I have a 06 SCrew 5.4 4x4 with 77k miles on it.

Just recently I've notice it shudder/lunge a bit when moving slowly and turning (like going into a parking spot). No CEL or anything and is fine while running at higher speeds in 4x2 and all the 4x4 settings.

It is only when I turn and am going slow that it feels like you are going over a speed bump or some object. Hard to tell if its coming from the rear end or front transfer case. Almost like something is catching then letting go when you give it a little tap of power.

Seems like there are quite a few issues/noises from searching with the rear end/tranny and fluid/friction additives. I couldn't quiet pinpoint what I was looking for on my searches so not sure if its a similar problem or not.

Since its getting about time to change all the tranny fluids anyway and the truck has the 2yr ext warranty, might just see if that fixes it? Any ideas?

 

Maybe your LS clutch pack in your rear end is going? You should not have anything going on in your front diff if you are not in 4 wheel drive. Maybe a cv joint going bad, but I doubt that would give you that feeling.

 

What exactly is the LS clutch? Heard of it, but would like to know more about it please.

 

Limited Slip Clutch, in the rear diff.

Anyway, have you checked the fluid in your power steering pump? Had and older sportTrac that would do the same thing when turning into spots. Ended up being dirty fluid in the resevoir. It was like the pump would slow the accesories down a bit causin a hesistation in the motor. Just an idea.

 

Before I would change out the clutch pack, I would do a replace of the fluid and friction modifier. Especially at 77k. This assumes he has a LS diff.

 

Yea I figured 77K was a little premature.

 

No matter what, it is always cheaper to try the fluid change first. Clutch packs are not cheap, unless they are under warranty. And the normal fluid change is 100k.

 

Thanks for the information guys. Yeah I've looked at the scheduled maintenance for the 75k and 80k mile marks. I bought it used so I think I'll do the safe thing and just check and change all the fluids for it. If it blows, its under warranty. Plus it puts me at peace of mind since I know what maintenance was done and doesn't leave me guessing.

We'll see how it goes. No problems today, but was only in 4x2 since the snow isn't bad anymore.

 

hey there gunmetal my truck just started making a wierd vibration when i turn at slow speeds, i was going to change the front diff and rear diff to, ill have to check with the power steering, so what did you end up doing and how do you change the power steering fluid