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Discussion Starter · #1 ·
02 F250 SD CC shortbox 250k miles (built 7/01). This truck is new to me as of July but not my first diesel. Here is the back story on the issue I'm having and sorry for the long post.

I bought a larger trailer in August (7x14 tandem axle with electric brakes- 2k lbs I tow occasionally) and hauled it maybe 50-70 miles from where I bought it outside of Washington, DC to north west of Baltimore where I keep it. When I disconnected and went to drive home I put it in drive (overdrive on) and the rpm's revved up higher than normal before finally moving in 1st gear but when it caught it was smooth. I thought it was strange and noticed it did this only when either hooked up to the trailer or after towing. Basically I had to push the pedal more to finally get going. So when it happened either the first time or the next time I stopped and put it in 1st and hit the pedal. Truck responded immediately when I hit the pedal and started moving. I was a little concerned initially because I had just bought this truck (maybe 238k miles, originally from WI and I'm in MD; bought it from a wholesale dealer in Chicago), but it seemed to not be consistent.

At the end of August I towed the same trailer plus maybe 1500 lbs of cargo across the country to NV and back about 6k miles. Never had a problem and nothing seemed out of the ordinary. Also I don't drive this truck hard most of the time I stay at 2k rpm or below. In the past month I've noticed that when in drive and starting from a stop this problem is happening more often and with out having towed anything. So I've tried putting it in 1st then 2nd then D and it was/is shifting fine. Recently in the last week or so it's seems to still shift fine but in D I have to give it more on the pedal and rev the rpm's up more to get power when starting from a stop or 1st. It's slower from a stop and doesn't feel like I have any power. In the past few days I felt a little shudder shifting between 1-2 and 2-3. It doesn't happen if I shift manually putting it in 1st -> 15 mph to 2nd -> 27 mph-> D. If I leave it in drive I only really have the lack of power and having to give it more pedal with higher rpms either when it down shifts to 1st or from a stop.

I've been searching the forums and started by checking my atf fluid to make sure I wasn't low. It seemed like I was maybe 3/4 quart low and I put some in to rule it out. Unfortunately I don't know what the back story is on this truck before I bought it but a diesel mechanic looked it over, test drove it and said it looked good which is why I bought it and all the reviews I read on the 7.3 PSD. So maybe two days ago I noticed that the OD light on the OD on/off was flashing. I did not have a code previously. I haven't had the code(s) read yet because I called the local Ford dealer and they want $120 for a diagnostic just to read the codes. That's $120 I can spend towards a better code reader that might read trans codes but I haven't found a suggestion for a code reader that will do that yet; the one I saw was an AE (?) but I don't have a windows based pc only mac.

Today I attempted to change the atf fluid using Mark's write up after going back and forth on whether or not changing the fluid was a good idea. Here's what happened. Drained the pan (8 quarts), pulled the pan to check for any debris, replaced filter, and cleaned pan. Pan was dirty, the magnet was pretty dirty but didn't look excessive. I only found 2 very tiny pieces of what looked like debris but one was in the pan other I found in the drain bucket. The fluid was dark, not black but it definitely looked like the previous owner hadn't changed the trans fluid in a long time.

Could only find 1/2" ID clear tubing in the area so put it on the return line with a hose clamp on tight. But here's the funny part is that I disconnected the return line and it drained another 5 quarts of fluid from what appeared to be the mostly the bypass but some from the return line. I was on relatively level ground. I ran the truck and it was warm. It didn't sit too long before I started and the fluid was still warm, maybe not hot but warm. So that 5 quarts took forever to drain out and I ran the tubing over to the drivers side. Added 7 quarts, started the truck, 5 seconds through each gear and shut off. Well fluid sprayed out the bypass valve, probably not even a pint into the clear tubing and the tubing didn't seal like I thought it would. I had quite a mess and I went through a lot of trouble to try to keep from making a mess. Had a pan underneath the connection but that didn't do squat. At that point I had drained 13 quarts and added 7. I cut my losses and put the return line back on, put in 12 quarts total, ran truck a few miles, topped it off with about one more quart. Obviously I didn't get a full change but more than just draining the pan. It appears the trans is original because I couldn't find a magnefine filter in the line so I'm assuming the TC is original but no guarantee.

Truck is still driving and the TC locks up with no problem. 3rd and OD seem to be perfectly fine it's just shifting 1-2 then 2-3 that I'm now feeling a little shudder or a hard shift. I haven't put the possibility of having to rebuild the trans or replace the TC out of the realm of possibility but could it be the TC shift solenoid, the speed sensor, or the PCM have anything to do with it. I've been searching this site and other over and over trying to find someone else with this problem but really haven't. Before I commit a bunch of money to a big fix I want to make sure that's what it is and not just either replace the TC or rebuild the trans. Plus I don't have a shop that I necessarily know will do the job correctly and as much as I want to rebuild it myself I don't have the time, space, experience to do it at the moment. I could use a suggestion beyond the dealer in the Maryland area. There are a couple truck shops I know of but I'm not really impressed. I know the suggestion will be BTS trans rebuild but does anyone have any other thoughts. I haven't found anyone else with this exact problem. Most of the TC issues have been lock up issues in 3-OD.

Thanks I know that was long and I'm really just contemplating going to the dealer to have them read the code(s) unless someone can suggest a reasonable code reader.
 

