Super Duty -rear spring conversion.
iv read this a couple times;
rear SD springs bolt right in place of the stock springs, all you have to do is drill out the front hanger for the larger spring bolt

the question is,
the purpose for this conversion is "mainly" done to improve the ride quality.being longer springs,is what improves it.
so if the springs are longer,i don't understand how the perches are supposed to line up?
by the sounds of the line above,it's like the springs are the same length,and just require larger (reamed out) holes for larger bolts or something.

now,am i crazy or,when i go to measure--leaving the rear perch is the same location-- i see the SD spring perch will need entire new holes further up.in fact,it looks like i'll need to re rout the e-brake cables just a little.

what am i missing here?

these come off an 03 or an 04 SD im pretty sure.i'll post pics before i start getting my old perches off,dont worry.

iv decided on keeping 6 of the mains.i figure being longer,thus a better ride,will be worth keeping the 6 long ones.
i'll need a new center bolt and U-bolts.

the running around for parts for my fuel tank,and fabricating a bit took me all day lol.so i didn't get a start on this.
i did stop in and grab my other BUDD rim tho!
when i run after my new centers and U's i'll grab a 45 for my exhaust.im gunna tilt that 90 i have at a 45 and use the other 45 to get me out.this keeps me low enough to clear the frame.cut a short 3.5 section,toss in a hanger,and then shoot another exhaust clip for fun. peace and quite in the cab again here we come.....thank the maker! lol.

oh the tank;
replaced my 23 gallon poly (front) for another just like it.
filled her up,and checking my mileage now.50 miles so far,and not yet down to F mark.
more than a couple gallons at a time and no more diesel trail........im moving on up.

 

here we go.i couldn't see anything lol.dark.so i just aimed and shot.
got 'em good tho.

 

oh man.i shoulda snapped a pic or two of my overload 4 pack.
that SD overload i wanna toss on top of them to make it a nice 5 pack.
see,the reason im not going with so many mains like in these pic,is cus it would ride like a buckboard.no thanks lol.
(i scored these free when i got my dump bed! he cut the frame off,and i took the whole works home.)
i grabbed 4 pics of those,so i may as well post the last one;

 

I put F450 springs under my 79 F350 (wrecker) and all I had to do was drill out the hangers. The bolts are quite a bit bigger and metric too.
The bolt you are calling a center bolt, is called a tie bolt.

 

yeah,that's what i figured needed to be done here.how else ya gunna put longer leafs on right lol.if they bolted in the same location,they wouldn't be longer and give a better ride.
the wording was odd and making me over think things.....i think lol.

oh man.i kinda wish i didn't fill the new tank now.last thing i wanna do is drill into it lmao.
i shoulda done this in a different order.

 

I didn't move the hanger, I just drilled it out. I didn't measure it but it lifted it enough the driveshaft is barely long enough and the shocks weren,t long enough. And as far as ride quality I wouldn't say it improved, but it will sure hold a load. lol

 

For the shocks, you may have to use ones meant for a 4x4 F350, being that they sit 2" higher than your F250 and so the shocks will be longer. Those are the shocks I'm using in my truck even tho it's 2wd, cause of the thicker main packs and the 1" blocks under them.

 

why would it bring me up LCAM?
2" rear lift is out of the question.id have to stay stock springs.im not trying to sit this whole 10 main in.just 6 of them.
im not going to sit them on a 4" block.just the same 2".
does anyone have a write up on this conversion? things aren't adding up here at all.

remeasuring the lengths today,i do see they are close to the same.
being so,im not sure what makes it worth swapping them.i do like the tuffer looking spring hangers over stock.but im not understanding ride quality improvement.
im tempted to just go and have my overload spring pack put together and get new U-bolts and be done with this lol.
but im not gunna pass on a good opportunity for an upgrade.
i'll wait for more info before i get the torch out.

 

I really doubt there is ANY ride improvement at all. F450's bounce off the cracks in the pavement to begin with, putting them under a lighter chassis will only make them more surly. Only my long wheelbase carrier will have any ride comfort when it is loaded down past 15k GVW.

 

not F-Superduty (F-450 equivalent) but Super Duty as in 99-04 F250/350 leaf springs guys.

not having any luck with my exhaust either today lol.been a worthless day here.

least its been nice driving around for parts with a truck that doesn't leak fuel anymore.

heres a little info on what im trying to do:
https://www.ford-trucks.com/forums/8...rovements.html

working on the REAR.
latter id like to do the front too,only if i can find a way to keep stock height..but nothing of concern to me right now.

 

I am confused by your post.

The pics you showed are from a F-superduty or a F450/F550(99-07) CAST HANGERS!! are a dead give away

They will NOT ride better than your current springs, Is your truck a cab-n-chassis? If so your springs are only 2.5" wide

If you use Superduty springs(99-07 F250/F350) they will ride better than OBS(old Body style) springs. The B codes ride the best

 

oh ok.the springs i have are not what im after.no wonder things weren't adding up.
nope mines a pickup w/3" springs.
thanks Brad!
this is why i didn't get the torch out first.

 

Oh, I too thought you're talking about F-Superduty springs which as Towcat said ride like a dump truck and will jack the *** end up if you don't lose the blocks to compensate for the extra leafs and thickness.

About the '99-up SuperDuty springs, I dunno, I do have some leafs off one of them trucks inserted in my factory leaf packs, but I cut them down to size and have no idea how they would work in place of the factory springs...