Sinking Creek 4WD Association

Making a new thread for this in technical for more discussion on cheap suspension design.

Summary: Spring shackle flip or traction bars to fix wheel hop? Which is better/cost efficient

So to start my ghetto Ideas off, my rear axle (dana 70 2u) is attached to my truck with a tension shackle leaf spring set up and has a surprising amount of flex for being essentially stock. The main problem with the design is it came with a 3" spring perch from factory which proved to be the weak point in the suspension at Rausch Creek last month. The perch had come out from between the spring and the axle and forced me to limp my truck back to camp where a whole cluster fuck of sketchiness occurred to get everything back together working right. Another Issue with the spring perch and the large tires is that there is a ton of wheel hop. I've had a few ideas to help this but the main two Ideas are to either convert the leaf spring to a compression shackle system and get rid of the spring perch, or build a traction bar for the rear end.

Shackle flip:
Ruffstuff specialties sells a weld in shackle flip kit for around $180 and would allow me to adjust the height of the rear lift by the shackle length (Don't worry I wont go Rhino crazy) and would also improve pinion angle. I would have to modify the spring perch on the axle itself or build my own but that is not a hard feat.

Traction Bar:
One of the issues with the 2nd Gen dodges is that the fuel tank comes down right next to the driveshaft so its always getting hung up by rocks so I plan on changing it to something else that can go in the bed of my truck between the frame rails. Ironically, the gas tank is currently the only thing protecting my driveshaft from being destroyed so without it there my driveshaft is exposed; this is why I was throwing around the Idea of adding a traction bar right next to the drive shaft to help with axle wrap and protecting the driveshaft at the same time. I already have the materials except for the bushings so this would be the cheapest option of the two and also solve my driveshaft problem. For the spring perch issue, I plan on welding a flat plate the the spring perch itself and the axle, allowing me to bolt it to the axle so it can't shift around at all and come loose.

Now for the main reason for this thread...

I've done some research but I personally have no experience with either of these options so I wanted to see what you all have done/ recommend. Id like to make this thread about more of the design and functionality of each option rather than just the application to my truck. If there are other cheap suspension tips/tricks out there feel free to comment. The more ghetto the better (to an extent...I don't want y'all recommending I nail 2x4's together as a lift block)

Spring shackle flip kit:
https://www.ruffstuffspecialties.com/ca ... NFLIP.html


Pirate4x4 Traction bar thread:
https://www.pirate4x4.com/forum/toyota- ... t-ups.html

I did a shackle flip on my Dodge way back when. It came from BDS suspension, no idea if they still sell it. Worked pretty well. I don't remember having much problems with wheel hop before or after though.

Didn't have to do anything on the axle other than a zero-rate spacer to get the axle re-centered in the wheel well, but if you're getting rid of the bed that probably doesn't matter.

No experience with either but I feel like traction bars are just a band-aide for the real issue. I think the better idea is to flip the shackle and remove "spring perch" lift block.

From my understanding traction bars fight against spring wrap which happens to all leaf spring applications to a certain degree. The more leverage on the spring, the more wrap. So having a 3" spring perch between the axle and the spring basically adds that much more leverage. A traction bar just keeps the axle from wrapping and the pinion pointed at the correct angle. I wouldn't really say its a band aid really since for most applications its a permanent fix for high leverage/ high torque applications.

But you should probably fix the root of the problem, the block that causes additional spring wrap. If your still having issues then go add traction bars. If you were building a drag truck or something I'd say traction bars for sure but I don't see why you would be generating enough torque to justify it.

Now if your talking about cheap and fast solution, you said you can make traction bars so that would be your sketchy solution and should in theory fix your issue.

I might do both anyways just because I want the added protection for my driveshaft, Would it be the worst thing in the world to just run two bars from the bottom of my axle to the skid plate? Haven't really seen it done before but with my low pinion 70 and the stupid long wheel base it might not be the worst idea. This would help with axle wrap going forward, just not back, but that hasn't really ever been an issue.

Ditch the tall spring perch and custom build a perch that sits close to level with the top of the axle tube and make it longer than stock. The more surface area the perch has with the springs the better. This should reduce the leverage on the springs and help a lot with axle wrap. I have always wanted to build a custom perch that uses bolts to clamp the springs to the axle and get rid of the u bolts. From the little reading I have done it seems like it works well but I dont know if its worth it or not.

alk1174 wrote: ↑Tue Apr 09, 2019 7:42 am Ditch the tall spring perch and custom build a perch that sits close to level with the top of the axle tube and make it longer than stock. The more surface area the perch has with the springs the better. This should reduce the leverage on the springs and help a lot with axle wrap. I have always wanted to build a custom perch that uses bolts to clamp the springs to the axle and get rid of the u bolts. From the little reading I have done it seems like it works well but I don't know if its worth it or not.

Yeah Ill try that, the U- bolts moving around are the reason that the axle shifts around. There not being any bushings left on the springs might be a factor too haha.

Neither, buy my coilovers

alk1174 wrote: ↑Tue Apr 09, 2019 7:42 am Ditch the tall spring perch and custom build a perch that sits close to level with the top of the axle tube and make it longer than stock. The more surface area the perch has with the springs the better. This should reduce the leverage on the springs and help a lot with axle wrap. I have always wanted to build a custom perch that uses bolts to clamp the springs to the axle and get rid of the u bolts. From the little reading I have done it seems like it works well but I dont know if its worth it or not.

Ruff stuff and Barnes has a decently cheap kit that does exactly that. A long spring perch that sits close to the axle tube and replaces u bolts with 5/8” grade 8 bolts. I got a pair for the rear of my 85 runner, but have yet to see how well it works.

Gus sold me a rear truss for my dana 70 so i think i will o something along those lines. truss will add enough height that i should be able to keep same ride height without a lift block. I still have a lot of other stuff to deal with in the meantime but i will post pictures when I get there