Hi i have a 2003 ford ranger 3.0 with 133k miles on it The problem i have is the O/D light keeps flashing but when I take a obd reader to it nothing pops up.
I was told you delete the code and see if it would shift into 4th and 5th and it did, but the code came back on.
I changed the transmission filter and put 4 quarts or transmission oil into it, is that enough or would that be low?
what could be making it flash?

codes came back as p0734 and p0735

thanks for any help.

 

You need to check the transmission dipstick with engine running in PARK to see if you need more or less fluid in the transmission

You would have needed to measure the fluid that drained out to know approximately how much fluid to put back in

A Flashing OD OFF light while driving means the computer has detected an issue with transmission operation, usually there will be a code set in memory but not always
The computer often needs to "see" the same fault a few times before setting a code

P0734 Gear 4 Incorrect ratio
P0735 Gear 5 Incorrect ratio
These codes mean the input shaft speed, intermediate shaft speed, and output shaft speeds didn't match the ratio selected by the computer when it activated the solenoids to change the ratios(gears)

The absence of Solenoid codes means the computer is turning on and off the solenoids and not detecting an electrical fault, but the "gears"(ratios) are not responding

Look at a full code list, here: https://www.therangerstation.com/tec...II_codes.shtml
Transmission codes are in the 700's
You will see all the codes the computer CAN USE
The codes the computer DID NOT USE are as important as the code it did use
That's the way OBD codes work, mechanics look at the code that was used, and THEN all the codes that were not used, or should, to do a diagnoses

Did the old fluid look or smell "burned"?

Do you notice the transmission slipping when shifting "gears"?
Slipping causes the burnt look and smell, and means bands(brakes) and/or clutches are not fully engaging or disengaging

This can be caused by low fluid pressure
When you shift in to Reverse does it instantly engage or is there a delay, delay means low fluid pressure
Drive needs 100psi pressure to engage
Reverse needs 150psi pressure to engage

So lower pressure effects Reverse first

And just FYI, automatic transmission diagnoses is much harder than engine issue diagnoses
Automatics have multiple layers of interdependent systems that engines just don't have
Even transmission shops can only guess at a specific cause of any automatic transmission issue, not a Ford thing, ANY automatic

 

yes the transmission oil did smell burned and when I drained it only 3.5Q came out so I was missing one quart. I put the old fluid make in bc it looked to be good still and add one new quart of the recommended oil.

 

Transmission is slipping
Baby it and save up for a rebuild

Or swap in a used 2001-2008 3.0l 2WD replacement 5R44E transmission, with new torque converter, always
Don't forget to clean out the transmission cooler and lines as well

 

Ya i think im going to swap it. pick and pull sell them for like 150-250 so that would be my best bet plus if anything is wrong with the transmission can just bring it back to them. is it possible to swap it with a Manuel transmission if I get all the parts?

Thanks for all the help.

 

If you have never swapped out an automatic read up on Torque Converter seating it will save you a few THOUSAND DOLLARS

Sure, on the manual swap but its ALOT more work

Need the M5OD-R1(M5R1) transmission from a 2001 to 2008 3.0l 2WD, these are engine specific transmissions
Floor plate and boot for shifter
3.0l Flywheel
Clutch kit with Master
Clutch/brake pedal assembly

2003 3.0l Ranger computer from manual trans factory model, 2wd or 4x4 doesn't matter
Need to get at least ONE WORKING key WITH this new computer, and have the working key cut to match your ignition cylinder or cloned
You will need to do some wiring for Reverse Lights and Safety switch by pass

Optional is a Manual steering column to get rid of the automatic shifter

 

I'm just going to put a automatic transmission. I have a 3.0 ffv so Re the normal 3.0 transmission the same?

 

Yes, same transmission 1995 to 2000 3.0l, and then same transmission 2001 to 2008 3.0l

So 2003 3.0l needs a trans from a 2001-2008 3.0l Ranger or Mazda B3000 and 2WD version

Flex Fuel doesn't matter

 

One more question, If I swap it into a Manual and change the ecu would that affect ffv injectors?

 

It shouldn't if you use a 2001 to 2008 computer, but it would need to be a manual trans flex fuel computer if you wanted to run E85

3.0l. Flex fuel used larger injectors AND a Fuel sensor($650), up to 2000, then Ford changed to mid-size injectors on all 3.0l, and gave the Flex Fuel computer software the ability to add more fuel(E85) if needed, and no fuel Sensor was needed