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Posted

Ill be starting my vibration journey monday when i drop it off. RCSB, was smooth then hit 5100 miles and it started. Console shakes, steering wheel shakes, passengers feel it and I feel it.

Posted

Ill be starting my vibration journey monday when i drop it off. RCSB, was smooth then hit 5100 miles and it started. Console shakes, steering wheel shakes, passengers feel it and I feel it.

Start with GM's Bunk steering like the previous generations! Your truck should have the new EPS that was designed to isolate the road and was a new totally new design offered for 2014+ They are suspect!

Posted

Melt sheet is an asphalt resin type of material, that is placed in areas know to cause noise or vibrations. What this does is absorb engine, road, driveline vibrations. It got its name melt sheet as it is usually installed at factory level before a painted car enters the ovens during paint the procedure.

 

Also known as dampening absorbing sheets.

 

Take care

I covered my entire floorboard and cab behind the rear seat with stinger roadkill as heavy as that stuff is it doesn't have enough mass to change the natural frequency enough to get it out of resonance what does help cold weather below 40 degrees all the rubber is stiffer in the colder temps and rain also mitigates the vibes when everything on the truck is wet.

Posted

Update: The dealer balanced the tires and did an alignment. They did so at their expense because they were supposed to do it the previous day but my workorder fell through the cracks. I even offered to pay because it wasn't a big deal to me.

 

Now as to the results: The vibration has been reduced significantly but not eliminated. I don't know if I'm just hyper sensitive to it now. But its now tolerable and barely noticeable at times. The toe was adjusted on the alignment. I think the need for an alignment was due to the leveling kit the previous owner installed but didn't do an alignment.

 

They said any remaining vibration is due to the tires. I'm not sure that is correct. I would love to trade someone out for some nice factory rims and tires for a day and see if it goes away.

Posted

Update: The dealer balanced the tires and did an alignment. They did so at their expense because they were supposed to do it the previous day but my workorder fell through the cracks. I even offered to pay because it wasn't a big deal to me.

 

Now as to the results: The vibration has been reduced significantly but not eliminated. I don't know if I'm just hyper sensitive to it now. But its now tolerable and barely noticeable at times. The toe was adjusted on the alignment. I think the need for an alignment was due to the leveling kit the previous owner installed but didn't do an alignment.

 

They said any remaining vibration is due to the tires. I'm not sure that is correct. I would love to trade someone out for some nice factory rims and tires for a day and see if it goes away.

Don't buy into that! Try the "u" bolt clamp in front of the axle to leaf spring. Clamp them on each side 4.5" in front of axle. See if your vibration is eliminated. The u bolt and nut kit is like $12 or so. If this improves your "ride" issues, frame beaming is happening, by installing it what this clamp is doing is making your leaf spring stronger with more density now to absorb road energy. No matter what's going on at the axle and road this energy is being sent through the frame!

 

Best of luck

Posted

Darth,

 

You have already commented that you spent 1000.00's on Axles only to find out you had a bunk "Rim" I have only commented that "I have no shakes yet, a weekend, gas and beer is all I needed to know what really is causing this problem? To each is own and I know that at any given moment my could shake! Wow.......GM has and is in process of changing the components from how the cab/frame are attached..............A little birdie told me

You're always good for a laugh.

Posted

Don't buy into that! Try the "u" bolt clamp in front of the axle to leaf spring. Clamp them on each side 4.5" in front of axle. See if your vibration is eliminated. The u bolt and nut kit is like $12 or so. If this improves your "ride" issues, frame beaming is happening, by installing it what this clamp is doing is making your leaf spring stronger with more density now to absorb road energy. No matter what's going on at the axle and road this energy is being sent through the frame!

Best of luck

Well, I doubt adding a u-bolt clamp will change the density of the material. The density is a physical property of a substance...so many lb/cubic in or cubic foot. Lead has a high density. Steel not so high. Air much, much less. And so on. Adding a clamp will not change the density. You need the change the molecular structure to change the density. The clamp will add a small amount of weight (mass). It may also increase the stiffness of the leaf spring assembly. And stiffness has a major role in vibration issues.

 

In fact, I was thinking about some of the folks that added clamps to the leaf springs and improved the vibrations and the video pinion angle changing, and I'm wondering if adding the clamps to the leaf spring reduces the wind-up of the leaf springs and hence reduces the change in pinion angle? Interesting.....

Posted (edited)

Well, I doubt adding a u-bolt clamp will change the density of the material. The density is a physical property of a substance...so many lb/cubic in or cubic foot. Lead has a high density. Steel not so high. Air much, much less. And so on. Adding a clamp will not change the density. You need the change the molecular structure to change the density. The clamp will add a small amount of weight (mass). It may also increase the stiffness of the leaf spring assembly. And stiffness has a major role in vibration issues.

In fact, I was thinking about some of the folks that added clamps to the leaf springs and improved the vibrations and the video pinion angle changing, and I'm wondering if adding the clamps to the leaf spring reduces the wind-up of the leaf springs and hence reduces the change in pinion angle? Interesting.....

Technically the density does change, the leaf springs have more surface area mating! Clamping the metal together creates more density not a taller, but rather a longer yielding run for energy to be absorbed. In its simplest form this does stiffin the leaf springs and that in turn helps absorb vibration but at a cost to ride quality!

