|Searches ExplorerForum.com Only|
|2017 Explorer||Forums||Elite Membership||Chat||Elite Rides||Reviews||Gallery|
|Explorer & Ranger Transmissions, Transfer Cases, & Differentials Transmissions, Transfer Cases. A4LD, 4R70W, 4R44E, 4R55E, 5R44E, 5R55E, M5OD, BW 1354, Control Trac, GEM, AWD. Ford 8.8", Dana 35|
|04-29-2012, 07:50 PM||#1|
Become an Elite Explorer
Join Date: Apr 2012
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
4R70W Low/Fluctuating Pressure
I have a 69 Bronco with a 96 Explorer 5.0 and 2000 4R70W controlled by the first gen baumannator. I've been using this site to search for misc info about the motor and trans for several years now but I finally have a problem with the trans that I can't figure out and am hoping the knowledgeable folks here might have some ideas.
2000 4x4 4R70W started slipping in 1st mostly when cold. It would take 10-15 seconds sometimes to engage 1st or reverse. I dont think the problem is limited to just 1st and reverse because I have had the problem in other gears just not as often. Once, on a 2 hour drive over the pass in cold weather, it would slip in OD for 2-3 seconds then go back to normal.
I have pulled the valve body and installed a Sonnax main pressure regulator valve. The shop actually installed it. They were supposed to ream it and put in the enlarged valve but they said it wasn't necessary. I was very annoyed that they didn't do what I asked but I trusted their judgment. I did this because the ATSG guide suggested blowing air into the TV/EPC port and if fluid came out the filter intlet, then the main pressure regulator valve is bad. It did. Unfortunately, I did not check it after installing the valve body with the new main pressure valve.
I also replaced the EPC solenoid and used all new valve body gaskets.
I got things back together and the problem seems to be a little better but not fixed by any means. It no longer delays going into 1st or reverse which is interesting. But it still slips when cold mostly in 1st.
I took video with the pressure gauge attached to line pressure. The readings seem really strange and all over the place.
I put some Lucas trans conditioner which seems to keep pressure from dropping down to 10PSI as often but it still slips.
here is the video:
I'd really appreciate any ideas. I don't want to just have it rebuilt without knowing what the problem actually is. Seems like maybe a rubber seal somewhere is leaking until it gets heated up and expands?
here is the Bronco:
|( Join the Elite Explorers )|
Explorer Forum has probably saved you that much already, and will continue to save you money as you learn how to diagnose and fix problems yourself, and learn which modifications really work without having to experiment on your own. Elite Explorer members can change the forum "styles" to eliminate most ads, including the blue underlined links, and no ads on photos. Other benefits include the ability to store 1000 Private Messages, add your own avatar to your posts, upload photo attachments directly to your posts and to our Photo Gallery and more. Join the Elite Explorers today. Your support of the forum is greatly appreciated.
|Suggest this thread to friends:|
|Thread||Thread Starter||Forum||Replies||Last Post|
|OBD-II Diagnostic Trouble Codes (DTCs)||BobWiersema||EEC V||8||03-26-2013 10:22 PM|
|1998 Explorer SOHC Fuel pressure spec||fastkurve||Stock 1995 - 2001 Explorers||25||09-30-2012 08:31 AM|
|Oil pressure low - V8 5.0L||SoNic67||Stock 1995 - 2001 Explorers||28||10-27-2010 05:15 PM|
|Fixing oil pressure gauge||zzb3886||Stock 1995 - 2001 Explorers||0||03-24-2010 11:10 PM|
|5.0 swap? Consider using the 4R70W !!||asp84||Offroad Explorer - Ranger Projects||24||12-14-2002 12:53 AM|