Question for F350 4x4 owners

DragRag

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How can this be if most people are saying that their springs end up flat with the weight on them. They must have started out something higher than flat with out being compressed by the weight.

They all started life just about flat, I have never seen a positive arched spring from the factory. Most are reverse arc, with only some being flat these days. That is unless it has been re arched, or an add-a-leaf installed.
 

12clip

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I guess I should not have said "started out". I'm not talking in terms of sag here.

I'm just saying a spring that is straight and flat while compressed under load and then returns to a positive arc when the truck is lifted on the hoist, to me that is a positive arc spring.

It certainly is not a negative arc spring and it has to be one or the other.
 

Diesel_brad

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I guess I should not have said "started out". I'm not talking in terms of sag here.

I'm just saying a spring that is straight and flat while compressed under load and then returns to a positive arc when the truck is lifted on the hoist, to me that is a positive arc spring.

It certainly is not a negative arc spring and it has to be one or the other.

With the axle HANGING from the spring a F250 TTB negative arch spring will become a positive arch spring.

Cant judge a spring as positive or negative unless to full amount of the trucks weight is sitting on it
 

Goofyexponent

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I must agree with the majority here. When I did my D60 swap in my 1993 F250 (with BigRigTech's help of course) I gained about 2.5 - 3" lift in the front. The truck sits a little nose high right now because I left the Factory 2" F250 blocks in the rear. I fully intend on installing the 4" F250 blocks as soon as I get off my @$$ and get new U bolts made up.

However with that being said, the front springs in my truck came from a 1992 F350 7.3 auto Crew Long box SRW, and went under my 1993 F250 supercab LB 7.3 auto....and they are flat or nearly flat with the weight on them. You will have to have them re-arched (which don't really last all tha tlong) or get new springs made or buy a kit to get height. Keep in mind that you will need a drop pitman arm and drop track bar bracket if you go too extreme.....you will get BAD bump steer if you don't!!!
 
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