Help Master Mechanics...Been following the forums for years but I am lost now on what the problem I have.

Spent hours trying to find out what trans I have. Ford dealer ran the vin and says I have a 4r55e. Ford Ranger Automatic Transmission Identification says I have a 4r44e. Pepboys says I have a 5r55e. Not sure if it identifies it but this is on the trans.. RFXL2P-7006-AB 750Nm. 95GT-7A040-8A.

On to the strange problem. Its been running a little rough and once in a while I will get misfire codes from Cylinder 1&6 . Just started to notice when the car is in OD doing about 60mph it will jerk or serge a little. I thought maybe it was the misfire. If I turn off the OD it does not do it anymore.. Been getting worse last few weeks. Have never had any codes for transmission. Have had a few on O2 sensors error codes.

So I replaced all three O2 sensors and then the new problem started. I drove it once with the new sensors and rand about the same. I turned the car off and when starting and driving again I noticed the motor was much louder and shifted harder in all the gears. Also it started to squeal a little. Once it gets into OD its kind of ok but if push off the OD button is squeals getting back into drive.

So since it got much worse after putting the new O2 sensors I decide to put the old ones back in. Well it switched back to normal and much smoother also the motor was quiet again and shifted the same with light jerking in OD.

Now I put back in each new O2 sensor and drove it before putting the next to see if one sensor was bad. But I put all three and was fine. Then after driving for 20 miles when I was playin with the OD button it got loud again and squealing again. I disconnected the battery for 2 hours to see if it would reset and no luck.

So what do you think? Sticking solenoid? Maybe MAF going bad? I got new oil and filter ready to install and bought a 1/4 drive torque so I can adjust the OD Band. Not sure if I should put a shift kit and change solenoids and valve body gasket.? I would hate to do all this and have the same problem and need a full rebuild.

I will also try disconnecting MAf and see if it drives different. Again no codes using my AutoXray scanner.

Anyone got any ideas? Thanks....
https://www.ranger-forums.com/rf/for...lies/irked.gif

2000 Ford Ranger
V6 3.0 flex fuel
2 WD
Automatic trans
250,000 miles
Only owned it for 20k miles
Fluid level good
No Leaks
Only codes I get is Cylinder 1&6 misfire
Just changed all 3 O2 Sensors
OD light does not flash and works fine.

Casting on trans.
RFXL2P-7006-AB
750Nm. 95GT-7A040-8A

Vin Number
1FTYR14V4YTB11441

 

Update. I tried a new oem MAF and no change. I also adjusted both bands on the transmission. Still have the same problem. The motor is still loud and sounds like it working hard like pulling a trailer up hill. But with the problem switching on and off leads me to think its electronic . Please help... What could I try next?

 

Have you checked your Fan Clutch.
When you first start the engine cold you should hear the "roar" of the fan as the clutch fluid is cold and fan is fully engaged and pulling air, after about 15-30 seconds the "roar" should die down as clutch fluid warms a little and disengages the fan so it is not pulling air.
This Fan "roar" is engine noise, if it is intermittent you can feel it in the engine power, same as turning on A/C compressor is felt, normally the clutch engages so slowly you never notice it, unlike the A/C which is an on/off.
After startup the Fan clutch is engaged and disengaged by Radiator heat, it has a bi-metal spring on the front, next to rad face, as the rad heats up the clutch slowly engages fan, in winter months that may never happen since rad and cold outside air temps can keep engine at operating temp without extra air flow from fan.

Bad fan clutch could also cause belt squealing.

Higher load/RPM engine issues are usually lower fuel pressure or exhaust blockage issues.
Fuel filter is only $10 and if you haven't changed it then I would just because of the 250k miles.
Lower fuel pressure/flow would usually cause Lean codes as computer needs to open injectors longer to maintain 14:1 air:fuel mix
Vacuum gauge can help ID low flow on exhaust, blockage in exhaust can also make for louder engine noise.

Not sure why the issues with new O2 sensors, you do need to reset computer after installing them, or unhook battery for 5 minutes.
It usually takes 5-10 "drive cycles" for computer to relearn new O2 sensor readings


I would go with the VIN identification of the trans you have, 2000(4R44E)/2001(5R44E) were transitions years for the automatics with 3.0l engines.
At 14 years old/250,000 miles the trans could be failing and need a rebuild.

 

Wow RonD you hit the nail on the head, The fan is locked up solid.. I feel stupid for not checking the fan. What weird is 3or 4 times it went from noisy to loud. The squealing mus be the serpentine belt. its strange that it squeals when changing gears.. I can see the metal spring hanging out and the fan is locked solid. Taking it out now. Thanks for the idea. Thats what I love about these forums..

 

Once fan belt is off you should wire brush, sand paper or emory cloth ALL the pulleys, rough up the surface that the belt rides on.
Squealing noise means belt was slipping and this causes glazing on the pulleys, slippery spots, and this will cause more slipping and more glazing, and more.......ect

So even if you put on a new belt it will start to squeal if it gets wet.

Look on the rad support for the direction to turn nut for unscrewing the fan clutch, not sure on the 3.0l but some are reversed, i.e. not lefty loosey, righty tighty, lol.

 

Yes got it off. Its a RH thread. I just replaced a water pump a few months ago and the clutch was good. The bearing came apart in the clutch. I hate coincidences. this had nothing to do with O2 sensors but when putting the old ones back in it ran fine for 20 miles. When I switch OD off the motor revs higher causing the squealing. I was 99% sure it was the trans squealing. Makes sense now. Going to get a fan clutch now. Should be testing today..