4R70W Shifting problems
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Junior Member
Joined: Aug 2006
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4R70W Shifting problems
I found this forum and hope someone can help even though my Ford is a van.
Truck info : 2000 E-250 5.4L 113k miles 4R70W transmission , fluid and filter changed 3 times since new. I work on marine and industrial diesel engines and generators , but have little experience on automotive trasmissions. I felt it would be better not to try to "do it myself" , even though I am mechanically skilled.
I have had this van since new and it's been very good to me.
Recently , I noticed it start to have shifting problems from 2-3. It would not shift into 3rd at the right RPM , continuing upwards in RPM. Instead ,it would leave 2nd into neutral. I would immediately let off on the throttle , and it usually would go into 3rd , then shift to OD normally. This condition was worse when the vehicle was first driven , becoming less as the vehicle warmed up . Because I was under a time constraint at work , I had to drive it this way for 3 days , but I was easy on it.
I brought it in to a local transmission guy who asked me to drive it one more day that way (he was slammed with work as well). The next morning , I started out , but it would not even shift into 3rd at all , and now the OD light was blinking indicating a code .. I brought it in , they pulled the "code" (2-3 shift error *duh*) , and they dropped the pan .. the fluid was still clean and not discolored , very few particles on the magnet. They decided to change the solenoid pack with a known good used one and a filter and see if it made any difference. It did not , so they then dropped the valve body and found a broken spring and a sticking piston. They replaced the parts and test drove it . It now shifted fine from 2-3 and then to OD , but now , after it warms up , it will slip out of overdrive into 3rd. If I hit the OD cancel , it will stay in 3rd all day. What is odd is that I got on the interstate right away after it had a chance to cool down one time and it was fine for quite a long way (30 miles) without slipping out of OD . They said it was possible that driving it with the 2-3 shift error could damage the OD band , which would mean overhaul . I didn't buy that , because I never had an issue with slipping before this , just shifting into neutral. I was told the servo that controls the OD , or the solenoid that controls the servo could be the problem now. My thinking is maybe a piece of something could have gotten in to servo cutting a seal or something.
By disturbing the valve body , could they have screwed something up? They seemed reluctant to do anything else than try to sell a rebuild.
Is this servo accessable outside the case of the transmission?
If someone has any ideas I'd like to hear them. I hope I described the problem well enough for someone with experience to help. Thanks !
Truck info : 2000 E-250 5.4L 113k miles 4R70W transmission , fluid and filter changed 3 times since new. I work on marine and industrial diesel engines and generators , but have little experience on automotive trasmissions. I felt it would be better not to try to "do it myself" , even though I am mechanically skilled.
I have had this van since new and it's been very good to me.
Recently , I noticed it start to have shifting problems from 2-3. It would not shift into 3rd at the right RPM , continuing upwards in RPM. Instead ,it would leave 2nd into neutral. I would immediately let off on the throttle , and it usually would go into 3rd , then shift to OD normally. This condition was worse when the vehicle was first driven , becoming less as the vehicle warmed up . Because I was under a time constraint at work , I had to drive it this way for 3 days , but I was easy on it.
I brought it in to a local transmission guy who asked me to drive it one more day that way (he was slammed with work as well). The next morning , I started out , but it would not even shift into 3rd at all , and now the OD light was blinking indicating a code .. I brought it in , they pulled the "code" (2-3 shift error *duh*) , and they dropped the pan .. the fluid was still clean and not discolored , very few particles on the magnet. They decided to change the solenoid pack with a known good used one and a filter and see if it made any difference. It did not , so they then dropped the valve body and found a broken spring and a sticking piston. They replaced the parts and test drove it . It now shifted fine from 2-3 and then to OD , but now , after it warms up , it will slip out of overdrive into 3rd. If I hit the OD cancel , it will stay in 3rd all day. What is odd is that I got on the interstate right away after it had a chance to cool down one time and it was fine for quite a long way (30 miles) without slipping out of OD . They said it was possible that driving it with the 2-3 shift error could damage the OD band , which would mean overhaul . I didn't buy that , because I never had an issue with slipping before this , just shifting into neutral. I was told the servo that controls the OD , or the solenoid that controls the servo could be the problem now. My thinking is maybe a piece of something could have gotten in to servo cutting a seal or something.
By disturbing the valve body , could they have screwed something up? They seemed reluctant to do anything else than try to sell a rebuild.
Is this servo accessable outside the case of the transmission?
If someone has any ideas I'd like to hear them. I hope I described the problem well enough for someone with experience to help. Thanks !
Junior Member
Joined: Feb 2006
Posts: 9
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From: Michigan
Hey, I have a friend in which that same exact thing happened. We pulled the tranny and replaced it with a used one that had 30,000 miles on it. It is running fine now and we are not sure what caused it but we might tear it apart and diagnos it.
Senior Member
Joined: Feb 2005
Posts: 154
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From: North Carolina
If a total rebuild is out of the question (for whatever reason) and you say it works normally in "cool" conditions, why not try a more robust tranny fluid cooler? That is, assuming you are still only using the stock tranny cooler. This may not correct the problem, but it may make conditions such that the fluid stays cool enough so the OD works.
Just something to think about.
NCC
Just something to think about.
NCC
Senior Member
Joined: Jul 2004
Posts: 1,380
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From: cincinnati
The 2-3 retainer is very easy to get out of place when doint the valvebody. it will cause direct pressure to be exhausted the wrong way and loss of 3rd and 4th gears in extreme situations.
Alan
Alan
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Originally Posted by dirtyd0g
The 2-3 retainer is very easy to get out of place when doint the valvebody. it will cause direct pressure to be exhausted the wrong way and loss of 3rd and 4th gears in extreme situations.
Alan
Alan
It shifts fine into third at all times now , and when the unit is cold , it will go into OD and lockup fine .. but after about 15 miles of city driving is when it acts up. If I get on the highway when it is cold , it will go for many miles without slipping from OD to third.
There was no problems with 3rd and OD (when it would go into 3rd) before this whole thing occurred , and they are trying to tell me the OD band might be bad now. I dont buy that. My thinking is there's a problem with the pressure being directed to the right place when hot. I could be wrong , but my gut says no.
Also , Is the solenoid and servo for OD accessible from outside the case of the transmission? thanks