Do rear ends REALLY flex like this?!

[Josue]

Came across this pretty cool video showing how hard your suspension is working beneath you, and the difference between old worn out shocks, and new shocks.

At 3:40, he shows how much his rear end flexes, or pivots, under acceleration. Granted, this is a truck, with the springs over the axle, but does the same hold true for older suspension designs? If so, I can certainly see the benefits of all these Torque Arm rear suspension setups now!

http://www.carthrottle.com/post/1bxxX/

[Striker2237]

Oh yeah, I have personally seen 1200+ LB/FT diesel trucks wrap the heck out of their leaf packs......6 leafs WITH a pair of overloads at that.....It helps greatly to bind the front of the pack (to an extent) and add a half leaf to the front of the pack to control the axle. Or if you don't care about being a sleeper just get traction bars I guess.....

[Schwartz Performance]

This generally applies to leaf spring vehicles only, because there's nothing else holding the rear end in place. Any type of rear suspension with solid bars/links rather than leaf springs will have a much less dramatic effect. Torque arms aren't the only solution.

-Dale

[Josue]

Is there any way to "solidly" plant the rear end in place, so it doesn't move one single cm? Or is some movement ok/necessary?

Is here any performance lost in having a rear end move around that much?

[pist0lpete]

Ultimately leaf springs will always be a compromise. For forward bite you can install cal tracs. For handling you can do solid bushings and stiffer springs but the rear will still move more than a 4 link setup with a panhard bar or watts link.

[Josue]

Is there some movement still with a 4 link and panhard bar/watts link? Or do those items pretty much lock the rear end in place?

[BMR Sales]

Almost all of that was Axle Wrap. Of course it doesn't help that the Shock is rusted thru!

[BMR Sales]

Is there any way to "solidly" plant the rear end in place, so it doesn't move one single cm? Or is some movement ok/necessary?

Is here any performance lost in having a rear end move around that much?

Oh, sure you could do that, but you would end with a Flintstone mobile! Or a Buckboard Wagon!

You have to have movement so the suspension can articulate.

Performance loss in that Video - absolutely!

[Schwartz Performance]

Is there any way to "solidly" plant the rear end in place, so it doesn't move one single cm? Or is some movement ok/necessary?

Is here any performance lost in having a rear end move around that much?

The shocks do have to move. Weight transfer is important too, so if there was no movement it wouldn't transfer the weight to the rear of the car effectively. Search youtube for drag racing rear suspension videos, and watch the launch.

[Josue]

Gotcha!

Ya learn something new every day! haha