Update on 2000+ 3rd-2nd downshift Clunk

Lars Briedis · #1 08-21-2003, 12:36 PM

When I bought my 2001 Screw the transmission made a lound clunk from time to time when it when from 3rd to 2nd (or maybe it was 2nd to 1st) anyway it happens around 25 mph when you gas to downshift.

Anyhow I took it to the dealer and they had a TSB on the problem and they reconized my truck had a problem, but there was no fix for this. This was over a year ago.

Was wondering if there was any updates on this problem since it seems to be common.

I have 22k on the truck and want to get this resolved before the warr expires.

Does anyone know if the Ford 150 have a longer drive train warr?

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fx4x42002 · #2 08-21-2003, 10:45 PM

I just traded in my 2002 F150 that had this same problem. It would down shift kind of hard sometimes. Other times it seemed to hesitate a little before down shifting. I traded it on a 2003 Expy with the same transmission (4r70) and the Expy seems to be much smother. Of course I have only had it for a week and have been driving it pretty easy. But I have driven another 2003 with 9000 miles on it and it's transmission felt much better than my truck. I don't know if all this means anything, just passing on my experience.

Jono · #3 08-22-2003, 11:58 PM

I thought the Expys all had the 4R100 now?

fx4x42002 · #4 08-23-2003, 09:43 PM

I thought I had read that too, but my transmission code on the door sticker indicates it is the 4r70. I had hoped for the 4r100 just for the extra beef, but what the heck. So far this tranny feels much different and better than the one in my truck. I don't have an explanation for it though. The other thing I have noticed is this one idles really smooth and maintains a steady rpm. My truck idled a little rough most of the time. I don't have an explanation for that either. I guess just variations in the construction/programming.

greencrew · #5 08-23-2003, 11:23 PM

As I understand, that is the way the transmission was designed. It's an electronic trans with a coast feature. When you let up off the gas the coast clutch disengages and allows the truck to coast without the engine slowing it down. If you turn over drive off it won't do this.

When you start out, it shifts right away from first to second. As you get your speed up it shifts from second to third. Once you hit your speed the troque converter locks up. After that it shifts into over drive.

When you let up off the gas and coast the coast clutch disengages. I'm not sure what happens to the locked up torque converter at this point.

If you hit the gas hard, the coast clutch has to engage, and it has to shift out of over drive. The thunk is the coast clutch kicking in. They don't seem to happen at the same time, so after the coast clutch engages you get the delay from the down shift.

I have a minivan and a car both with the electronic trans, and they both do the same thing. The coast clutch is why you can let up off the gas on the freeway a mile before the exit and coast all the way there.

I have learned over the years to give it just a little gas to engage the coast clutch, then give er.

BarryAdam · #6 09-14-2003, 02:51 PM

Just got back from the dealer again with my '01 SCrew (4R70) after 4 visits for the "clunk".

Bottom Line is that Ford has a TSB for the 2-1 gear downshift and has a new re-designed planet support ring spring (TSB 01-03-07). Got one of those after the old spring was reversed and then a replacment tranny installed.

For the 3-2 gear downshift clunk/bump, the "Special Service Message" #16857 says "This is to be considered a normal characteristic, and service should not be attempted."

WHAT!!!! HELP!!!

Has anyone written FORD or gotten action on this one? I don't like it and am going to follow-up.

Barry

Xplorer · #7 09-14-2003, 07:35 PM

Here's the whole ssm for those that are interested

16857 2000-2003 F-150, E-SERIES, EXPEDITION ALL EQUIPPED WITH 4R70W TRANSMISSION - 3-2 DOWNSHIFT CLUNK/BUMP
SOME 2000-2003 F-150, E-SERIES OR EXPEDITION EQUIPPED WITH A 4R70W TRANSMISSION MAY EXHIBIT AN INTERMITTENT, SLIGHT, CLUNK OR BUMP ON A 3-2 DOWNSHIFT. THE CONDITION MAY GENERALLY OCCUR WITH THE VEHICLE AT A CRUISE, SLOWING TO A RANGE OF 5-20 MPH AND THEN TIPPING BACK INTO THE THROTTLE TO ACCELERATE. THIS IS CONSIDERED A NORMAL CHARACTERISTIC, AND SERVICE SHOULD NOT BE ATTEMPTED

I too have this noise, and until Ford itself changes its mind, you will probably will not find a dealer to attempt a repair. I have also heard the noise in alot of other F-150's, some people hear it and others don't or choose to ignore it.

Later