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Leaf Spring Overload Idea?

21K views 12 replies 8 participants last post by  Joelski2 
#1 ·
I'm still not 100% happy with my OME springs. They are decent but I can't seem to find a good balance of loaded ride and empty ride at the lift I want (1"-1.5"). Currently I sit on the overload a bit too much while empty due and this makes for a stiff ride. I've considered removing all overloads and doing progressive leafs in their place but then when I load it down (about 800lbs camping load) it will be bottomed.

While sitting in traffic yesterday a 2000-2005 era Superduty was stopped next to me and I saw they have a "top overload" spring (see photos). When looking under the truck once I got home it appears that we have room for such a thing with some custom brackets. I think this would work well as I would be able to change the overload rate and set in point easily and it would allow for a true two stage spring. I know air bags may seem like an answer but the cost and weakness of them steers me away. This is also much simpler with less to go wrong.

Any reasons why this would be a bad idea?





Thinking get a hold of a set of xterra springs (more arch) cut them down some to cut a stiffer rate and mount on top with all overloads removed.
 
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#2 ·
Sounds like you are looking for a set over helper springs


And not sure why you would assume airbags are "weak". I have had my bags for almost 10 years. Load a ton+. Driven and coated in sand, snow,ice, gravel, mud, salt. Crawl, high speed desert, air. Top out, bottom out. Three wheel hang in the air action. THey are still perfect. Even the super duty you have pictured has a set.

Back to your topic though. First off I assumed that the primary leaf pack would need to flatten out quite a bit before it would contact the upper overload leaf. THe upper overload would be part of the main leaf pack. From the dirt marking it doesn't appear that happens, rather the upper surface of the upper over load leaf contacts a bracket off the side of the frame. Since our leaves are positioned directly under the frame rather than to the side it might not works as well.

A traditional helper spring however seems more appropriate for our trucks. I have known a couple of trucks that have had these and have had good luck. Non wheelers though.
 
#5 ·
Sounds like you are looking for a set over helper springs

And not sure why you would assume airbags are "weak". I have had my bags for almost 10 years. Load a ton+. Driven and coated in sand, snow,ice, gravel, mud, salt. Crawl, high speed desert, air. Top out, bottom out. Three wheel hang in the air action. THey are still perfect. Even the super duty you have pictured has a set.

Back to your topic though. First off I assumed that the primary leaf pack would need to flatten out quite a bit before it would contact the upper overload leaf. THe upper overload would be part of the main leaf pack. From the dirt marking it doesn't appear that happens, rather the upper surface of the upper over load leaf contacts a bracket off the side of the frame. Since our leaves are positioned directly under the frame rather than to the side it might not works as well.

A traditional helper spring however seems more appropriate for our trucks. I have known a couple of trucks that have had these and have had good luck. Non wheelers though.
Helper springs do not fit the bill for me this time around as they are engaged 100% of the time and would actually make the unloaded ride worse. I ran a helper on my last truck and it did help with loads but also did some nasty things to the leaf pack and stiffened the ride a good bit.

The only part I don't like about air bags is the cost and potentially ripping them. I've dealt with air bags in the past and liked them but in flexing situations I'd be worried about them tearing. I think in the photo those are actually timbrens as that is where the bump stops are on Superdutys.

If you saw my leafs currently that are damn near flat at ride height (i want this). The best ride from leafs comes when the are just about flat. The issue with this, is that this means its also sitting on the current overloads (bad, makes it stiff). I don't think I would have issues making an upper overload contact and engage. I did notice that the leafs sit outside the frame on the SD, but I think it could still be made to work on ours. There is quite a bit of room between the frame and leaf pack.

Main goal I want to achieve with this is to have an excellent unloaded ride but then once it starts to squat with the weight, the upper overload would kick in and control the load.
You might say "Well that's what the current overload does..." and you would be correct. The issue is that at my desired lift height I sit on it constantly and it severely limits up travel. I want it gone so that up travel is more accessible and the unloaded ride is good.
 