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I think you need to work out what is going on with the fluid first. Backflow from the bypass would indicate an obstruction in the cooler circuit. Look for an inline filter right behind the radiator on the passenger side. I'd recommend pulling the lines and see if you can run air through the circuit. Putting it in manual 1 doubles the clamping of one of the drums if I remember right. Maybe your fluid flow issue is affecting the clamping ability in that circuit. Mark will be along shortly to tell me I'm nuts and tell you what's really going on... :winking:

Edit - OK - I'm not nuts. Look at 25:38 on this video:

 

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Discussion Starter · #3 ·
I should also mention that when the trans is cold it doesn't have the shift 1-2, 2-3 delay/more rpm to catch. Only once the trans is up to temp. I don't have an aftermarket trans temp guage. Just the dash and it's never shown that it has been hot. I'm guessing it's not that reliable but the guage has never gone over 1/2. It's cold when starting up. Also just a thought when I was changing the fluid it was in the 60's here in md. Could the trans have cooled down too much and that's why it came out of the bypass line? Also I never drained the TC.
 

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So maybe two days ago I noticed that the OD light on the OD on/off was flashing.
I guarantee that if you continue to drive it with the OD light flashing you WILL need a new transmission.

Today I attempted to change the atf fluid using Mark's write up....

But here's the funny part is that I disconnected the return line and it drained another 5 quarts of fluid from what appeared to be the mostly the bypass but some from the return line. I was on relatively level ground. I ran the truck and it was warm. It didn't sit too long before I started and the fluid was still warm, maybe not hot but warm. So that 5 quarts took forever to drain out and I ran the tubing over to the drivers side.
I don't see where you reinstalled the pan and filter and added the 8 quarts that you previously drained. You didn't just start it up without refilling the pan, did you?

Added 7 quarts, started the truck, 5 seconds through each gear and shut off. Well fluid sprayed out the bypass valve, probably not even a pint into the clear tubing and the tubing didn't seal like I thought it would.
With that many miles I'm sure that the bypass valve needs to be rebuilt. It's easy and cheap. Sonnax makes a kit to do this.

At that point I had drained 13 quarts and added 7.
This seems to be confirmation that after draining the pan you started the engine to pump more fluid out. If that's the case, you can stop working on this trans, it's done.

Running the engine with the pan empty is the surest way to destroy the pump there is. At no point in my instructions does it ever say to do this. It does tell you to shut the engine off as soon as you see air in the clear tubing. I would have to suspect there was A LOT of air in the clear tubing if it took a long time to get five quarts out.

I haven't put the possibility of having to rebuild the trans or replace the TC out of the realm of possibility
I'd move both of those up to the realm of guaranteed now.

but could it be the TC shift solenoid,
What is a TC shift solenoid? Never heard of that.

the speed sensor,
There are several speed sensors. If you had the codes read I could answer this question.

or the PCM have anything to do with it.
Within the realm of possibility, but highly unlikely.

Before I commit a bunch of money to a big fix I want to make sure that's what it is and not just either replace the TC or rebuild the trans.
I think you will need to rebuild the trans AND replace the TC. I would never reinstall a used torque converter on a fresh transmission. That's just asking to do the job over again.

Thanks I know that was long and I'm really just contemplating going to the dealer to have them read the code(s) unless someone can suggest a reasonable code reader.
Any good independent shop should be able to read the codes, and for about half the cost of the dealer.

Just the dash and it's never shown that it has been hot.
That means the trans hasn't been up to 230F.

I'm guessing it's not that reliable but the guage has never gone over 1/2.
I know that the factory gauge is extremely reliable.

Could the trans have cooled down too much and that's why it came out of the bypass line? Also I never drained the TC.
The temperature had nothing to do with it. There is no thermostat anywhere in the 4R100 transmission.

You did partially drain the torque converter. That's where the five quarts that came out when you ran the pump dry came from.
 

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Discussion Starter · #5 ·
After the 5 quarts drained when I disconnected the return line I added 7 quarts per your right up before running the engine. You mention in the write up that if you drain the TC to run the engine for something like 30 seconds and the fluid will fill up the TC rather than pump out. Since I didn't actually take the drain plug off the TC I assumed it was still full and I continued to as the write up directed. When I started the engine I went through all gears R-N-D-2-1 for 5 seconds then shut off which is 25 seconds. I'll have the codes read and go from there.
 

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Discussion Starter · #6 ·
In summary I drained 8 quarts from the pan, disconnected return line in which another 5 quarts then drained out (obviously was the TC draining). Engine was off the entire time. I then added 7 quarts, ran for 25 seconds, and shut off. Maybe 1 quart came out sprayed all over in which I then put another 5 quarts in totalling 12. Trans was full 18 quarts, drained 13, added 7, added 5, which is 12 then 1 more to top off, 13 quarts I drained and replaced. Made sure to run truck and bring it up to temp.
 

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1st, mark is the guru! Listen to him!
I think your original problem was likely a restriction (in line filter under/behind radiator on passenger side?) And or shift selonoids. Had you made this post at your first sign of trouble that may have been all you needed to fix. Now you likely need a lot more! Hate to feed you bad news but I've been on the receiving end of this news before and learned my very expensive lesson the hard way.
 

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Discussion Starter · #8 ·
I understand. I've read about every post I could find on this site and the other diesel sites about the 4R100 trans and he is infamous. I trust what he has to say since he's the expert. I had the code read yesterday and it was a slip between shift 1-2. The forward clutches were going out. I had an independent shop pull the codes and they didn't even charge me. This obviously started a few of months ago here and there and has become a real problem lately. Changing fluid probably accelerated it but I was able to manually shift 1-2, 2-D so I never got stranded. Trans was still working but it was eventually going to leave me stranded at some point having to call for a tow. Since this truck only had one owner before me it looks like he didn't service the fluid for quite some time. I never put it out of the possibility that the trans was going to need to be rebuilt I just didn't want to have it rebuilt if it wasn't necessary and I didn't want to throw parts at it unnecessarily. I'm having it rebuilt and putting a heavy duty TC on it. Thanks for the responses and all the good info. I know a lot more about the trans now.
 
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