The angle of the pinion may and should have changed, but to argue if this is why things improved would need driveline angles tested and studied.

 

Thxs

Edited by 2strokesmoke
Posted

You're always good for a laugh.

Really? You are too my friend........Post#10596 from yours truly..........Darth Vader

 

Damn, CJ, hate to hear that! Look at it this way, I have spent over $2000 on parts to find out that it was bad wheels, talk about frustration! :banghead:

 

 

 

Now I have to buy new wheels! I was on autotrader Monday myself, but I am too stubborn to give up.

 

You my friend are always good for a laugh.

Posted

Technically the density does change, the leaf springs have more surface area mating! Clamping the metal together creates more density not a taller, but rather a longer yielding run for energy to be absorbed. In its simplest form this does stiffin the leaf springs and that in turn helps absorb vibration but at a cost to ride quality!

The angle of the pinion may and should have changed, but to argue if this is why things improved would need driveline angles tested and studied.

 

Thxs

Density stays the same, density is just weight per unit volume which like wrench said is a physical property of material. Clamping the spring just changes the K value of the spring pack as a whole. The springs are designed to progressively load first spring flexes until making contact with the second then both springs flex together giving a softer ride, small bumps are handled by a single spring, larger bumps by both springs together. By clamping them you have taken the progression out making them stiffer. The clamped together stiffer pack now has less displacement per the same force applied with the spring not clamped which helps the pinion angle because the springs provide the opposing force when torque is applied to the rear end. If the goal is to control pinion angle you're better off clamping the springs together behind the axle, when torque is applied to the wheels for forward motion the pinion flange will tip up creating an opposing torque to the tires so the portion of the leafs in front of the axle compress together and the portion of the leafs behind the axle separate, by clamping the rear portion together you eliminate this separation when torque is applied. This is how the cal tracs work and why they are mounted to the rear, they also take it one step further by linking them back to the axle with a strut that loads in tension. So for controlling road input clamps in the front or rear doesn't make a difference but for pinion angle the rear is a better location, either location like 2 stroke said the trade off is going to be a stiffer ride.

  • Like 1
Posted (edited)

I had the vibration between 70 and 80mph with 78 being the worst. I added the spring clamps 4 inches in front of the axle and tightened the axle u bolts. This cured my vibration about 15,000 miles ago. I found the the clamps improved the ride in the rear of my truck. A few days later after installing the clamps I removed them and replaced them behind the axle just to see what the difference would be because at the time the clamps were a new deal we were trying. I didn't get out of my driveway good before I noticed the ride was going to be worst. I drove a few miles and soon as I got home moved the clamps back to front of the axle and has been good every since.

 

 

Forgot to add I carry about 350lbs with 3 toolboxes in the rear all the time.

Edited by southern_sierra
Posted

Density stays the same, density is just weight per unit volume which like wrench said is a physical property of material. Clamping the spring just changes the K value of the spring pack as a whole. The springs are designed to progressively load first spring flexes until making contact with the second then both springs flex together giving a softer ride, small bumps are handled by a single spring, larger bumps by both springs together. By clamping them you have taken the progression out making them stiffer. The clamped together stiffer pack now has less displacement per the same force applied with the spring not clamped which helps the pinion angle because the springs provide the opposing force when torque is applied to the rear end. If the goal is to control pinion angle you're better off clamping the springs together behind the axle, when torque is applied to the wheels for forward motion the pinion flange will tip up creating an opposing torque to the tires so the portion of the leafs in front of the axle compress together and the portion of the leafs behind the axle separate, by clamping the rear portion together you eliminate this separation when torque is applied. This is how the cal tracs work and why they are mounted to the rear, they also take it one step further by linking them back to the axle with a strut that loads in tension. So for controlling road input clamps in the front or rear doesn't make a difference but for pinion angle the rear is a better location, either location like 2 stroke said the trade off is going to be a stiffer ride.

your explanation sounds plausible! What I was trying to say is by placing a clamp in front of leaf springs, this causes the vibrations to be absorbed over more of the leafs. I used the word density, a more suitable word would have been more "volume+density". More metal volume or density for energy to be absorbed. This energy is either from the engine, driveline, road force which you feel as vibrations into the cabin. Pinion angle may be improved, but that is not the real problem, the transfer of energy is!

 

Thxs

Posted

Really? You are too my friend........Post#10596 from yours truly..........Darth Vader

 

Damn, CJ, hate to hear that! Look at it this way, I have spent over $2000 on parts to find out that it was bad wheels, talk about frustration! :banghead:

 

 

 

Now I have to buy new wheels! I was on autotrader Monday myself, but I am too stubborn to give up.

 

You my friend are always good for a laugh.

Yeah, but it's still the frame, right? Because I've fixed it, without doing anything to the frame.

 

So, yeah, it's definitely the frame.

Posted

I guess there is a lot of people who do not understand the meaning of frame beaming! It is a transfer of energy across a lintel of steel...in this case a trucks frame.

Nothing is wrong with the frame! It just transfers energy very well, which is then felt throughout the cabin.

  • Like 1

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