F150 trans problem
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New User
Joined: Jul 2003
Posts: 1
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F150 trans problem
2002 F150 Crew Cab 31K miles All factory Auto trans.
When slowing down in traffic from 35 or 40mph and accelerating from about 8mph I get a hard clunk, or jaring from what appears to be the tranny trying to upshift?? The clunk is so severe that it feels like someone hit you from the rear.
Dealer has "never heard of this problem" have had it in three times. No luck as of yet. Still under warranty. Any ideas?
When slowing down in traffic from 35 or 40mph and accelerating from about 8mph I get a hard clunk, or jaring from what appears to be the tranny trying to upshift?? The clunk is so severe that it feels like someone hit you from the rear.
Dealer has "never heard of this problem" have had it in three times. No luck as of yet. Still under warranty. Any ideas?
Hotshot
Joined: Aug 2002
Posts: 12,679
Likes: 15
From: BC, Canada
F150 trans problem
Hi Elvis24 and welcome to FTE 
I just checked for TSB's and there isnt anything on it.
Have you taken someone from the dealership (preferably their transmission tech) for a drive to show them what it does?
You might also try asking your question in the transmission forum which is a ways further down on the main forum page.
I just checked for TSB's and there isnt anything on it.
Have you taken someone from the dealership (preferably their transmission tech) for a drive to show them what it does?
You might also try asking your question in the transmission forum which is a ways further down on the main forum page.
Freshman User
Joined: Jun 2003
Posts: 42
Likes: 0
From: Sanford FL
F150 trans problem
I had a toyota (1972) that would do this. darned if it didnt feel like you just got rear ended!
turned out to be a shift controller problem caused by me manually shifting the auto from drive to low and second to drive like it was a manual. I used to romp it around town to play by winding it up real good.
I was told to stop that crap and Toyota readjusted the shift points and controllers. It got smooth again after that.
Not saying this is your problem, but thinking outside the box couldnt hurt. If I had not admitted to shifting the auto manually, I dont know if the techs could have figured it out.
turned out to be a shift controller problem caused by me manually shifting the auto from drive to low and second to drive like it was a manual. I used to romp it around town to play by winding it up real good.
I was told to stop that crap and Toyota readjusted the shift points and controllers. It got smooth again after that.
Not saying this is your problem, but thinking outside the box couldnt hurt. If I had not admitted to shifting the auto manually, I dont know if the techs could have figured it out.
New User
Joined: Jul 2004
Posts: 12
Likes: 0
My '01 SuperCrew has done this since day one. It turns out this is a well known problem (By Ford) and in fact, is caused by two possible maladies. First, there is a spring in the transmission that is supposed to cushion the 2-1 downshift that, believe it or not, just falls out of its proper location. There is a TSB on this one, here is the text from that TSB:
If the 4R70W automatic transmission exhibits a clunk noise during the 2-1 downshift, this may be caused by a planetary support spring that is out of position (01-13-7, July 2001).
Mine was 'fixed' repeatedly and it still sucks. i.e. is not fixed. The easiest way to verify that this is happening to you is to turn off the radio, the blower fan, etc. Find a nice smooth road, and brake firmly from 40 mph or so. Right before you come to a stop, the trans will down shift from 2 to 1 and make the clunk. This is the more minor clunk of the two.
Secondly, there is a known 3-1 downshift clunk that has no fix! This is the violent one you feel when you accelerate firmly away from a low speed. Mine is very easy to reproduce, accelerate from a stop very gently up to 25 mph, let off the throttle and coast down to just below 20 mph, then tip into the throttle and BANG! The other time that it occurs quite often is after I round a corner and begin to accelerate away from it.
What ever happened to Quality being Job 1?
If the 4R70W automatic transmission exhibits a clunk noise during the 2-1 downshift, this may be caused by a planetary support spring that is out of position (01-13-7, July 2001).
Mine was 'fixed' repeatedly and it still sucks. i.e. is not fixed. The easiest way to verify that this is happening to you is to turn off the radio, the blower fan, etc. Find a nice smooth road, and brake firmly from 40 mph or so. Right before you come to a stop, the trans will down shift from 2 to 1 and make the clunk. This is the more minor clunk of the two.
Secondly, there is a known 3-1 downshift clunk that has no fix! This is the violent one you feel when you accelerate firmly away from a low speed. Mine is very easy to reproduce, accelerate from a stop very gently up to 25 mph, let off the throttle and coast down to just below 20 mph, then tip into the throttle and BANG! The other time that it occurs quite often is after I round a corner and begin to accelerate away from it.
What ever happened to Quality being Job 1?
