Hello everyone, less than two years ago I purchased a 4.0L 2009 4wd ranger with a bad transmission, 132,000 miles, and several other issues that have since been resolved. I pulled the trans out and took it to a local transmission shop to have it rebuilt. I flushed the cooling system, installed a new torque converter, etc. when I put it in. I ran it just about every day and it seemed to shift ok but not like a "new' transmission should. I assumed that it was just how they were. I recently took it on a few hour trip and it seemed to be shifting extra hard. When I was almost home the O/D light started flashing. I checked fluid levels after returning home and by the time I started up again to check for the light it quit flashing. I ran it for about another week until last night when it started flashing again. I limped it 5 minutes back home. This time when I got out of the cab the ATF was boiling out and the trans was slipping so bad that I couldn't even pull it into the garage.

After pulling the pan to confirm that it was toast, I dropped it out of the truck. It has been less than 13,000 miles since the trans was rebuilt. I am now looking for a different trans but I have also been kicking around the idea of rebuilding it myself. The shop that did the rebuild was closed today so I didn't get to call them yet. I have no idea if the trans was changed before I got ahold of the truck. I'm wondering if it is the correct one for the 4.0 (possibly for a 3.0)? The guy that rebuilt it originally said that it must have overheated because there was a lot of discolored parts. The door tag says it should have the "D" trans. I believe it should be the 5R55E. If anyone has any information about identifying this or information about which years I could source a trans from I would appreciate it. There are 18 bolts on the pan.

 

A 2009 4.0l Ranger should have the 2001 Version of the 5R55E, as long as it has a dipstick and tube on passenger side, no dipstick means its a 5R55W, rare in Rangers

The white sticker has 9 L5 P, which indicates 200"9" and "L5" = Ranger, "P" = transmission or axle division
So most likely the original transmission

Casting for case is "F9" model so 1999 which is when the newer 2001 models were being built

2001 is when Rangers got the ISS(intermediate shaft speed) sensor and OSS(output shaft speed) sensor on the outside of the transmissions
ISS sensor is just above shifter and OSS is a little higher and at the rear

Just above the OSS is the Vent, is this where fluid was coming out?
Of its tube

What generates the most heat in a transmission is the torque converter, locking torque converters allowed better MPG but also longer transmission life because of less heat
Slipping clutches and bands(brakes) are next in line to generate heat
Locking torque converters have been around a long long time, its called "the stall speed" of the torque converter, the RPM of the crank causes torque converter to lock internally to transmissions input shaft
Usually that's at about 2,000-2,500rpm, but this is engine specific as far as recommended stall speeds, it has to do with when engine makes best torque/power

In the 1980's transmissions got computer control that could lock the torque converter based on other factors not just engine RPM, also engine load and speed

Form your description I would guess something happened to torque converters lock setup
Could be locking solenoid related or the torque converter itself

You said it didn't "feel right" after the rebuild and the new torque converter
Slipping torque converter wouldn't give you instant throttle response above say 30mph when it should be locked, RPMs would go up faster than speed if it was slipping
The engine and rear wheels(trans) should be locked together when torque converter is locked, same as the clutch on a manual transmission

Also when slowing down, foot off the gas pedal, engine RPMs should stay up matching speed not drop to idle until you are under say 20mph and torque converter is unlocked

There is no way I know of to test if a torque converter is good or bad

You had flashing OD OFF light which means there would be Transmission Codes in computers memory, these can't be read with most OBD2 readers, need one that can read them
I use the BlueDriver and have no complaints, but last I looked its didn't work with Apple phones

The transmissions codes may tell another story as to what failed, could be a valve body issue or solenoid

Yes you can rebuild yourself

 

Thank you for the info Ron! I didn't look closely as to where it was coming from because the whole drivers side of the housing was drenched. The vent had still had the breather hose attached still so I'm assuming that is not where it was coming from. It dumped quite a bit on the ground. That toque converter failure theory is very interesting. I am borrowing a friends 2011 ranger right now so I have something to run. It is essentially the same exact truck except it has less than 20,000 miles on it. The difference is unreal between the two. Mine always seemed to struggle above 40ish mph, meaning there was a significant lag in rpm response on the gauge. When gradually increasing pressure on the petal (most noticeable steep hills) there would be little change in rpms or speed. Then all at once, the rpms would jump. My engine has had rich codes for some time, and I assumed it was lagging because of the rich condition. I checked for codes when the O/D came on the first time with my scanner, apparently it must not read trans codes. Will they stay stored after the battery is disconnected? I unhooked it before I pulling the starter. I may have to get one of those BlueDrivers. The ability to see live data on what the computer is interpreting sounds very useful.

