Doing the 250-350 rear block swap. The F350 rear Ubolts I got are almost 15" long, it seems like with them new bigger 4" blocks, I will run out of threads i.e.) the new 15" ubolts are too long? Any ideas? Am I missing a leaf spring?

 

Seems like maybe I dont have the top helper spring? Is this modification only for trucks that have this spring?

 

the 350 has a bigger axel so u will need the u bolts for a 4in block for a 350 ford has atleast 4 differnt part number for 250 and 350 for 2 and 4 in blocks they are listed in metric so when you look on there comp. it will be in metric

 

Seems like I have the opposite problem, the 350 ubolts are too long, when going to tighten the nuts down I actually run out of threaded bolt before they are tight. It seems like my leaf packs are missing the top helper spring?

 

ya if you dont have the helper spring like the duallys u will need the shorter ones for the 4in block without helpersprings. many differnt sizes just measure how much less they should be then convert it over to metric and something close will come up on there screne

 

Thinking i might just skip the 350 blocks and do a 2" add a leaf. At least that would get the job done and maybe add a little load capacity?

 

So here is a bad picture of my rear leafs, am I missing a leaf? 06CC SB4x4.

 

Looking at my rear spring you can kind of see when the center of the spring pack sits on the block and almost bends back the other way, does this mean they are worn out? Ie the arch is killed.

Would the add a leaf fix this?