I was discussing this earlier at work....

I have a question for you guys suffering from this- does anyone who has this issue have a 2 wheel drive vehicle?

Myself and some other associate techs have our suspicions about certain components in the transfer case. Just gathering information

 

Mine does it in my 2005 E-350 van and it 2 wheel drive.If ford is going to say this is normal,thats Bull.Its got 1000 miles on it and I somtimes let of the pedal when it shifts that gear because im afraid somthing is going to break. Other than that no problems yet I absolutly love the truck.

 

I have an 03 F450 two wheel drive. Been clunking for 10,000 mi. at least. Have about 18,000 total.

 

The interesting thing about 'both' of these clunks is, that it doesn't seem that anybody notices it on the test ride, it's not there, OR, it's at least not there upon delivery and seems to develop within the first few hundred/thousand miles.. Which for me, 2-3 hundred miles (when it was first 'slightly' felt) would be around 5 warmup cylcles.. This leads me to believe that it 'may' be a combination of hardware, and the learned shift strategies.. My 03 didn't have it when I test drove it, and I made REAL SURE it wasn't when I drove the 05 before trading the 03 in.. I drove the 05 in all operating temps and throttle loads many times over about 30 miles or so in a couple of days.. NOTHING.. Perfectly quite and timed shifts.. Now the shift patterns have changed, (liked'm better before the change) and have developed a mild clunk on the 2-3 upshift only.. No roll away 2-3MPH clunk on the 05.. Seems that the PCM/TCM would have to have a builder loaded driving strategy installed, or the shifts would be similiar to the 'touchy' shifts after the tuner loads when the KAM is cleared..

Plus, now with the gassers getting the 5R110 we should see alot more in regards to this issue.. Maybe enough pressure to get Ford to have a good look see...

.....................HP...................

 

I wonder if disconnecting the batteries and go through the relearning strategy will make it go away for a while?

 

We need someone to try it, it cannot hurt trying it.
Could prove very valuable to all who do have the "clunk"

 

I'll try it this weekend. Seems I was playing with the Predator after the latest flash. I hadn't noticed the clunk for a while. Didn't correlate the clunk with relearning process. I'll go do the disconnect for 10 minutes and then go through the learning process and see if it clunks.

 

Well to save everyone some trouble with unhooking the batteries it doesnt help my 04 clunks quite often and my airbag came loose making my horn go off so i unhooked the battery to locate the prob and pulle the horn fuse.hooked up the batteries and clunked down the highway to the dealership.

 

I am beginning to think some of us are talking about different clunks. Mine clunks once. After warmed up and driven, park for a while, back out of parking place and roll forward. At about 2 mph it will clunk, sometimes loudly, sometimes lightly and sometimes not at all.
Here is a service bulletin on this:
There was another bulletin on clunk on 2-3 shift for 04 built during a certain period.

Sure we are talking about the same thing?

 

Thats why it seems to be, as if, a driving/shift program was loaded into the PCM/TCM when built, and is replaced with the 'specific' adapted strategy.. But if cleared, or overwritten, its gone!! And then 'clunk'.. Mine came on very slow..

..................HP..............

 

Same here. I didn't notice it until over 3500 miles.

 

Whats odd is, that one unit will have no roll away 2-3MPH clunk, and will have the 2-3 upshift clunk instead.. Or can/will have both, or none at all.. If it were an excessive clearance/setup issue, than it should have been present from new.. And it should be somewhat of a constant as the trans warms, although should quite as the metals ect. heat and expand.. I can let mine completely heat up without driving it, and it still needs to 'clunk' a few times (usually less noise with each shift cycle) before quieting.. After it gets'm out of it's system, it's smooth until a sit time, or cool down.. But with my 03 and the 05, all the clunks 'sound' were alike..

.......................HP.....................

 

My truck didnt make the noise till after I had a couple kmiles on it. And this may be related but i am not sure. When you slow down to make a turn onto another road and you get back on the accelerator it violently engages back into gear.