#3 ·
As stated above, I think you are talking about helper springs. I've read some folks on here tried SuperSprings and had satisfactory results if that is, in fact, what you are going for. I've considered going to them too, but haven't made up my mind.
 
#4 ·
My last 7.3L F-250 had those top springs and they did a little bit i think but that truck was made to haul and tow pretty heavy loads. That being said I still put airbags on that truck to help the springs out and they worked well.

You probably could get something like that to work with the ome springs you have but it might take a bit of work finding what spring/length would actually work that could help with both ride quality and lift. I'd be surprised if you could get 1-1.5" of lift from just an extra AAL and still have to the truck ride decent. Although when you prove me wrong let me know and I'll copy you. Do you have the medium or heavy leaf springs?
 
#6 ·
Work I am ok with, spent a while figuring out the Tundra stuff so I'm not afraid to experiment.

Currently I'm running modified MDs. I have added different anti friction pads, leaf shims, and removed the large overload. This produces an acceptable ride at the height I want but , as stated, I'm sitting on the overloads a bit too much currently.

Before I go too crazy with this, I plan on adding back in the HD leaf and swapping the currently installed short overload for the long overload I removed. If that still does not provide what I'm looking for I'll go extreme mad scientist and give this mess a go.
 
#7 ·
Since we're throwing out ideas, would you have the long overload recurved before you swapped it back in? So it arches the opposite way as the main leafs. It seems that it would be a more gradual transition from non-overload to overload. But I f it's curved too much it could act as an anchor.

A note from personal experience. I was running TJM's HD leafs. The ride was too harsh both loaded and unloaded. At the suggestion of Greg at PRG, I cut the overloads to almost nothing. To act in their place I added air bags. This greatly improved the ride, and it was nice to have the adjustability. Unfortunately it seems like the regular leafs need the support of the overloads. The 3rd from the top leaf snapped about 6" forward of the U-bolt. It doesn't seem like you were heading in the 'no overload at all' direction. Just saying, you should have something there, weather it is an AAL, or an overload.
 
#8 ·
^Interesting. How short did you cut them? If you went all the way to the axle perch where it just acts like a block I could see that overstressing the other leafs.

After sleeping on it I may reconsider air bags as they really seem like the answer. I could then remove the overloads entirely and add back two progressive leafs to avoid murphy's issue.
 
#9 ·
As you can see, I cut a considerable amount. I left enough to mount the air bag U-bolts on the bottom overload, and enough to span the axle's U-bolt on the second one.

This is from when I swapped them out for Alcans. I wish I swapped one or the other in this picture. One is forward and one is backward.
o
 
#10 ·
I have Hellwig helper springs. I think they are #1908 but I'm not sure because Hellwig still does not show them on their website. They were installed about 5-6 years ago. I was the lucky "we need photos for the brochure" guinea pig.

Here are some pics of the springs and what they can do. 1st pic is unloaded no tongue weight. 2nd full tongue weight NO WD. 3rd full tongue with WD

The trailer tongue weight is 450-540lbs. (yes I'm pushing it a little but the 4.56 gears help :)
 

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#11 · (Edited)
So I can wrap my head around this idea, it looks like the F350 setup has a pad up on the frame that the overload spring contacts once the truck sags enough? Does this mean you are relying on the truck to sag enough to make contact with the upper mount? Wouldn't this also limit wheel travel if the stops were placed too low?

Would you make the upper frame stops adjustable? This would be the only way I see this working properly for something you take off road. Maybe do something like the pin on jack stands? Bed is empty, they are adjusted up, when you know you are going to load up, you pull the pin, drop the stop down closer to the springs and pop the pin back in?

Not to beat a dead horse, but my plan for my rear suspension is going to be springs setup for unloaded and airbags for when I am loaded. I just don't think a person can have the best of both ride and cargo carrying with a static suspension.
 
#12 ·
That is pretty much exactly how I had planned to tackle this. Although the more I think about it, air bags keep looking better and better. I can buy a la cart bags for about $40 each to play with so I may do that. I've also been thinking about how you could pretty easily rig up an auto level function with air bags and OBA. OBA was in the plans already so air bags seem like they could go hand and hand.
 
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