Rear end bouncing

[Geoff941]

At 45 mph the back end bounces. I've had the tires indexed, balanced, rotated, and aligned. Still at 45 it bounces. At 50 mph, smooth as silk.
I thought I read something about this happening to crew cab long beds.

Any idea on a fix?

[Jim@StreetLethalPerfrmnce]

from what i read most of them do it mine does it the same as you described yours. from what i have gathered its a driveline angle issue, and some have replaced drive shafts and it went away. like a lot of us, we just learned to deal with it. i can watch my bed bouncing in my mirrors...way to go Ford...

[phantom-3k]

Oh my god, I have the same damn problem, done everything from rotating, balancing, rebalancing road force balancing and it's still there. I never posted about it, thought it was just a retarded problem and didn't want to bug people. But it's good to know someone else has the same problem. Oh and it does not move when tires where balance or rotated. Maybe driveshaft? Or maybe a warped rotor or something... I wish I knew cause it does get annoying.


Sent from my IPhone when I shouldn't be!

[Enterko]

Mine does the same thing. CC long bed.

Funny thing is that when I tow, it goes away completely, so I'm thinking that I need new shocks.

[Clayton1985]

Havent noticed it, pretty obvious and not so subtle?

[phantom-3k]

It can be pretty obvious if you hit the 45mph mark just right, but it seems to be just at that point so it isn't as obvious as you would think. And you can see my bed bounce in the rear view mirror. But I am living with it for now, because I would rather have this then the "death wobble"!

[Tj Krawler]

Never noticed it. I'll pay more attention tomorrow. Maybe bad carrier bearings? I would think that would just get worse with speed though.


^ I do see the bed bouncing, but I just related that to heavy springs and the mirrors shaking.

[jesilvas]

Never noticed this, honestly.
At 70mph I can hit a bump and feel the 'echo' of the bump in the rear. I think it's shocks.
Guess I'll be driving at 45 mph tmrw.

[Geoff941]

Hooking the boat up and adding some weight to the back does cut down on the severity of the bouncing, but I can't tow the boat all the time.

[Clayton1985]

I have a vibration right at 40mph, but I think it might be the tires. I forgot about it til this morning on way to work. I first noticed it after i put the 35s on early last summer. Its fairly subtle though and not really concerned about it.