when reverse the front tires goes /---\

[F 150Cobra]

jacked it up... try to wiggled it back and fort.. up and down.. but nothing!! stable !! im blaming the coils to!

 

[DNFXDLI]

If it is only happening in reverse, it might just be a function of the twin-I beam geometry...I've noticed that in even new vehicles when reversing with the wheels turned hard over one way.

 

[1985 Ford F-150]

Id say its fine my 85 does the same thing and I just replaced the front springs and shocks last year.

 

[Fellro]

My 250 does it as well, no coils at all. If it would be anything, it would be the bushings at the frame or track arm bushings, but I also do not have track arms. The coils only hold it up. The nose dive test doesn't really provae anything about the strength of the coils, more about the shocks than the springs. Ride height will tell you if your springs are weak.

 

[rickpilgrim]

The brake dive test just confirmed what I thought. I just went 35 mph, hit the brakes hard but not locked up and BANG she went right to the bump stops. Of course that was shocks also even though they passed the driveway "bounce" test. After changing springs/shocks it went away, meaning you could back uphill out of my basement shop and no longer notice the wheels changing camber. BTW, I used 302 springs as they have 1 more coil than the 300-6 ones, or so NAPA told me.

 

[1985 Ford F-150]

If ya want even stiffer springs you could get some for a super cab.

 

[surewhynot]

If it is only happening in reverse, it might just be a function of the twin-I beam geometry...I've noticed that in even new vehicles when reversing with the wheels turned hard over one way.

Duncan is right. It is the geometry of the twin I beam suspension. All of them do it to some extent. Having soft (worn, weak) springs will exaggerate it, but they all do it.