I went ahead and bought some offset ball joint sleeves hoping that perhaps they would be sufficient for 2.5 lift springs. The units I received are Specialty Products Company 23268/9.
23268 caster +2.3, camber+0.5, Driver side
23269 caster +2.6, camber+ 0.3, Passenger side
according to their site:
These sleeves have a fixed positive camber and caster change and are designed specifically to align trucks that have been lifted or to provide more caster change than our standard 23220 Series sleeves. For maximum drivability and to compensate for road crown, use a 23268 on the driver's side and a 23269 on the passenger's side.
Specialty Products Company | SPC Alignment | The Automotive Alignment Leaders

A 2.5 inch lift on a 38" long radius arm will change caster 3.7 degrees. The spring/sleeve will result in an overall caster reduction of about 1.25 degrees (1.1L, 1.4 R)

Alignment spec I found are:
caster 3.3 (normal) 2.2 (heavy service, camper/snowplow) +/- 1.3
I assume the difference is that the heavy service springs cause the front to sit higher hence reduced caster.

If my truck came from the factory right at 2.2, the spring/sleeve should put it at around 0.8 to 1.1, which is technically 'in spec' but on the bottom end.

For the least amount of wander and best road manners, I would like to be at least 3.3 degrees, and ideally more like 4. Prehaps I will only get 2" of lift from these 2.5" springs as I already have the heavy service springs, which would impove the situation slightly.

Hopefully this info can help someone determine if these sleeves are suitable for their truck and acceptance criteria.

 

Thanks! Are you going to get a wheel alignment to see where the sleeves put you at?

I don't know about the current SD, but Ford used to have different sized sleeves for different spring packages to adjust the caster.
I would agree with you on having more caster than not, just adding that you will probably want a stronger steering stabilizer (it can cause more kickback while off-road), and if running much larger tires it can put quite a bit more load on your power steering/make it feel heavier.
Your target range seems fine however.

 

I'm still on the fence whether to install these sleeve or not. I have several options:
a) install sleeve and live with poor caster and wander
b) install sleeves, modify radius arms for another ~2.5 degrees
c) Modify radius arms for 4 degrees. This would allow the truck to actually get an alignment.
d) Buy $$$$ aftermarket radius arms. No, I'm too cheap.

Installing these sleeves prevents any further alignments. They are fixed and at the max. Spending $100 to get an alignment would just be a measurement since the tech can't change anything (other than toe or steering wheel center)

Modifying the radius arms would involve moving the axle end holes. The bolt to bolt distance is about 7", so the hole needs to move 0.122" per degree. To get 2.5 degrees only the lower hole would need to go forward .300" For 4 degrees I would move both the top hole back and the bottom hole forward .244". To move the hole I would weld a thick washer in the new position, from the back filling in the old hole.

 

You could go with these from BD Diesel. BD Power - Product: Cam Caster Adjuster Kit

 

Or use radius arm drop brackets and do not use the sleeves. You would get at least 4° using the drop brackets since the brackets are designed for a 3.5-4.5" lift. Less lift, more caster.

 

Good point. I had started down that path however one of my goals is to keep the suspension looking as close to stock as possible, and the brackets are fairly expensive ($300).

So I decided to pull an arm and tack some washers in place. It this point I am not committed and decided to go slow and be confident with what I'm doing. The washers are about the same size as the bolt head/nut so they will not really be noticeable.



Area to fill with weld on the bottom, and grind on the top.

 

I put drop bracket's on for a 3" lift. $150 off eBay. Toned the darting way down, way more than the dual steering stab's did. Took about 15 minutes to install.

 

was going to tell u I tried the sleeves and they suck. spent 1k on radius arm mods and I love the steering feel now....

 

What mods did you have done? Pics?

I went ahead did a 4 degree tilt to the bolts. It was fairly easy job about a half a day. Installed you cannot tell the work was done unless you did the job. Now I can actually get an alignment done, and still have full adjustment range.

 

I ll get pics. I have 10" wide rims so the sleeves pulled the caster back at the top making my tire hit the fender. By using the radius arm mod it pushes the castor forward on the bottom. it does hit the bumper bit I Fab d spacers and pushed the bumper out.