I am getting a shutter as I start to accelerate and the same shutter at the end of a stop. At the stop it is like a disipation of stored energy or something. It is hard to explain. The local dealership can't find it. I have a 2000 F150 4x4 with a 4R70w and 84,000 miles. It runs great above 15 mph. I just don't want to let something continue and cause a bigger problem. Help.

 

I am surprised that no one out there has replied to my original post. The shudder is driving me crazy. I have ruled out the rear diff., the drive shaft u-joints, and the tires. Help!

 

Change the transmission fluid.

 

Is the shudder like a clunk or does it last for more that one clunk?

 

Hi Short Circuit,

I have had the same issue you describe almost since my truck was new. It seemed to start at about 25000k. There are two distinct parts to this problem. First, when applying very light gas pedal pressure it feels as though the truck is "hopping, or bouncing". As soon as the truck starts moving more than about 10kph it goes away. The second part is when stopping. When coming to a stop and the truck shifts into first gear (no clunk) it seems as though there is some centrifical force that the truck is trying to counter act. The effect is the same type of "bounce", usually about 3-4 times (very quickly) then it stops. I have spoken to a number of mechanics about this, some say it's normal (although it didn't do it when it was new), others have said it is the leaf springs binding up under the stopping force. The effect does lessen a bit when the truck has a load in the bed. I have had my extension housing replaced, balanced the driveshift, rebuilt the differential, replaced the shocks and had the tranny fluid changed using the machine that hooks up to the rad and the problem is still the same. It has not gotten any worse over time nor gotten any better. My "gut" feeling is that it has something to do with the torque convertor.

My next step is the have a tranny service done (replace all the fluid and change the filters)

I would like to finally put this issue to bed but have never been able to find it. Hopefully some great mind here could shed some light on this.

Regards,
FStrike

 

Thanks for all of the replies. All of the things that FStrike talked about followed my chain of events to a "T". The same explainations from mechanics (Rear Diff., Drive Shaft, Leaf Springs, Tires...). My next step is a fluid flush/change and a filter change. Fstrike, believe me I work for Ford and we actually build the F150 and the feeling that we are getting is not normal. I have atleast a dozen friends driving the same style truck and I am the only one having this problem. I'll let you all know how the fluid and filter work.

 

Update to this ongoing issue:

This weekend I picked up some Seafoam and (thanks to this forum) followed the quidelines on how to appy it (through the brake vacuum hose).

Now for the interesting part.. call me crazy but it seems as though the truck is shifting better and the shudder at stop is noticeably less (still there but almost negligible). I'm just wondering if anyone here could pose a possible explanation for this? The only thing I can think of is better cylinder firing during shifting. Would this make sense?

FStrike

 

Just an update...I had the fluid flushed and replaced w/filter and additive. Shudder did not go away or change.

 

Hey Short Circuit and others,
I'll try to keep it short:
2001 F150 XLT, 4WD, Flareside, 5.4L.
I've had the truck a little over two years, purchased used with 18k miles -- clearly an un-abused truck.
Imagine driving through a neighborhood, maintaining a slow speed of around 18mph, give the throttle a little push to keep moving, it seems like the transmission floats between 1st and 2nd gear. Then as enough power is administered, the transmission finally finds 2nd and a definite 'slam' is heard. I took the truck in to the 'transmission specialist' at a Ford dealership and had him ride with me; I was able to repeat the slam at 18 mph consistently. (the shudder wasn't present then)
He told me that those characteristics were 'normal' and didn't want to investigate further.To complicate these syptoms, I also experience the shudder when taking off from a dead stop, but nothing when coming to a stop. The shudder doesn't happen ALL the time, but it seems to mostly happen in the first 15 or 20 minutes of driving. I had the fluid flushed in Dec. 2004 with no effect to get rid of slam or shudder. I have also noted that when driving at slow speeds, say like a parking lot, and turn a 90 degree turn, I appears there's enough slop in the rear end to make a sound like the axle(s) are moving out to their maximum play?
It beats the hell out of me what is going on with my drive train, but it seems like I've got a full compliment of issues making it difficult to isolate each problem.

As always, suggestions and advice is appreciated.

 

Sorry but a dealer mechanic telling you it's normal is B.S.
I bought mine at 34k miles and is perfect working, now has 45k miles. Change the fluid and still perfect.
The test for engine or trans/driveline, coast down to a stop in neutral. If you still have a shake, it's driveline..
BUT, you can't fix anything if there is no attempt to isolate the problem and be willing to foot some expense of the exploration for diagnosis.
After all, most doctors can't tell much by just looking at you from afar and it still cost's to even do that!

 

The slam between first and second gear sounds like a broken accumulator spring. I had that problem two years ago. If it is, don't let it go too long. The broken spring can cause scarring in the transmission casting and could cost you a total rebuild. As for the shudder, I am at a loss. I think I am going to drive mine until it breaks and then repair whatever is broken. I have a feeling that it is my torque converter now.