Diagnosing? Light shudder (anyone have this)?

[Blu21]

I have a similar shudder on my 2014 w 121k in low idle/low gas. Just started for me the last 1-2k miles. Replaced breaks and all 4 ball bearings recently at the 120k oil change. Not sure if it started before or after that fix, honestly probly after. My shudder doesn’t necessarily feel like it’s in the rear.
Idk if this helps- if someone finds a fix tho I’d love to hear about it- otherwise it’s really not that big of a hassle/annoyance

 

[WNCHSTR96]

Yes, that can be a concern on high mileage vehicles. The transmission fluid replacement interval on these trucks is 150k, so you should be fine.

150k!?! Is that right? I could of sworn it was 60k? I totally trust your judgment, but I don’t remember it being that high? I guess I read it wrong somewhere and have stuck to it. I have changed the fluid in mine 4 times now! FWIW I don’t experience a shudder.

 

[FordTechOne]

150k!?! Is that right? I could of sworn it was 60k? I totally trust your judgment, but I don’t remember it being that high? I guess I read it wrong somewhere and have stuck to it. I have changed the fluid in mine 4 times now! FWIW I don’t experience a shudder.

Nothing wrong with doing it earlier, that is just the maximum service interval under ideal conditions, which for most of us don’t apply. So if you’re towing, hauling near or at max payload, or running your truck hard, or operating in high or low temperatures, it would be advisable to change the fluid well before the maximum interval.

 

[PD1744]

Following. I've always had this issue. Tons of maintenance done. Everything seems to help a little, but nothing has cured this. Feels like a lumpy idle at times. Sometimes nothing. But barely lifting off brakes and starting too idle roll it's very prevalent. I'm starting to lean toward torque converter or motor mounts. Have also read it's 'normal' due to the cam, but I've also heard people say they don't have it.

 

[Jakenbake]

Keep in mind I have made quite a few changes in a shorter amount of time that could have “fixed it”, but I can’t be positive what it was.

I believe changing my leaf springs to deavers we’re the one that more or less “fixed it”. I use air quotes because I don’t notice it anymore and I’m not sure if it was an actual problem.

Assuming the issue is an axle wrap from taking off: I also have 3.5” bypasses which probably help control the axle some.

I have also changed my trans fluid and filter which maybe that did it.

Installing traction bars would be a good way to test my theory on feeling the axle wrap. My guess is it is a pinion angle “shudder” you are feeling.

Note that traction bars are not cheap and I’m not saying just throw money at the problem. But traction bars are nice soo….

 

[SCSVT]

Update: new rear brakes, still have the issue. In addition, I have a vibration that hits at 50mph and goes away at 70, then re-emerges at higher speed.

Talked with a grizzled mechanic friend and he is suspecting ujoints or driveshaft balance. There is a little play at this slip joint / bearing area of the rear shaft. Hmm.

 

[Canuck714]

I’ve heard concerns over changing trans fluid at high mileage, hate to do that if I can’t verify it was done at least once in the trucks 90k life… unsure

Don't be afraid of fluid and filter change, just don't ask for a flush that can dislodge stuff and create other issues. And 92k on a 12 is not what I would call HIGH mileage..

I think 11 and 12 have a Recall TSB on the driveshaft. Maybe yours was not done.

RAPTOR—DRIVELINE CLUNK OR CHIRP/SLIP/BUMP TSB 11-5-7
ON ACCEL OR STOP—BUILT ON OR BEFORE
03/12/2011
FORD:
2011 F-150
ISSUE WARRANTY STATUS: Eligible Under Provisions Of
Some 2011 F-150 Raptor vehicles built on or before New Vehicle Limited
3/12/2011 may exhibit excessive clunk or a Warranty Coverage
chirp/slip/bump condition from the driveshaft on IMPORTANT: Warranty
acceleration from a stop or when bringing the coverage limits/policies are
vehicle to a stop. not altered by a TSB.
Warranty coverage limits ACTION are determined by the
Follow the Service Procedure steps to correct the identified causal part.
condition.
OPERATION DESCRIPTION TIME
SERVICE PROCEDURE 110507A 2011 F-150 Raptor: 0.4 Hr.
Replace The Rear
1. Remove and discard the existing driveshaft Driveshaft Assembly. (Do
assembly. Refer to Workshop (WSM), Section Not Use With Any Other
205-01 Removal and Installation labor Operations)
Driveshaft-Rear, One Piece. DEALER CODING
2. Install the updated driveshaft assembly. Refer CONDITION
to WSM, Section 205-01 Removal and BASIC PART NO. CODE
Installation Driveshaft-Rear, One Piece. 4841 42
PART NUMBER PART NAME
BL3Z-4602-J Driveshaft 145! Wheel Base
BL3Z-4602-H Driveshaft 133! Wheel Base
N800594-S100 Driveshaft Flange Bolt (4 Req)