Troy,

What's the latest on your "thunker"? Any more you can share with us, dude? BTW, I sent you an email, read it before posting here.

Later,

~DM~

 

there is nothing new to report. i'm still waiting for the regional rep to show up and look at my truck.

 

Keep us posted Troy.

RP

 

I skipped page 6&7 of the threads, so I don't know if it was posted but I put the Thunk TSB into a PDF, and posted it on my site for ya to download....

Here's the Thunk TSB

 

A buddy of mine owns a tranny shop thinks there might be a vavle internally that needs to be adjusted by a pro to reduce this hard shift thump, I'm not too sure if that is the cause or not though.

 

My tranny has clunked since day one. The transmission was pulled out a month ago for a totally different issue, the weld on the driving shell let go and I had no second and no reverse. The entire unit was disassembled and repaired and reassembled, transmission is working okay now, all except the clunk is exactly the same as before. Bear in mind, this is not the same "thunk" from a dead stop that I think this thread is concerned about. The clunk happens when going around 20-25 mph and let off the gas like when going around a curve in a subdivision, clunk every time.

I think it's excessive drive line slop myself, that spring they talk about in this TSB is something different and unrelated I think.

That's my 2 cents worth.

I'm running a Transgo shift kit now and the shifts are real nice and firm as well as crisp, the thunk from a start is much less than before but I'm not sure why.

~DM~

 

The thump is from the rear end. The LS is locking and unlocking. We have located this on the dyno. Ford gives the normal OH WELL. I run the baumann shift kit (any will do) as it holds the gears longer (thus putting pressure on the rear end). I am also running RP 75-140 in the rear. My thunk is all but gone. This is caused by the tranny releasing when coasting. When it does the rear end goes into a no pressure setting. When you get back in the throttle the rear end relocks and whamo (thunk).

Another test is to turn in a right turm pattern at 25. let off enough to cause a non affect (no positive or negative pressure) then get back on the gas (thunk)

 

Skid,

I won't disagree with you as I thought the rear end was making the thunk from the begining, however I've been chasing it all around the truck and it always seems to come back to the driveline. However, there are folks who claim they don't have the LS differential and they still have the "thunk". Knowing that not all "thunker's" have the LS differentials makes for a difficult time convincing everyone that it's the rear end.

I would like very much to get to the bottom of this issue, what do you think can be done to fix it? Are you saying different differential lube will cure the problem, or a combination of things, please elaborate more as there are scores of owners who want this PITA problem to disappear.

Thanks,

~DM~

 

I do NOT have the the Limited slip on my truck and I still get the thunk....just an FYI.

'01 F150 Screw, XTL 4x4
5.4 v8

 

okay, here's the latest on my thunker. yesterday the local ford garage put a new '03 transfer case on my '02 truck. they grabbed one of their '03s off the lot and went to town. a field engineer who is dealing with my issue recommended trying this first...or at least before he shows up in december. i'm not sure if he knows something i don't in reference to '02 transfer cases, but at least the local shop is finally doing something about my clunk/thunk rather than sitting back and doing nothing!

anyhoo, for the time being my truck is no longer thunking!! however, only time will tell weather this works in the long run.

btw, the reason they opted to install a new transfer case is because they think there was an incompatability issue between the output shaft on the old transfer case and the slip yoke on the driveshaft. apparently it's easier to just swap out a transfer case vs swapping out an output shaft...

regardless of what happens, i'll keep you guys informed...

also, my thunk was related to pulling up to and taking off from a complete stop, not the tranny thunk some of you were talking about...

 

I'm just glad to hear you guys discussing the "Thunk." I bought my '01 Screw a few months ago at 22k and now have 28k on it. The thunk has bothered me but I have not had a chance to get by the dealer. We have speed "humps" in our neighborhood (like bumps but about 4 or 5 feet wide). When I slow for those and then accelerate, it thumps hard.

 

I'm running out of time... pushing 30k miles. Anyone have a solution?

 

It's definately not exclusive to a 4wd because mine is still doing it pretty badly...

Seemingly worse actually...

RP

 

Mine too. It's getting worse. I plan on pushing the issue again at the next oil change/dealer visit. I'm at 27K.

I hope someone finds a solution.

Tom

 

Hi Guys,

Sorry to hear about your driveline problems. Sounds like several of you are having luck getting it taken care of with a different chip.

I have access to "AllData" and presently there are no tsbs with regards to any driveline noise. Only one I noticed was for the ranger model.

I have no doubt that it will get fixed-maybe even here. Best thing everyone can do is try to find a solution that works. You will not have any luck screaming at the dealers or factory personnel. If you are not getting an appointment with your factory rep, go up the chain of command. Don't be unreasonable though, they are just not going to start throwing transmissions, etc. at the vehicle. Remember, they sell well over 1/2 a million of these a year. It would add up to a huge recall campaign.

Good luck and I will keep you up to date if I see any new tsbs.