[reptillikus]

I know BigNorm did a few years back, but he hasnt posted here in a few years either. The offset center pin set the axle way forwards, and he had to runt he shackle in front in order to keep the amount of lift down.
Id swear there was another, but i cant remember who it was anymore :brownbag


Remember that some F150s have 2.5" wide springs (i believe 2wd only but i could be wrong).

 

[Dan Theman]

I know BigNorm did a few years back, but he hasnt posted here in a few years either. The offset center pin set the axle way forwards, and he had to runt he shackle in front in order to keep the amount of lift down.
Id swear there was another, but i cant remember who it was anymore :brownbag


Remember that some F150s have 2.5" wide springs (i believe 2wd only but i could be wrong).

I thought those were chevy leafs, because of the overload. I guess the extra length would explain why he had to extend the front. Maybe the offset center pin would help move the tires away from the firewall. I definately don't want to run my shackle in the back. My rear springs don't have what I would call an overload. I know that some were 2.5".

 

[fordguy_78]

bearfoot_25 ran his bronco springs upfrunt Show sas thread and Flex pics

 

[Dan Theman]

bearfoot_25 ran his bronco springs upfrunt Show sas thread and Flex pics

I just came across that. Thanks. I think that's the route I'm gonna go.

 

[SpareParts]

I did a SAS swap with a 94' D60 on my 4 dr dually, it was originally a 2wd truck and I converted it to a 4wd with parts from a 92' F-250, springs and front spring rear hanger. I also did a shackle reversal with the rear leaf spring shackle and the 79' front spring mount. I moved the rear frame mount forward as in many of the posts but the ride is pretty harsh and is bouncy.

I have tried different shocks, originally I had the yellow Monroe's and I thought they were the problem. I switched to the Monroe Sensetracs and the ride improved but the bouncing got worse. My thoughts are the shackle is laid down too far and all the movement in the shackle is tranfering into making the truck move up and down.

Is this common on this set up?

Thanks,

David

 

[Dan Theman]

I did a SAS swap with a 94' D60 on my 4 dr dually, it was originally a 2wd truck and I converted it to a 4wd with parts from a 92' F-250, springs and front spring rear hanger. I also did a shackle reversal with the rear leaf spring shackle and the 79' front spring mount. I moved the rear frame mount forward as in many of the posts but the ride is pretty harsh and is bouncy.

I have tried different shocks, originally I had the yellow Monroe's and I thought they were the problem. I switched to the Monroe Sensetracs and the ride improved but the bouncing got worse. My thoughts are the shackle is laid down too far and all the movement in the shackle is tranfering into making the truck move up and down.

Is this common on this set up?

Thanks,

David

pic of mount/ shackle in question?

 

[SpareParts]

Here's a pic of the truck, I don't have a close up one of just the shackle. Sorry about the big pic.

 

[AUBronco]

From the pic doesn't look like you have enough angle on those shackles. They should be laid back at a 45* angle.

 

[SpareParts]

They should be laid back more? All the Chebbys and Dodges I have seen have them almost straight up and down or at 90 deg. from the leafs. What is the thought on laying them down so much? I would like to make the leafs flatter, or the front down to give me less caster but I don't want to lift the truck to the sky either.


David

 

[AUBronco]

Look at these pics:

And

 

[fordguy_78]

yeah the shakle needs to be at about a 45degree angle and personly i would scap thoes f250 springs and get some f350 ones

 

[SpareParts]

I was wondering it that was part of my problem, F250 springs that is. They do have a negative arch, and maybe part of my problem.

When you guys hit a bump, does the front end almost bob up and down. It looks like to me when the spring compresses it would move the shackle in an up and down motion. Which in turn would cause the body to move with it, maybe it is the soft F-250 springs?

I will try to get some better pics tonight.

