from the top of the hanger at the rear wing and the front make them match (or just a bit higher in front than in back) and you are good to go. Now mark and drill your holes. Again, exactly where they need to be!!!!! Bolt the hangers down with the little washer outside and big washers inside the frame. Torque is about 65 ft.lbs.

The parking brake bracket need to be modified a bit. Transfer the holes over about 1 1/8" and redrill the holes to 9/16". 

Cut off the excess as shown (compare top and bottom photos) and trip back the top so it doesn't hit the spring hangers anymore. Paint and bolt back on the frame. Hook the brake cables back up and bolt in the new springs. 
Here it is all installed. Make sure the short side of the springs goes in front of the axle. There isn't much difference so make sure before you set these in place,. They are seriously heavy so you only want to do this once! Torque down the u bolts and hook up the shocks. You can use 33" overall, 12" travel shocks if they are in the stock type position and get max travel. The 8" suspension needs a 14" travel shock. 

Shaggy's sold it with the U bolt flip as well to complete the package. That's another tech article though. 

 

 

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