Silence The SuperDuty Springs!

[Gary Lewis]

I need some help, folks. My 2004 or newer SuperDuty springs, installed rear-end forward with a reverse shackle kit, clang on bumps if not "restrained", and I'd like a good and permanent solution - which is where you come in 'cause I haven't found one.

In the pic below, which is the current situation, you can see four things:

• Gap: The red arrow points to a gap between the springs because the lower spring wraps loosely around the upper spring such that the gap continues up on top between the two springs. And w/o some restraint the lower spring is free to slap into the upper spring at its eye, making a whole bunch of noise on bumps.

• Nylon Pad: The green arrow points out the nylon pads that came from the factory to allow the springs to move with respect to each other w/o making noise. Those pads were worn to nothing when I got the springs, but even replacing them did little to nothing to reduce the noise.

• Spring Liner: The yellow arrow points to some spring liner material that I had left over from Dad's truck. I put it in with an industrial spray adhesive, but even it doesn't quieten the noise as the noise appears to come from the ends of the springs banging together.

• Restraints: The blue arrow points to homemade restraints, aka hose clamps, that made a big difference in the noise. However, 268 miles of corrugated gravel road loosened them up enough that some of the noise came back. I probably got more than a full turn on the screws on all four of the clamps (2/side) after the trip, so .

So I'm looking for a better approach. I've done a lot of reading and I've found TSB 99-16-3, but that only applies to 1999 & 2000 SuperDuty trucks, and even then it addresses a squeak and not a clang. The fix specified in the TSB is to install kit #1C3Z-5B302-AA, and all of this as well as pics of the kit are discussed here: Squeak Squeaking Front Leaf Springs 1999 2000 Kit Insulator Repair Kit TSB 99-16-3.

But I don't think that is going to solve my problem and am looking for suggestions. Stronger clamps/restraints might work, but in reality the springs are supposed to be able to move independently so that's not the best approach. A rubber isolator just the right shape that would fill the gap?

Was there something there from the factory on the SuperDuty trucks? Or, maybe with that to the rear there's always pressure to keep things from clanging? http://www.garysgaragemahal.com/uploads/6/5/8/7/65879365/thinking-26_orig.jpg

Help! http://www.garysgaragemahal.com/uploads/6/5/8/7/65879365/waving_orig.gif

[grumpin]

Can you pry them apart and put more nylon pads in there?

And hopefully the pads will be tight enough to stay put.

[ArdWrknTrk]

It's not a bug, it's a feature.

While you may not like the noise this is a truck, and this is how a properly designed progressive leaf spring works.

My thoughts go to something like Sugru or some other self curing silicone paste to be packed in the gap between the outer and inner shackle bushing eyes.

Maybe a product from Smooth-on?

They seem to sell a wide range of viscosities and cured durometer RTV's.

Maybe their PMC series, or Poyo silicone moulding paste?

They do have some super tough urethanes for conveyor belt repair, but those are liquids and cure too quickly for what you're trying to do.

You certainly don't want anything that is stiff enough to restrict much motion, nor soft enough that it will just squish out.

[ArdWrknTrk]

Can you pry them apart and put more nylon pads in there?

And hopefully the pads will be tight enough to stay put.

Dane, I think Gary's complaint is the spring loop clacks against the bushing eye when the suspension loads or unloads.

 

[Rembrant]

Gary,

A set of proper leaf spring clamps would work better than hose clamps, wouldn't they? Like these below:

https://www.jegs.com/i/JEGS/555/60884/10002/-1

https://dirtyhookerdiesel.com/i-14902715-dhd-600-417-dhd-leaf-spring-clamp-set-of-4-2001-present-duramax-diesel.html

I have regular leaf spring clamps on the back of both trucks...you know the spring shop rubber lined style that you just bend the tabs over? You could use those also...squeeze them tight with a C-clamp, bend the tabs, and tack them in place so they won't/can't loosen.

Just spit balling Gary...ha, I've never owned anything with leaf springs up front (Edit...not including Jeeps).

 

[Gary Lewis]

Dane, I think Gary's complaint is the spring loop clacks against the bushing eye when the suspension loads or unloads.

Dane - Jim is right, my complaint is the almost constant rattle that is created by the loop hitting the eye. Any little bump causes it, and washboard roads make it sound like the front end is going to fall off. But the hose clamps help a whole bunch because they limit the ability of the lower spring, which is otherwise not constrained at all, from hitting the eye.

