I'am restoring a TT Truck, this truck has a double wishbone. Is this original? It could be a combination of an early and a late axle.
It's a reinforced early style over the axle wishbone. Do you have a very early 1918 TT truck? They had the over the axle wishbone, but frequent failures made it inevitable for the stubborn Ford to make a change to the stronger under the axle style in 1919, only for the TT trucks at first, so it was likely the heavier duty they had to suffer that was the main reason. So even if the reinforcement isn't original, it's very wise to keep it as it's even stronger than the later style
Looking at your picture again, maybe it isn't really an early style up to 1918 wishbone, it looks more like a 1925-27 English made drop frame wishbone with an additional reinforcement made from a US 1919-27 under the axle wishbone?
The english late over the axle wishbones are as strong as the late US style since they're fastened by cones in the perches, much stiffer than the bolts through the perches on the earlier ones.
Looks strong, perfect for someone who wants to put front brakes on
I think Roger K's second post is spot on!
The ball and center castings do not look like the earlier wishbone styles.
Unless you have a specific target that you want to match perfectly, I would use it.
Drive carefully, and enjoy, W2
On our Canadian sourced cars the forged Y and ball at the rear had those longer "legs" on the later over the axle wishbones. Early wishbones had the tubes terminating almost at the ball.
That same Y forging with the longer "legs" carried on into the below axle wishbone.
Allan from down under.