clunk in reverse 2006 expedition XLT

[Fidder]

Hey all, looking for any advice on what might be wrong with my Expedition, It makes a clunking sound when accelerating in reverse right after shifting into reverse, the sound does not continue. it generally only makes the sound when hitting the gas, it does not seem to make it upon shifting. and I like I said it only makes the sound once. It will not make the sound again unless you put it in drive, move forward a little bit and then put it back in reverse and backup.

Would love any advice on what that might be.

thanks,

Fidder

 

[stamp11127]

I'd recommend an inspection of the u-joints, yokes and transmission mounts looking for evidence of wear or missing bolts/nuts.

 

[trkinspector855]

I'd recommend an inspection of the u-joints, yokes and transmission mounts looking for evidence of wear or missing bolts/nuts.

What he said.

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[Habbibie]

I'd recommend an inspection of the u-joints, yokes and transmission mounts looking for evidence of wear or missing bolts/nuts.

Exactly that^

 

[JExpedition07]

Normally U-joints will clunk when the shift is made, but anything’s possible.

 

[1955moose]

U joints klink not clunk, they can clunk, but usually when real bad, at least that's been what I've run into. Old Dodge 100/200 series vans were famous for it. Clunks can be anything from motor mounts, to worn innards of transmission, to as Stamp stated loose bolts/parts. Isolating the clunk is the fun part. Jack/rack it up, and carefully isolate your noise.

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[Fidder]

Thanks for the advice, I did go under and did not see anything apparently wrong with the drive shaft, yokes, or u joints. The transmission mounts also looked to be in good shape.

I also just had the engine replaced with a reman and the guys at the engine shop said they would to a good shakedown and check all mounts before they put the new engine in it so I am thinking that is probably good to go there also.

When looking at it, it does appear that the rear diff is what is moving to make the clunck. At first I thought it could be the rear differential support bracket bushing, but, I am not so sure that is the case because the bushing side of it does not seem to move at all when it clunks, The only thing that moves is the differential itself and it is not a huge movement.

 

[JExpedition07]

Does it just make the noise or do you get a shudder through the whole truck as well?

 

[Fidder]

Does it just make the noise or do you get a shudder through the whole truck as well?

The clunk is both heard and felt.

 

[Fidder]

I am starting to this that the it might be related to this TSB

TSB 05-16-10

08/22/05

CLUNK/GRIND/THUMP NOISE - FRAME REPAIR PROCEDURE

FORD:
2003 Expedition
2005-2006 Expedition LINCOLN:
2003 Navigator
2005-2006 Navigator ISSUE
Some 2003 Expedition/Navigator built 3/18/2003 through 9/3/2003 and 2005-2006 built 8/2/2004 to 6/13/2005 may exhibit a clunk/grind/thump noise from the rear of the vehicle. The condition will occur when the transmission is shifted, the vehicle changes direction, or on acceleration. Vehicles may also exhibit a vibration from the driveshaft/axle area. This may be due to missing or damaged attachment bolts that secure the rear torque arm to the axle housing. In rare cases, if symptoms are ignored and the bolts are allowed to completely disengage, the differential may tip upwards allowing the driveshaft to make contact with the frame.

ACTION
If frame damage is found, a service kit is available to repair and reinforce the frame. Refer to the instruction sheet included in the kit.