 

A little update... I called the transmission shop that did the rebuild and it is right on the edge of their warranty. I took it down to them and am now waiting to hear back from them right now. On a bit of a side note, does anyone know of a way I could test my catalytic converters for carbon buildup (to see if it is plugged/restrictive)? I had to unbolt them to drop the trans, and I want to see if they were the potential cause for the rich codes. I blew compressed air through them, but I'm not sure how much resistance is supposed to be there. They appear clean and open from the end of the pipe. Thoughts?

 

There should be no resistance
Back pressure in a 4-stroke engine is a MYTH

You can use a Vacuum gauge to test for exhaust restrictions, good tool to have in the box

Idling engine should have 18-21" of vacuum
Raise RPM up to about 2,000-2,500 and hold it steady, vacuum will drop and then come back up and stay steady, slow drop while hold high idle means exhaust is clogged, pressure is building up in exhaust manifold

At idle Blip the throttle(open it wide then let it snap closed), vacuum should drop to 0"-2" then bounce back up to 18"-21", if its slow to return to 18" then clogged exhaust

 

Ok will try that once I get it back together; it might be a little hard to start at the moment lol. Just out of curiosity Ron, do you think the truck would throw any codes if a hole miraculously appeared through the center of the cats? There aren't any emissions tests here...

 

Yes, it would through a P0420 catalyst system efficiency is below the acceptable threshold.

Rear o2 sensor would catch it, it's readings would be to similar to the front o2 sensor

 

I had a horrible thought.
Could a "new torque converter" be bad as so many new parts are today?

 

When I took the trans down I told the guy that the torque converter may have went. He said they do get defective and bad ones more than you'd think.

 

Alright I was doing some searching for a used ranger transmission and I found one for $200 if I go pull it. I talked to the guy at the shop that did the rebuild the first time, and he said that he never smelled one burnt as bad as long as he has been there (7yrs). After a week and a half they have not even pulled it apart yet, and I am getting a bit impatient with the whole situation. The used trans I am looking at has 83,000 on it and is out of an 2006. The front of the truck is smashed in some which is why it is up for grabs. From what I understand any 4.0 4x4 transmissions from 01'-09' should bolt right up to mine right? I wanted to double check before I go through the trouble of picking it up.

 

Yes, as long as it has a Dipstick its a 5R55E trans, so 2001-2011 4.0l 4x4 5R55E trans will work in your 2009 4.0l 4x4

5R55W won't work, they have no Dipstick, these were used on Explorer 4.0l 4x4s mostly, some have said Rangers as well but never seen that myself

 

Update on the truck... I picked up the 06 trans and had mine "rebuilt." The guy said that all the disks inside it looked like the day he put them in, the fluid was just burnt very bad. Basically they took it apart, cleaned it, changed the seals, changed one sensor, and gave us a new torque. If the torque is what failed I think I'll be alright, but I still don't have much faith in it (which is why I picked up the spare). I got it back together today, and it seems to drive and shift fine when up to speed. Idle is rough and it makes a whining noise that sounds similar to tire noise while driving. The idle problem gets worse when the truck is put into gear and it shakes abnormally. The whining noise is not the tires because it never did it before and I am running the same tires. I did do several things to it while I was waiting for the transmission which makes it hard to pinpoint what is causing it: new O2s, new plugs + wires + coil, converted the intake box back to stock (had an aftermarket K and N pipe on it), pulled my front diff out to fix the leaky cover, and cleaned the throttle body. I did not check the gaps on the plugs with a gauge but did pull each plug wire off individually, so none of them are missing. I borrowed a friend's code reader with live data; no codes at all. I took a picture of my trucks rpm graph compared to a 2011 4.0 that is fine so yous can see the difference in rpms at idle. The 2011 is just a little higher measurement because it was not warmed up yet, but makes it easy to see where my truck should be. Any ideas on what might be causing the this stuff? I don't want to run it much if there is something wrong and end up having to use my backup trans.