 

[reptillikus]

First thing id do is ditch the F250 springs, they are negative arch, and alot stiffer than the F350 springs. Then if the ride isnt acceptable you can mess with the shackle angle, altho i think the problem lies in the springs. The shackle angle on my SASed F250 isnt all that great, but it still rides a lot better than a stock F350.

 

[Andy351]

your shackle angle is fine. the f250 springs are your problem, they are about double the spring rate of an f350 leaf because they are for IFS/TTB.

 

[SpareParts]

your shackle angle is fine. the f250 springs are your problem, they are about double the spring rate of an f350 leaf because they are for IFS/TTB.

The yard I deal with said there was only 2 spring rates, I don't remember what they were. I think he was talking about both 250 and 350's in the OBS trucks. I get along with them very well, I think thats what Hollander was telling him. So in that case I actually need the light weight and was assuming the heavier one was from the F-350.

I do know mine that I currently have on there is from a F-250.

 

[Andy351]

f250 springs are wrong, period. an IFS/TTB design needs a MUCH higher spring rate than a solid axle, even if the solid axle is in a truck rated for more weight. it doesn't have anything to do with the arch really. their information sounds a little misguided. f250s had 2 weight ratings (D44HD vs D50), i don't know how many f350s had. then throw in the different motor combos (SB vs BB vs diesel) and i think theres probably more than 2 spring ratings.

 

[reptillikus]

Yep, there are diesel & gas spring rates for the 250 & the 350, so thats atleast 4 different packs right there. Trust me, get the F350 pack, i did that for my F250, and it made a big difference.

 

[SpareParts]

I'll try to talk to them today, I know they have a 4wd 4 door F-350 there. I'll see if I can't get them, I do know it has a deisel in it instead of the 460 like mine.


I looked at them they are 1 1/4" thick leafs and the F-250 sitting next to it was 1 1/2". I haven't had a chance to measure mine yet, I'm betting they are the 1 1/2".

 

[Redneck Rigger]

Sorry to cut in, but if I was to box in the crumple zone, fab up a crossmember, use a front hanger from (lets say a 78' 250?), use the rear hanger (off the front springs) of an 80's leaf-sprung 250 or 350, and steering off a late 80's/ early-mid 90's 350 steering in order to do a leaf-sprung sas swap, correct?

If I follow correctly, I would need to narrow my front spring mount into my fabbed-up crossmember for 32" spacing, but I could mount them in line with the framerails (wih an x-member of course) for a 36" spacing? And most of yall get about 4"-5" of lift with factroy f350 springs, right?

It's time to put new balljoints and bushings on the ttb, and before I cuss and fight, and pour money into it (and still having to deal with all the allmighty tire-eater:whiteflag), I'm going to at the very least least consider a low-buck solid 44 swap, even if i do end up spending a few extra $.

Thanks!

 

[Shadofax]

Sorry to cut in, but if I was to box in the crumple zone, fab up a crossmember, use a front hanger from (lets say a 78' 250?), use the rear hanger (off the front springs) of an 80's leaf-sprung 250 or 350, and steering off a late 80's/ early-mid 90's 350 steering in order to do a leaf-sprung sas swap, correct?

If I follow correctly, I would need to narrow my front spring mount into my fabbed-up crossmember for 32" spacing, but I could mount them in line with the framerails (wih an x-member of course) for a 36" spacing? And most of yall get about 4"-5" of lift with factroy f350 springs, right?

It's time to put new balljoints and bushings on the ttb, and before I cuss and fight, and pour money into it (and still having to deal with all the allmighty tire-eater:whiteflag), I'm going to at the very least least consider a low-buck solid 44 swap, even if i do end up spending a few extra $.

Thanks!

just a comment on your thought of using a D44...unless you get a HD one, you'll need a 76-77 1/2Ton axle and be able to weld on your own leaf perchecs and cut off the factory wedges for coil/radius arm. If you go with a HD axle, it may already have knuckle out 8 lug stuff. Just trying to make sure you thought all that through.