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- Joined
- Jan 13, 2014
- Messages
- 335
- Reaction score
- 12
- Points
- 18
- Vehicle Year
- 2002
- Make / Model
- Ford
- Engine Size
- 5.0
- Transmission
- Automatic
I think I'm looking for some new front springs.
OEM springs have always been brutally harsh, even with the added weight of the Expo 5.0 and 4R70W transmission vs the 3.0 and 4R55E
Poking around, seems like there are 3 different OEM springs but if I'm reading the specs right, all have the same spring rates and compressed height, just different free lengths to compensate for the engine/trans/chassis combinations. One thing I can't find on the specs is number of active coils (yea, an important number for sure!)
All springs have .76" wire, 3.99" ID/5.5" OD, a 12.5" compressed height and 567 lbs/in rate.
Free lengths are 16.14", 15.92" and 15.53"
I'd hoped that a set of I4 springs would maybe be an answer, perhaps lower the front end of the truck and soften the ride at the same time but if the wire size/spring rates are the same, I suspect I'd get the nose to drop, but not ease up on the harshness.
So, one option is a set of custom springs but I'd all but be shooting blind on the specs. I'd need numbers I simply don't have.
Can I take the weight on each front tire, factor in the leverage from the length of the lower control arm to calculate the actual compressed load on the spring?
Seems to me if I know the actual load on the spring, the desired compressed height with that load and a "guess" on say a 5% reduced compression rate, I should be able to contract out a set of springs with a wire size/# of coils that would fit my wishes.
Crazy? Sane? Or is there a better off the shelf option?
Cheap, easy answer is to try the I4 springs and for the $60 and an afternoon, not a bad test but I have low hopes for any ride improvement.
OEM springs have always been brutally harsh, even with the added weight of the Expo 5.0 and 4R70W transmission vs the 3.0 and 4R55E
Poking around, seems like there are 3 different OEM springs but if I'm reading the specs right, all have the same spring rates and compressed height, just different free lengths to compensate for the engine/trans/chassis combinations. One thing I can't find on the specs is number of active coils (yea, an important number for sure!)
All springs have .76" wire, 3.99" ID/5.5" OD, a 12.5" compressed height and 567 lbs/in rate.
Free lengths are 16.14", 15.92" and 15.53"
I'd hoped that a set of I4 springs would maybe be an answer, perhaps lower the front end of the truck and soften the ride at the same time but if the wire size/spring rates are the same, I suspect I'd get the nose to drop, but not ease up on the harshness.
So, one option is a set of custom springs but I'd all but be shooting blind on the specs. I'd need numbers I simply don't have.
Can I take the weight on each front tire, factor in the leverage from the length of the lower control arm to calculate the actual compressed load on the spring?
Seems to me if I know the actual load on the spring, the desired compressed height with that load and a "guess" on say a 5% reduced compression rate, I should be able to contract out a set of springs with a wire size/# of coils that would fit my wishes.
Crazy? Sane? Or is there a better off the shelf option?
Cheap, easy answer is to try the I4 springs and for the $60 and an afternoon, not a bad test but I have low hopes for any ride improvement.
