I've fitted a replacment sammy leaf spring front axle on my vitara... yes vitara.... as i broke my last one.  :( 
Now i've got the wobbles at a speed approx 40mph  :( 
I run 35x 12.5 inch tyres.
Would it be because i need to refit the steering dampner  :?: 
or do I need to strengthen the axle ( old one was) ?
Or is it something completely different   :?:  :?: