Skandocious

Okay I know there are tons of shuddering threads and I've read most (if not all) of them before making this post... I've got a slight vibration on take-off and I want to see if anyone else has this issue.

It happens only when accelerating from a complete stop and happens very shortly after putting my foot on the accelerator. It's most noticeable on moderate-to-hard acceleration. It's a quick vibration that lasts less than a second; it's maybe 3-5 feint shakes that feel like they're moving side-to-side, similar to what you might feel if you bog down a car with a manual transmission when you don't give enough gas as you feather out the clutch.

I know there are many types of shuddering/vibrations that people are reporting and often times these threads get clogged up with people who think their issue is what the OP is talking about. So I want to clarify that my problem is NOT one of the following:

1) Shake going to and from a stop. I had this one already and they cured it by lubing the driveshaft slip yoke. It was a much harsher/quicker vibration than this one and it happened RIGHT as I came to or left a complete stop.
2) Shudder at much higher speeds (eg, 50-60 mph). I've read a lot of threads about people driving up an incline at speed and feeling misfires, or something similar.
3) Rough idle/misfire. I do also have this issue but I feel that it's unrelated (though I could be wrong).


I've had the truck into the dealer several times and they're completely stumped. Things they tried:

-Replace rear spring blocks according to TSB 11-9-17 (full text here)
-Replace entire rear driveshaft assembly
-Replace torque converter
-Check all driveline angles with driveline angle measurement devices

They even called in the field service engineer from Ford to take a look at the truck and he was stumped too.

I feel like this might be axle wrap-- I've been in trucks with fairly severe axle wrap and I know what it feels like. If this is axle wrap it's VERY slight.

Any ideas? Anyone else have this issue?


My truck:
2011 F150 FX4 EcoBoost SuperCrew 6.5" bed (the LONG one), Build Date 5/19/2011

Skandocious

Anybody? I'm really stuck on this one since the dealer has basically given up...

z06

My 157" wheelbase truck does the exact same thing. Friend that has a 2010 drove it the other day and mentioned it also. Has not been to dealer yet. Not looking forward to going either. Seems to be a very low fix rate for these problems. I do also have the miss at 60 or so.

dcfluid

Extensive discussion on your problem. It is axle wrap. I have had the spring blocks done also and the next step is the springs. I will post my thread here and how a traction bar fixed the issue.
Just wait until you tow a heavy trailer, then you'll feel a shudder to remember.

dcfluid

Acceleration shudder diagnosed by Ford.

Read thru this for lots of info.

ECinc.

Happens to me. I never really noticed it until I had a heavy load in the bed, then I really felt it. I figured that it was axle wrap. I notice it a little when the bed is empty and it really doesn't bother me a whole lot then. I don't know maybe it should? 2011 Screw 6.5' bed 4x4 5.0

Skandocious

I have already read through most of that thread-- it left me feeling like my problem wasn't the same as yours but perhaps I'm mistaken.

But I did forget to mention in my first post-- the shudder is slightly more pronounced when I have a full tank of gas. Haven't had a chance to hook up a trailer yet cuz my boat is in storage for the Winter.

BUT! I did do a test on the way home tonight. All of a sudden I realized I had a position on the shifter for 2nd gear, which will start my trans in 2nd coming off of a stop (read: less torque!). So I started in 2nd, and of course the truck felt like it was having a harder time getting going because of the lack of torque, and guess what! No shudder! Sure seems like the shudder is related to loading the driveline, which most likely means axle wrap...

Really pisses me off because I suggested axle wrap (amongst another things) as something for the dealer to look at and they just ignored me and my ideas.

dcfluid-- you mentioned that the next step in the TSB is to have the springs replaced. I brought that up to my dealer and they told me that my truck already has the "new springs." Do you know why the TSB calls for new springs? Is it a different part than what comes on the truck? I'm wondering if I can cross-check my springs against the part number in the TSB and if I'll see a discrepancy. But if they're just replacing the springs with the same part (ie, replacing a defective part) then the numbers would match up anyway...

EricTheOracle

Everybody with the 157" WB truck has a slight shudder on take off.

dcfluid

I think Ford was grasping at straws with the spring change as it MAY reduce SOME of the shudder.
You want to test without a trailer? Stomp on your ebrake and take off at full throttle. That will load your drivetrain to simulate a trailer pull. It works for me. It should magnify the shudder thus revealing it as torque induced spring/axle wrap.

Skandocious

Against my better judgement-- I tried this tonight, and surprisingly it didn't make the shudder worse... I almost wonder if having the breaks applied somehow keeps the axle from wrapping more...

Now I'm starting to wonder if it IS axle wrap after all...