Jim - Interesting idea. Create a mold by positioning the springs, probably with a clamp around them to maximize the gap, put walls on the sides to prevent the stuff from running out, and pour the liquid in.

The PMC Series looks like it would do it, and more specifically PMC 770, 780, or 790. However, I'll need to do some reading to figure out which one, and what "Shore Hardness" I need. And I'll bet the hanger would keep the cured rubber in the joint.

I'm still struggling with how the "progressive" nature of the springs works. As the weight comes down on the spring does the gap at the very front get smaller? If so you wouldn't want to prevent that from happening.

Thinking of another approach, what if I slid the spring liner around the curve so it took up some of the gap and then used a clamp? That way I wouldn't have the metal-to-metal clang but there would still be movement possible.

[Gary Lewis]

Gary,

A set of proper leaf spring clamps would work better than hose clamps, wouldn't they? Like these below:

https://www.jegs.com/i/JEGS/555/60884/10002/-1

https://dirtyhookerdiesel.com/i-14902715-dhd-600-417-dhd-leaf-spring-clamp-set-of-4-2001-present-duramax-diesel.html

I have regular leaf spring clamps on the back of both trucks...you know the spring shop rubber lined style that you just bend the tabs over? You could use those also...squeeze them tight with a C-clamp, bend the tabs, and tack them in place so they won't/can't loosen.

Just spit balling Gary...ha, I've never owned anything with leaf springs up front (Edit...not including Jeeps).

Cory - Thanks. The clamps were the next thing to think about. While the ones you listed would work, if tightened down they would prevent the springs from sliding with respect to each other, which I think is necessary as the load changes. And if they were left loose they'd rattle and might shift down the springs.

The "spring shop rubber lined style" might be the ticket. But by "tack them in place" I assume you meant put a piece of bar across the tabs and tack that in place so they couldn't open up?

I think the key is to provide enough restraint that the springs can't bang into each other but not so much that they cannot slide. And that takes just the right balance or the clamps themselves will rattle and move.

 

[Rembrant]

The "spring shop rubber lined style" might be the ticket. But by "tack them in place" I assume you meant put a piece of bar across the tabs and tack that in place so they couldn't open up?

I mean like these clamps below Gary, this is what our local spring shops sell:

https://www.npdlink.com/product/clamp-leaf-spring/104805

I just meant to weld them to themselves...once you bend a tab over, you could squeeze it in place with a C-clamp, and tack it in place. You'd squeeze the clamp in place anyway...and hammer the tabs over normally, but take the extra step to weld the tabs down.

 

[Gary Lewis]

The "spring shop rubber lined style" might be the ticket. But by "tack them in place" I assume you meant put a piece of bar across the tabs and tack that in place so they couldn't open up?

I mean like these clamps below Gary, this is what our local spring shops sell:https://www.npdlink.com/product/clamp-leaf-spring/104805I just meant to weld them to themselves...once you bend a tab over, you could squeeze it in place with a C-clamp, and tack it in place. You'd squeeze the clamp in place anyway...and hammer the tabs over normally, but take the extra step to weld the tabs down.

Yes! Those should work nicely!

 

I've actually not seen those before. They fit the bill in many ways, including having the rubber pads and being very adjustable.

 

The only issue is that those are for 2 1/2" springs and I think the SD springs are 3", but I'll confirm that this afternoon. (We are finishing the painting of the guest bath this afternoon, but I have to go to the shop to get the roller and pan, so can check then w/o getting caught. ) But I'm sure there are ones just like them for 3".

 

Here's the pic to remind me of what I'm looking for. And with the spring liner where it is the clamps won't be able to go anywhere.

 

[Rembrant]

Yes! Those should work nicely!

 

I've actually not seen those before. They fit the bill in many ways, including having the rubber pads and being very adjustable.

 

The only issue is that those are for 2 1/2" springs and I think the SD springs are 3", but I'll confirm that this afternoon. (We are finishing the painting of the guest bath this afternoon, but I have to go to the shop to get the roller and pan, so can check then w/o getting caught. ) But I'm sure there are ones just like them for 3".

 

Here's the pic to remind me of what I'm looking for. And with the spring liner where it is the clamps won't be able to go anywhere.

 

Gary,I know they’re available in 3” wide. Couple good things…you can control how tight you clamp them, and you could always use thicker rubber pads in them if you wanted to.