Mine:

The 2011:

 

Yes, burnt fluid was most likely torque converter issue, it generates the most heat for transmission fluid even when working correctly

I assume they cleaned out the trans cooler and lines

4.0l Automatic should idle at 750rpms after warm up, even 800rpms in gear, depends on emission standards for that year
After engine is warmed up, unplug the 2 wire connector on IAC Valve, RPMs should drop to 500 or so, engine may even stall, either is good it means no air leaks
If idle doesn't change/drop then you have an air leak somewhere

Rough idle is misfires, so clean spark plugs, also put a can of injector cleaner in the tank, I use Seafoam once a year, can tell a difference, although mines a 1994 4.0l with original injectors, lol
Also new PCV valve every 2 years

4.0l SOHC had a known issue with PCV valve hoses, at the elbows, small cracks on under side

 

Yes I made sure that I flushed the trans lines and cooler out before reinstalling the trans. I will try the IAC valve test tomorrow. I just replaced the plugs so they shouldn't be dirty. I can't remember if I changed the PCV valve before; I know I had it out and looked at it.

 

Tried the IAC test and the truck did what it was supposed to. I pulled all my plugs back out and sure enough cylinder 4's plug gap was almost closed. I'm about 99% sure I dropped it while I was putting them in. They are all spaced at .057 now and it idles perfect. Thanks for the help Ron!

 

Good work

Thanks for the update, and THE FIX

 

Hey folks. Unfortunately I have to bring this thread back to life. My truck has been operating perfect with no issues, running it just about every day since doing the work last mentioned in the thread. I was on my way back to college from being home for thanksgiving and felt the transmission start to slip as I got on the ramp to the interstate. Since I was able to get up to speed, I continued 20 miles with no slippage to get off at my exit, drove a bit more then had to pull over. Essentially lost D and R, still had 1 and 2. Fluid level seemed fine, didn't seem overheated like the failure mentioned above. What is interesting to me is that this appears to be the same failure that occurred before I bought the truck. It then had no D or R but it would go in 1, 2, or if you toggled the OD switch. I didn't confirm if the OD off helped this time and haven't had the chance to read the codes since I've been at school. However, my dad pulled the pan for me, said the fluid looked fine, didn't smell burnt, and no metal chips. My current theory based on this chart is that the sprag that seats in part 40 here flipped or failed. Anyone have thoughts on this or alternative theories? I WILL be taking it apart myself this time to confirm what is wrong with it even if I don't use that transmission. I'm certainly not going back to that transmission shop lol. Anyway, the current plan is to install the other trans I have out of the 2006 with new fluid, a new cooler, an aux temp sensor, and filter. What do you guys think about keeping the same torque converter that was in the 2006? I've heard its best practice to always change them, but it was pulled out of a running and driving truck that had been in a front end collision. Because I have limited time to do the work over Christmas, I'd prefer not to change the torque and just try the spare trans. Although, I'd rather avoid the chance of having a torque failure, at this point the game of musical transmissions isn't really intimidating lol. By the way, the exploded parts diagram below is for an earlier version of the 5r55e, since I was able to get my hands on a copy of that service manual for nothing.

 

Yes, symptoms point at failed sprag(one-way clutch)

The common symptoms is no movement in R or D but manual shift to 1 or 2 will get you moving, using the Coast Clutch, then you can shift into D to stay moving, but no R

OD button just goes to computer, it will then activate OD when above 45MPH as needed if ON, or not activate it if OFF, no effect in the 5R trans for 2nd gear OD use
The 5R is strictly a software change in the computer, the 4R and 5R are exactly the same transmission internally

 

Cool. I'll let you guys know for sure what happened once I pull it apart. Any thoughts on the torque converter? Also, could anyone confirm if the OBD link MX+ will read trans codes and transmission temps? I was going to purchase the bluedriver, but I read that it can't read the ms can, and thus won't read trans temp.

 

The MX+ can do more than Bluedriver, including trans temp in real time

 

Yep, MX+ will read Trans Temp and Trans Gear status, amongst a butch of other things. It's dashboard mode can be configured to display just about any variable live as you drive.
Link below for more info on the OBDLink#MX+ and the OBDLink#EX modules+software.
https://2001fordexplorersporttrac.fa...dDiagnosisPort

 

An update on the truck, was able to pull the trans apart and verify that the sprag rotated both directions, so it was probably the issue. I also mic-d the inner race diameter to see if the trans shop changed it when it was rebuilt, but it only measured about a .0004 in taper from end to end; so likely was changed/not the cause of the flip. I didn't pull all the drums out but the frictions in the coast clutch looked fine. I decided to put the 06 trans in after disassembling it and verifying the condition of its hardware; its frictions and sprag looked ok. Test drove it quite a bit today and it seemed to work pretty good. The only minor thing that I noticed is that the rpms only drop about 250 after shifting. It still shifts pretty smooth so I don't know if its worth even being concerned about, will have to read a bit more about how it actually shifts. I also got the MX+, very pleased with it. Trans temp has been hovering about 155-160 F which seems normal.