Ford 4R70W / 4R75W Transmission Question

[Fred W]

Hey collective,

Let me preface this question with he observation that: I sure wish the Ford Truck community was even in the same intelligence zip code as this place for technical knowledge.

I've spent the better part of a 1/2 day Google searching and forum lurking trying to find a credible lead on my "little problem". So now I'll turn to this incredibly diverse and intelligent collective and see if any of you have been down this bumpy road before.

I have a 2004 Ford F150 pickup with the small (4.6L) V8. This is the new body style not the "Heritage". For some time now I have had an alarming (but not extremely so) transmission issue where if I have been coasting (or decelerating) for a while and then step on the gas, sometimes (but not always) I get a short period of "slip" before something engages with a slam, and then we are back in business. I never get any slippage running down the road. And I have somewhat modified my behavior such that I try not to let off the gas, and then re-accelerate hard, but it still happens now an then.

I get a feeling that this is either a fluid flow issue into the torque converter, which may be resolved with a good flush and filter change (hopeful here), or if that is not the culprit it may be that the control unit is not re-engaging the TC soon enough.

In all other regards my truck is in great running condition. And I'd really like to keep this thing for a good long time as I enter into retirement not too far off. But I do not cherish the idea of dishing out thousands of bux to transmission shops for their often shady work only to have the problem continue.

I'd jump in and do the fluid exchange and filter replace if I had the least bit of confidence that would help. That seems to be the placebo thrown out by the automotive gearheads at every opportunity. But the transmission works flawlessly other than immediately after coasting, which makes me awfully suspicious that it is a control issue rather than a a mechanical one.

 

[rushes]

If I remember correctly, my 04 had a 'shudder' going in to overdrive that was cured by an additive.(By the dealer, under warranty)

I'd try the flush and new filter.

 

[Fred W]

Thanks Russ.

I turned up a number of similar "shudder" complaints, which seem common, and I think that is due to overheated and degraded fluid.

But I'm not positive that describes anything even similar to what I gots. I'll probably go that route just because it's cheaper, can't hurt (except my wallet) and I can do it all myself, making a mess in the garage. But I'd welcome any more input or on experiences others have had.

 

[airboss]

Short answer Idontknow.

But if turns out to be serious internal issues, then I would price a rebuilt transmission. Sometimes they are cheaper with one or two year warranties versus paying someone for parts and labour.

 

[infrared]

Fred,

Let's make sure that you are at the right end of the problem, first. Check the fluid in the rear differential, first, for the correct level and possible contamination.

I do not know that specific transmission, but if it has a vacuum modulator, pull off the vacuum line at the engine, and apply suction. Once there is a vacuum in the line, the vacuum should hold, without any air leaking in. A big automotive syringe (or maybe even a turkey baster) can do this test. If the line or vacuum modulator leaks, fix that first. A vacuum modulator is usually a very easy fix.

Good hunting!

Infrared

 

[08FJR4ME]

My 2007 edge seems to have the same symptoms. It ocasionally will clunk or slam into gear. I have been ignoring it and it seems to work fine otherwise. We had the tranny fluid changed about 7 months ago and it didn't get rid of it. Totally different setups I am sure but same symptoms. That's the least of my problems right now with the edge.

I also have what they call the PTU (power transfer unit) In fords infinite wisdom suposedly the oil is lifetime and not serviceable. So eventually many a Edge owners oil in the PTU overheats vents out and whats left turns to paste. I believe I have caught it before the seals have let go. Last weekend I managed to add some oil to it. (75-140 synth) The unit is still overheating. so tomorrows attempt will be to add a drain plug in the bottom of the casting to try and drain whats left if possible and refill again. This may take a few refills to flush out the crap inside. It is way to much work for me to pull this unit out. Cost of the rapair is between 2 to 4 grand to fix. Around town for short runs it is fine but any longer rides or highway is asking for trouble at this time. Cost to replace vehicle 40K. Momma hasn't been working for a while so that option is out.

4 wheel vehicles suck, ride bikes

Dave

 

[FJRay]

I'm not sure but I believe vacuum modulators are long gone and shift points are controlled by throttle position and electronics. I would suspect the TC and or the mechanism that controls the lock up. I think doing your own service is a good idea but in this case the machine they use to flush may be the ticket to make sure the TC is cleaned out. I don't know if yours even has a drain on it so you would only be changing part of the fluid. I would find a reputable trans shop and has it flushed good and they should be able to run any diagnostics and a pressure test. pressures are critical in modern automatics.

 

[FJRay]

My 2007 edge seems to have the same symptoms. It ocasionally will clunk or slam into gear. I have been ignoring it and it seems to work fine otherwise. We had the tranny fluid changed about 7 months ago and it didn't get rid of it. Totally different setups I am sure but same symptoms. That's the least of my problems right now with the edge.I also have what they call the PTU (power transfer unit) In fords infinite wisdom suposedly the oil is lifetime and not serviceable. So eventually many a Edge owners oil in the PTU overheats vents out and whats left turns to paste. I believe I have caught it before the seals have let go. Last weekend I managed to add some oil to it. (75-140 synth) The unit is still overheating. so tomorrows attempt will be to add a drain plug in the bottom of the casting to try and drain whats left if possible and refill again. This may take a few refills to flush out the crap inside. It is way to much work for me to pull this unit out. Cost of the rapair is between 2 to 4 grand to fix. Around town for short runs it is fine but any longer rides or highway is asking for trouble at this time.

4 wheel vehicles suck, ride bikes

Dave

exactly why I got rid of my 07 Edge. trans was changed at 72 k and the Ptu **** the bed shortly after that.

