4r70 skipping second
Thread Starter
|
New User
Joined: May 2011
Posts: 15
Likes: 0
4r70 skipping second
I have a 97 F150 4.6 4x4. Many, many miles on this truck. Issues I am having are as follows.
1) Long delay going into drive. From reverse or neutral it takes an abnormally long time to engage drive. When it does finally engage it does so softly, not abruptly like my 4r100 expedition or my 4r70 going into reverse. Have not noticed any slipping under hard or light acceleration though.
2) The trans seem to skip second under light-medium acceleration. It will shift to second and immediately shift to third, or just skip second all together. I can always force it into 2nd with the lever and doesn't slip, but does seem to take a while to engage.
3) POSSIBLY shift flare. mostly between 1-2 and 3-o/d
None of these issues happen 100% of the time, but regularly enough for me to notice. Fluid is at proper level. I have all four gears and reverse.
Any ideas?
1) Long delay going into drive. From reverse or neutral it takes an abnormally long time to engage drive. When it does finally engage it does so softly, not abruptly like my 4r100 expedition or my 4r70 going into reverse. Have not noticed any slipping under hard or light acceleration though.
2) The trans seem to skip second under light-medium acceleration. It will shift to second and immediately shift to third, or just skip second all together. I can always force it into 2nd with the lever and doesn't slip, but does seem to take a while to engage.
3) POSSIBLY shift flare. mostly between 1-2 and 3-o/d
None of these issues happen 100% of the time, but regularly enough for me to notice. Fluid is at proper level. I have all four gears and reverse.
Any ideas?
Frmr Ford Trans Engr
Joined: Aug 1999
Posts: 24,734
Likes: 2,663
From: SE Florida
Check for codes. If that doesn't show the problem then you'll need a high end scan tool that can look at live data. You need to see if the trans is shifting when the PCM tells it to. We need to know if the problem is in the electronics or the trans. If the electronics tells it to shift and it doesn't do it for several seconds, then it is a trans problem. If the PCM is telling it to skip second it is probably an electronics problem.
Thread Starter
|
New User
Joined: May 2011
Posts: 15
Likes: 0
No trans codes and the O/D light is not flashing. I used a crappy scanner but it did show the computer commanding 3rd when it shifted. Maybe it's just the way it was designed to shift but it seems strange
Thread
Thread Starter
Forum
Replies
Last Post
kc2006
1999 - 2003 7.3L Power Stroke Diesel
4
Apr 10, 2011 10:58 AM
93ExplorerXLT
Clutch, Transmission, Differential, Axle & Transfer Case
2
Jan 16, 2002 10:04 AM
