Rear Leaf Spring Helpers Lifted My truck

[JOEZ33]

I've had a worsening problem of my 4 door 98 sagging in the rear, especially when its full of fuel, and forget it if I dare to put something in the back of the truck while it's got fuel. I couldn't afford the new springs yet, so instead I figured what the heck and installed some leaf spring helpers $41. I got them at NAPA, and unfortunately they were made in china, the instructions were rediculous and completely useless, and I don't really know if I installed them properly at all. On this truck the very bottom leaf is straight, not curved like the ones in the "instructions". If I install the leaf helper spring all the way at the base, completely underneath the existing straight leaf spring, the rear end actually sags worse but gets stiffer. So I installed it in between the straight bottom leaf spring and the rest of the stack. The rear of the truck came up over an inch, and the ride quality is absolutely perfect, not stiff at all, and now there's much less "shudder" in the suspension when going over bumps.

Before installing them the front end was higher than the rear with a full fuel tank. Now with the same full fuel tank the rear is higher than the front by over an inch. I had to raise the front end back up to level it out, as the fuel tank drops toward empty I'll have to see how it all levels out and make some final adjustments. The truck looks better now, a little more wheel clearance always looks nice to me.

If anyone has any suggestions on properly installing them I'd greatly appreciate it. I tried about 5 different ways of installing them and settled on the way they're in now.

JOE

 

[gavin]

sounds like you did it correctly. Sounds like you just got an add-a-leaf. Add-a-leafs are supposed to be installed between the leaves that are just shorter and longer than the AAL.
When I installed mine, I believe it was 1 leaf up or so.
The flat leaf you're talking about is called an "over-load" leaf. Of course nothing can be installed under this, as it's there for if the back is REALLY loaded and flattens the whole leaf pack.

So you have the AAL at the bottom of the pack, and the leaf just above it is longer than it, not shorter, correct?

I hope I made sense

 

[steventadams]

sounds like you did it correctly. Sounds like you just got an add-a-leaf. Add-a-leafs are supposed to be installed between the leaves that are just shorter and longer than the AAL.
When I installed mine, I believe it was 1 leaf up or so.
The flat leaf you're talking about is called an "over-load" leaf. Of course nothing can be installed under this, as it's there for if the back is REALLY loaded and flattens the whole leaf pack.

So you have the AAL at the bottom of the pack, and the leaf just above it is longer than it, not shorter, correct?

I hope I made sense

Do you mean like a pyramid sort of lay-out?

Original Leaf Pack

------------
-----------------------
---------------------------
--------------------------------

W/ AAL

------------
------------------ <-- AAL
-----------------------
---------------------------
--------------------------------

 

[gavin]

exactly

and if your AALs are like mine, there is a short-side and a long-side. Honestly I don't know which side goes at which end... or if it matters. As long as they are the same on both leaf packs.

 

[JOEZ33]

Actually this is a bolt on leaf that is straight most of the way, and then at the very end it makes a 45 degree bend which is where the U bolt slides in place. The other end has two little plates and one bolt that slides through them, it also has a piece of plastic nylon riveted to it. Both ends just clamp underneath the existing leaf spring, but are not sandwiched at all. The trick is to install it while the truck is jacked in the air from the frame, where the axle is hanging down at full extension. Then after bolting the leaf helper in place, you lower the weight of the truck back on the ground. Now that the leaf helper is adding weight capacity, the truck sits higher until I add a lot more weight. I found a picture from jc whitney of an identical one, and it's installed the way the I purposely did not install it, because it actually lowered the truck as a result.

 

[gavin]

ahhhh okay.
basically just like the Hellwig Helper Springs.
In that case, I would expect the helper spring to be at the bottom of the pack, but above the flat over-load leaf.

well... except that the picture shows it installed underneath the overload leaf....

edit: that picture is for an SOA leaf setup. The head of the centering bolt is on the bottom of the pack, not top

the hellwig helpers I've seen, and it's a half'er like you got, mounts on top of the leaf pack.

 

[glfredrick]

I've been running the full-length under the spring models for years on my stuff. I totally remove the factory fat helper spring. It doesn't help -- it just stops everything when it gets that far.

I get nice flex without the fat bottom leaf.

 

[louietran]

JOEZ33,

Since you have installed the helpers between the flat bottom (over load leaf) and the stack, have you had any issues or problems? I thought of installing it that way too and not how they recommended. Also, did you install it in front or behind the axle?

 

[gavin]

JOEZ33,

Since you have installed the helpers between the flat bottom (over load leaf) and the stack, have you had any issues or problems? I thought of installing it that way too and not how they recommended. Also, did you install it in front or behind the axle?

there is no helper spring you want to install under the flat overload leaf (or above it, if it's SOA).

you're supposed to install any kind of add-a-leaf or helper spring between the overload and next leaf in the pack.

the helper leaf will make it WAY too stiff, since the overload leaf doesn't do any work unless the suspension is fully compressed.


edit: okay I just looked at the first pic again.. and they do show it installed under the overload. But with the way that helper leaf is designed, it should work either way.

 

[louietran]

Does it matter if you install it in front or behind the axle? It doesn't say in the instructions and obviously installing it under the over load leaf doesn't work well as they illustrated.

 

[JOEZ33]

JOEZ33,

Since you have installed the helpers between the flat bottom (over load leaf) and the stack, have you had any issues or problems? I thought of installing it that way too and not how they recommended. Also, did you install it in front or behind the axle?

UPDATE: those spring helpers have been on there for a few months, and I got sick of them and removed them the other day. When I first installed them it was full of fuel, it rode nice, and we loaded up the camper to drive 600 miles. After the whole trip I was now dealing with normal daily driving, which is usually about 1/4 to 1/2 tank of fuel and zero load in the back of the truck. With the truck light, and empty, it rode like crap. That's right, CRAP. Partially because I had to crank the front end torsion bars a lot to make the front height level with the rear, so the whole truck was really bouncy. Going over speed bumps or dips in the road wasn't nice either- you have to brace yourself because you know that "after" the bump when the truck rebounds it's going to hurt.

I removed them, lowered the front end to level it all out, and now the truck has that factory lazy ride again. I like it better than being bounced out of my seat.

Overall my point is that the springs have one function, which they did technically do, which is to stiffen up the rear springs. Just remember that when your not actually carrying any heavy objects that the ride will suffer.

 

[gavin]

yes, that's why they're called helper springs.
they were designed to be used when towing or hauling, to help prevent spring sag and fatigue

 

[JOEZ33]

yes, that's why they're called helper springs.
they were designed to be used when towing or hauling, to help prevent spring sag and fatigue

well they "helped" buy only under heavy load, which makes perfect sense. When not under load they're so stiff and preloaded in one direction only that the shocks just don't properly match them. I think if I had a matching set of shocks that were designed to help prevent rebound after going over bumps it would have rode nicer, but not worth all the effort. I think the best solution is to replace the springs with new, and possibly add a leaf. Adding a leaf doesn't preload all the force in one direction like my situation did. Of course the way I installed those helpers is obviously what caused it to push upward so much, it in fact lifted the truck over an inch.