 

[Just Krusen]

I drive a '05 work truck. I had the slamming trans issue at around 50,000 miles. It got so bad I thought the tranny was shot. Took it to a trusted transmission shop for a look. After some testing he called the next day and said the truck was done. It seems the truck had a slight miss in the engine that I never felt but the computer picked up causing the torque converter to drop out and re-engage with a bang. New spark plugs and wires fixed it.

40,000 miles later something broke in the trans. I pulled into work ok but when I went to leave I had no forward gears or movement of any kind. Shop showed me the broken part but I don't remember the correct name. I still believe it had something to do with the problem at 50,000.

 

[BkerChuck]

How many miles are on the truck? Has the fluid ever been changed? What does the fluid look and smell like? ATI should be a reddish pink color when in good shape. As it wears it gets darker and begins to take on a burnt smell. I have an 03 with the same drivetrain. I change fluid every 30k miles. I don't drive it that much but do some light towing with it.

 

[Fred W]

Thanks much for the replies.

I have not inspected the rear diff as I could not see how that would be related to the symptoms. What it feels like is that the TC is slipping only during coasting, and then the re-locking is delayed, so when it does re-engage it is at a slightly higher than normal rpm, and the engagements is abrupt. At all other times, including during heavy acceleration runs, it runs and shifts perfectly. It doesn't even do this all the time, just sometimes, and I cannot reproduce it reliably. Even if it continued as is, I don't think it would be a huge problem, but I don' t think ignoring it is the right course of action either as it is likely to become worse with time.

The fluid is red (not very dark), smells like ATF (not burnt) and level is correct. Truck has > 110k miles on it now, bought used, and I have no maintenance records from prior owners

I've read that I can do a total fluid exchange at home using gallons of Mercon V and disconnecting the ATF cooler lines. But I'm tempted to just bring it to a shop that has one of the fluid exchange units and have them do the fluid and filter to avoid the mess. It certainly can't hurt anything except my wallet.

Also, from what I have read, FJRay is correct that my trans is electronically controlled (not vacuum).

BTW - One of the reasons I titled the thread 4R70W / 4R75W is I can't even reliable determine which it is. I have a Transmission code "A" on the door pillar sticker, but I can't find a reliable online reference as to what that code indicates.

 

[bigjohnsd]

https://www.ford-trucks.com/forums/vindecoder.php

The above link will take your VIN and reproduce your original window sticker which MAY identify your transmission for you.

Good luck.

 

[Fred W]

Thanks, John. Yeah, I had found that link a while ago. It gives lots of good info. Unfortunately, the installed transmission is not one of them.

I can find lots of door jamb sticker decoders on-line too. Most seem to be cut and pastes of each other. And none list what a trans code "A" is/was.

 

[08FJR4ME]

My 2007 edge seems to have the same symptoms. It ocasionally will clunk or slam into gear. I have been ignoring it and it seems to work fine otherwise. We had the tranny fluid changed about 7 months ago and it didn't get rid of it. Totally different setups I am sure but same symptoms. That's the least of my problems right now with the edge.I also have what they call the PTU (power transfer unit) In fords infinite wisdom suposedly the oil is lifetime and not serviceable. So eventually many a Edge owners oil in the PTU overheats vents out and whats left turns to paste. I believe I have caught it before the seals have let go. Last weekend I managed to add some oil to it. (75-140 synth) The unit is still overheating. so tomorrows attempt will be to add a drain plug in the bottom of the casting to try and drain whats left if possible and refill again. This may take a few refills to flush out the crap inside. It is way to much work for me to pull this unit out. Cost of the rapair is between 2 to 4 grand to fix. Around town for short runs it is fine but any longer rides or highway is asking for trouble at this time.

4 wheel vehicles suck, ride bikes

Dave

exactly why I got rid of my 07 Edge. trans was changed at 72 k and the Ptu **** the bed shortly after that.

As a sidenote I have over 101,000 miles on the edge and all trouble free so far. Well until now anyway. Love the car and its never been damaged and in great shape otherwise.

Dave

 

[Mr Bill]

2004 explorer v8 door pillar code says v

Well that's not in the book

5r55e tranny fluid changed at 110000

Two years ago passing truck on mass pike I thought they were really loud

At next exit my overdrive light started flashing meaning game over for this transmission

Metal bits covered the pan

I shelled out 3k for a rebuilt one even though this jalopy had over 150k miles

My tranny acted up like yours in the week before the explosion

Only happens to 10 % of the 2004 explorers

Good luck!

 

[bigjohnsd]

Is there a tag on the transmission? Most likely under one of my he pan bolts?

 

[Flash9]

Fred, chances are you have a 4r70w, the 4r75w is a slight variation, but for you problem it is irrelevant. As most places would like to sell you a transmission fluid service, I feel this would be a waste of your money at this point. You stated the fluid isn't dark or smelling as if it is burnt, that means chances are the clutches in the transmission are still in good shape. It sound like a possible seal is cut on one of the pistons allowing the fluid pressure to leak down upon coast down, once applying the accelerator again it rebuilds pressure and engages the clutch pack. The correct steps to identify the cause of your failure would be first to perform a self test of the pcm, if no codes are present, the transmission pan would need to be removed to inspect for debris on the magnet in the pan. Depending on what was found in the pan the next step would be to remove the valve body and perform an air check with a test plate, this would help isolate any faulty piston seals. From there you would need to determine if you wanted to spend the $$ on getting the transmission overhauled, or install a reman transmission. Either way make sure the transmission cooler and lines are flushed properly when the transmission is out. Make sure you bring it to a reputable place that will stand behind their work, there are a lot of shady shops out there. just my 2 cents

 

[Fred W]

Thanks Flash. PM headed your way