Re-arching my own leafs. Not what I expected.

[ponkotsu]

So I finally started this project. Wasn't so hard to pull the leafs out, as it wasn't so rusty. My Mountaineer is sitting about 1.5 - 2.5" low. There is no published spec, so it's just an estimate based on visual and stock photos.

I expected the leafs would be flattened out. But I measured them, and they measured to exactly the dimensions of a stock spring. (6.5" arch). This is really odd. The vehicle is definetely riding low. The shackles were fully extended to the rear, almost bottoming out. I'm not a spring expert, but from what I've researched, this is an odd situation. Normally the springs will be visibly flattened out with age.

So I figure as long as I have them out, I'll continue with my plan. I re-arched them with a press. I put an additional 2.5" of height in them as planned. That brings them to a 9" arch. Getting them into the truck looks like it's going to be a challenge though!

Anyone seen this before? Almost seems like they are defective or wrong springs. Maybe the leaf is too thin. (Has correct arch but too low spring rate).

 

[corkey]

i bet they are the right springs,, when i took mine out they did the same thing,, it's not the arch that goes away, it's the strength of the arch,, they get weak, and need to be re tempered,, i don't think that can be done at home,,

 

[koda2000]

yeah, i had a feeling this wasn't gonna work. i don't know anything about metallurgy, but some sort of heat treating is critical to providing the "spring" in a spring. i guess they just fatigue over time.

 

[deweyville65]

So I finally started this project. Wasn't so hard to pull the leafs out, as it wasn't so rusty. My Mountaineer is sitting about 1.5 - 2.5" low. There is no published spec, so it's just an estimate based on visual and stock photos.

I expected the leafs would be flattened out. But I measured them, and they measured to exactly the dimensions of a stock spring. (6.5" arch). This is really odd. The vehicle is definetely riding low. The shackles were fully extended to the rear, almost bottoming out. I'm not a spring expert, but from what I've researched, this is an odd situation. Normally the springs will be visibly flattened out with age.

So I figure as long as I have them out, I'll continue with my plan. I re-arched them with a press. I put an additional 2.5" of height in them as planned. That brings them to a 9" arch. Getting them into the truck looks like it's going to be a challenge though!

Anyone seen this before? Almost seems like they are defective or wrong springs. Maybe the leaf is too thin. (Has correct arch but too low spring rate).

This is something better left to the professionals. You may be able to bend the springs to a point. I seriously doubt they will hold up for long without being heat treated. They will probably break. Remember, springs are not just cold rolled steel.

 

[ponkotsu]

yeah, i had a feeling this wasn't gonna work. i don't know anything about metallurgy, but some sort of heat treating is critical to providing the "spring" in a spring. i guess they just fatigue over time.

Not so fast! Put it back together and did a good test ride. Got exactly the ride height I targeted, and much smoother since it's not resting on the overload springs. And as a side benefit, my highway vibration is greatly reduced. (Guess that confirms the diagnosis of u-joint because the angle is more correct now).

Not sure how long it will last. But if it buys me a year or two, mission accomplished. I have more time than money now, and I get a kick out of learning new things. I'll keep an eye on the ride height and post updates here if it changes.

 

[ponkotsu]

This is something better left to the professionals. You may be able to bend the springs to a point. I seriously doubt they will hold up for long without being heat treated. They will probably break. Remember, springs are not just cold rolled steel.

We shall see. Like I said in an earlier post, I'm also very skeptical. But if you do some research on the web, you will see this is a very common practice. Even the local spring shop does it this way. One could argue that they will last longer than OEM, since they are already "broken in".

 

[koda2000]

We shall see. Like I said in an earlier post, I'm also very skeptical. But if you do some research on the web, you will see this is a very common practice. Even the local spring shop does it this way. One could argue that they will last longer than OEM, since they are already "broken in".

well, let us know how they hold up (no pun intended).