I have been trying to solve this issue for months to no avail. My truck has been shifting erratically lately, and it only is becoming worse. When accelerating and about to shift into higher gear, the truck seems to rev high and then instead of smoothly upshifting, sometimes it hard shifts up or worse it seems to stall or down shift and then upshift like it is searching for the right gear. It happens alot more often when i am feathering the gas. When i go full pedal, it shifts somewhat smooth with an occasional hard shift. I should mention that the spedometer jumps around alot but from what i have learned, this year of f150 the spedometer is only mechanically controlled. I have pulled codes key on and running but dont have any related codes. Also should mention to problem is much more dramatic when the vehicle is at operating temp, almost unnoticeable when first driving cold. The E4od transmission is remanufactured from about a year ago and i troubleshooted with the company in which i have replaced the solenoid shift pack and both the accumulator and valve body. Any thoughts? Much appreciated
(i have tested TPS, inspected solenoid wiring harness, replaced MLPS)

 

What happened just before this symptom appeared?How high? Does it have a working tachometer? That's typically the symptom of low fluid, but it can also be due to the wrong fluid. What brand & type is in the trans?True, but there's still a component that converts the mechanical rotation to an electronic signal for the EEC to use to control the transmission.

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So there ARE fault codes? What exactly are they (number & COMPLETE definition for each one)?

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Did you buy the new solenoid pack & valve body, or did they supply the replacements? Why didn't you send the trans back to them for a refund?What was the result of EACH test? What did you inspect the harness for, and what did you find? What (brand/PN/source) did you replace the MLPS with? Why - what test did the previous one fail? Did the replacement pass the same test?

 

Hey Steve,
1. I was getting hard shift from 2 to 3rd gear, then it started searching for gears in all range.
2. Does not have a tachometer. Fluid level is good, new and its mercon 5
3. Id like to know more about the spedometer and EEC. I looked in the transfer case and saw the gear inside there has been worn down. I bought a new spedo gear that goes on end of cable but have not replaced transfer gear. Not sure if this would effect shifting.
4. Code 13- RPM not within self test lower limit. Code 34- EGR valve pressure position sensor voltage above closed limit.
5. They supplied the pack and valve body. They wanted me to try this first, i may get a full transmission replacement but it is such a pain to swap and am wondering if there is a simpler fix. When i replaced the valve body i did get a smoother shift for a while but it crept back and more of the erratic shifting. So it could be a bad replacement valve body, though they say they test them all before sending it.
6. TPS passed for the voltage range, motorcraft. I checked the harness because i have heard of the wires melting from the exhaust. MLPS is motorcraft, i replaced it just because i was getting tired and throwing parts at it(i know i shouldnt do that) I have the older one still on hand. Its the new wiring harness, i bought the truck already with that replaced. Did not seem to make any differnce. Made sure the nuetral position was lined up on the sensor.

 

2. Absolutely. Both the driven (on the VSS/cable) & drive (on the t-case shaft) gears must be in good condition, or the VSS & speedo cable will be jumpy, which will SEVERELY impact the signal going to the EEC for shift management.
4. Those codes don't look right. Did you get them with a scanner? Read that page - they should be 3 digits, and you should only read them with a jumper wire - never a scanner.
5. I'd push for THEM to send someone to diagnose it, or pay for a local shop to diagnose it, AND pay for the 2nd R&R. You paid for a working trans, and you haven't gotten one yet. You should NOT have do all this work on a freshly-rebuilt part.
6. That's not how the TPS is tested - it's much more complex & precise.

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2. Just to understand, the variable speed sensor is not the sensor on the rear differential like it is on models '92 and above? I dont see how a gear drive cable that is linked to a needle spedometer is sending information to the EEC. Is the needle on the dash somehow sending info to the EEC?
4. Based on my Haynes Manual, it says that older models (like mine) flash 2 digits codes unlike 3 digit codes in later models. I use a jumper wire and count the check engine light flashes.
5. Good point
6. I have followed the haynes manual for the guidelines in which the TPS needs to be tested. Also cross referenced with some other forums on this site on how to backprobe the sensor.
So besides just asking for a replacement, do you think that replacing the gear in the transfer case could potentially resolve this issue?

 

2. VSS is Vehicle Speed Signal/Sensor on the transfer case. The sensor on the rear diff is the ABS sensor, and it was not used for transmission management until '92, when the PSOM was added. The VSS has wires just like the ABS, which is how both of them send out their signals to whatever is connected to those wires. Didn't you look at the first diagram I linked above?
4&6. Haynes is good, but it has errors. Read the link I posted about it, which comes from Ford information.
6. Pull the VSS & take pics of the drive gear inside the t-case, which in this diagram WOULD BE behind snap ring #9 on shaft #28, if this showed a pre-'92 t-case.

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2. Great info Steve. I have looked into the diagram and realizing how complicated the E4od is relative to what i thought it was like before. Seems to be receiving loads of information from all over the truck for its shift patterns. Going to take a while to read through all of it. I did take the electric plug out of the speed sensor, which to my knowledge only controls cruise control, and took it for a drive and noticed less hesitation in finding gears but back with a hard shift.
4. Still seing that vehicles before 91 read only a 2 digit code which mine is. Ill look into it more
6. Here are pics inside the transfer case.

You can see shred of yellow plastic from the gear in the back

 

4. Then read the light flashes and find out for sure.
6. Those yellow plastic rings at the back of the well are drive gear teeth that have been worn off. Probably due to the cable lube drying out over the years. Remove the cable from its sheath (it just slides out) and wash it in solvent. If it's crusty or grimy, pull the sheath out of the truck & run solvent through it for a few hours (recirculating). Then apply PTFE grease, and make sure it coats the entire length of the cable inside the sheath.

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For anyone that comes across this thread and has similar issues, it was the Speedo gear in the tailhousing of transfer case. As soon as I replaced it, my trans shifts the smoothest as it ever has.
thank you Steve for some tips as well

 

That gear doesn't just wear out over time - the wear was caused by resistance in the speedo cable. So if you didn't ALSO fix that, the new gear will wear out rapidly.