I had my leaf springs on my '54 F-100 re-arched and now the frame rails sit 23 1/2" from the ground (stock is 17"). Even had to replace the shocks. I cannot park in the garage as roof hits door header. I thought I could lose about 5" if I moved the axle to the top of the springs. My concern (if there is one) is sprung verus unsprung weight and what effect it would have on the vehicle. Anyone have any knowledge on this? Would it be better (safer?) to have them de-arched and/or reversed eyed to lose approx. 5"? Also, where can I get plain 5 on 5 1/2 wheels? Appreciate your help.

 

The only safety issue is that in a spring under configuration the u-bolts have to support the weight of the truck. Not a big deal since there are plenty of factory applications built like that, just make sure that you use decent bolts.

It's not going to change sprung vs unsprung weight, just the COG.

As far as plain steel wheels. try American Racing. 5 on 5.5 is a very common pattern, early jeeps, scouts, early broncos, and most 1/2 ton ford pickups.

 

Gramps -
Sprung vs. unsprung weight doesn't change with axle location. It will change with the weight of the wheels and tires you choose (the unsprung weight).
Moving the axle to the top of the spring should give you more than the 5" you are looking for though, assuming you have a 7 or 9 leaf spring. Will you then need to raise it some to level the truck out? You could be chasing this problem for a while.
Have you driven this setup for a few miles to determine the ride quality? You may want to drop some leaves later to improve the ride or lower the truck. If that's a possibility, I would do that before addressing the axle location.
My preference is to re-arch the springs here. Moving the axle will involve moving the spring rests to the other side of the axle and rewelding them to the housing. I just prefer the idea of the truck weight sitting on top of the spring vs being supported only by bolt tension.
Think of it this way: In the stock setup (spring on top), every time you hit a bump, the spring deflects to absorb it and the bolts just keep everything connected. Ther is little load on the bolts.
With the axle on top, every bump you hit is trying to stretch the U-bolts. Even grade 8 bolts will fatigue given time and vibration. Rusty old bolts fatigue faster.
My bet is that the Ford engineers gave this axle position some serious thought before putting the spring over the axle. I wouldn't second guess those guys since I'm still driving it that way 50+ years later.

 

Thanks for the quick replies. I now have ten (10) leafs in the rear and surely could remove at least two, perhaps three. I appreciate your thoughts on safety so I will not be flipping the axle. If I take the springs off to the shop how can I make sure the re-arching will be enough (and even). Currently cannot drive the '54 on the street. Any thoughts on using lowing shackles? for an additional 1 or 2 inch drop?

 

Lowering shackles will only give you 1" of ride height difference per 2" of shackle change, and they effect the pinion angle.

 

Any thoughts on how to determine how to check (at the shop) that the springs are correctly de-arched the right amount when they are not on the truck??

 

Gramps -
Measure the arc height you have now while the springs are on the truck and loaded with the truck weight. Measure them again in free state - off the truck. That exercize will tell you how much the spring deflects to support the truck weight.
Tell the shop how much you want to lower the truck and give them the dimensions. They should be able to give you exactly what you are looking for.
Temper and spring strength are the same - its just the arc shape that changes.
BTW - are you going to have teflon/nylon buttons or wafers installed between leafs? I run monos, but understand that is a good idea to eliminate the squeking that my old leafs had.
Good luck.

 

Thanks Randy Jack & OldJeep. I have the knowledge I need to do the job proper. This is a great forum - quality answers.

 

Why not take every other leaf out for a total of 5 (thats what I have, my 2003 F150 s/c has 3 from the factory) before you do anything else. Flipping the axle will have no ill effect, just use new hardware.

One other thought if you flip the axle you will have to "c" notch the frame for travel clearence

Chuck

 

Hi Merc546 - If I did what you suggested would I still have to de-arch and/or reverse the eyes to lose approx. 5 inches? What do you think I would lose by just removing 5 of the 10 leafs??
I most definitely need to lose a minimum of 3 1/2" to clear the garage door header. 5" may not be necessary - just don't want to do the job twice.

 

Not sure how much height you will lose but the ride will be much smoother. I know Mid Fiftys suggest removing every other one, keeping the short one at the bottom then removing the next and so on.

By removing these leaves after a short period the springs will begin to relax some, so along with the height of the leaves and the spring relaxing perhaps you will get it back down to the desired height. Also you could replace the rear hanger with a extended hanger they claim it will drop the rear 2 inches.

Chuck

 

On my 49 F1 pu I did what No Limit engineering suggested and that was to remove every other spring, I remove 4 of 10 and placed No Limits teflon liners between each spring. The ride is very much like a car and not a truck but this is not for hauling it will handle what you would normally put in a cars trunk and a little more. I happen to like the ride quality.

 

Sounds like I should be able to do the work in my driveway - C-clamp the unit and remove four or five leafs and use extended hangers at the rear and button it back up (with new grade 8 hardware of course). My thanks to everyone.