Dad has an '07 4X4 Lariat loaded and my brother has a bare bones 2WD XLT. both 5.4's The 4WD has three leafs in the spring pack which I thought was standard/normal on the new trucks. But then today I saw my brothers truck for the first time and it had four leafs in the pack. I don't know what he got on the truck, but I'm pretty sure he didn't get any type of heavy duty payload option or anything. Looked like the second leaf from the top was the 'additional' one on his truck. Just curious what the difference may be and why it came that way???

 

The number of leafs in a spring is determined by spring rate. Each spring will have main leafs plus a 2nd stage rate leaf. The truck with the 3 leafs is a lighter rated spring. the springs are selected by payload and wheelbase. Is the bare bones 4x2 a supercab 8' bed. If so it will have the 7700lb payload by default.
In any case, don't be alarmed, I am sure that both trucks are spec'd out OK.
Check the stickers or stop by the dealer to verify the payload package.

 

No. My brothers 2WD is a standard crew cab, 5 1/2' bed.

 

They changed the leaf pack sometime because my 04 has 4 leafs and my buddys 06 has 3 with the same truck option for opition

 

Galaxy,

I meant to look up your part numbers for each vehicle at work but got distracted. Do you know the part numbers? They should be stamped on one of the main leafs. like 7L34-5560-xx I can check to see what they are rated at.

Like extremeethan said, sometimes there are running changes that affect what gets released in the plant. I haven't worked on the P221 (04-08) F150 for over a year now but that was my suspension design.

Are both trucks 07 Super Crews?

Hope to hear back from ya. in the mean time no worries. both trucks should be fine.

 

in the 97-03 body style the crew cabs got an extra leaf because of the weight difference.

My bet is the 2wd has softer springs (softer ride on a 2wd) but with 4 of them it still have the payload of the tuffer riding 4wd.

 

Don't get too carried away with the amount of leaves because the 3 leaf and 4 leaf will have the same capacity due to thickness of steel (.380 for 3 leaf and .323 for the 4 leaf). The typical 3 and 4 leaf will both have around 1500 lbs capacity per side and this is what the spring itself can handle. There's also some 1700 and 1900 lb options out there as well. Spring rate isn't really a concern for full size trucks unless you're offroading with them and the 4 leaf with thinner steel will actually have a lower spring rate than the 3 leaf which would make the 4 leaf more beneficial to the offroader. However, the spring rate really becomes irrelevant on pickups because once the overload is engaged the rate skyrockets because it's pretty hard to bend a piece of steel .662" thick. So whenever you're looking at trucks for hauling or towing pay attention to the spring capacity and not the rate.