that your TCC cluitch works properly. If your truck is overwise working normal I would say the likely explanation is age/wear like the pump isnt moving the same volume fluid it once did. Can you confirm youre checking the fluid level properly by telling me how you inspect the dipstick?
And be thorough

 

another thing, when traveling at 50mph, drop it into 3rd by using the OD on/off button on the shifter. That should promptly and quickly shift into 3rd, then driving that for 5 seconds or so, without changing anything else (Throttle angle, brakes etc) hit the switch again. does it instantly and quickly downshift? try this warm and cold , you should notice that its sluggish when its cold but should be quick at temp. SDoes your truck have the factory trans cooler in the radiator / in front of the condensor or just the one in the radiator, or, was it replaced by someone with an aftermarket one.

 

When checking trans fluid, I have the truck warmed up (say after a trip) on a level surface, in park, engine running. I yank the dipstick, wipe it, stick it back in, pull it out and inspect. Fluid is red, doesn't smell burnt, and is within the normal range on the dipstick.

I have done this before. At 50MPH, turning OFF OD shifts into 3rd immediately. Shift feels perfectly normal. Upon turning ON OD, the truck will immediately shift back to overdrive. That shift also feels normal enough.

In terms of trans coolers, I've got a fairly large one in front of the condenser. Not sure if it is factory or has been replaced before. It certainly doesn't look aftermarket.

 

After driving the truck a bit this weekend, I have an uneducated suspicion as to what might be happening. So I've heard that the torque converter will stay unlocked until the trans warms up a bit. I noticed that for the first few shift cycles everything feels OK. Now, when the truck gets warmer then the little hiccup happens. I'm not entirely sure how the E4OD specifically is designed to operate, but I assume it unlocks and re-locks the TC during each shift. What I SUSPECT may be happening is that from 3rd to OD, the TC is staying unlocked maybe 1/2 a second longer than it used to. It feels to me like I can feel the distinct shift from 3rd to OD and then the TC lockup. Mind you, this all happens within a second and a half, I'd say.

Also worth noting: at anything above 1/4 throttle it feels much more normal. Like I said, when I'm driving unloaded I really stay out of the gas if I can help it.

 

I'll probably start my own thread but I sort of have the same thing going on with a 4r100. Started with one laggy shift from 3 to 4. Now its loss of 4 altogether but it was intermittant loss for a couple of trips. I have started with driving while watching the solenoid status on Forscan. At least that shows you what the computer is trying to tell the solenoids to do while running through the gears. Whether the solenoids are following orders or not might be another question though.

My impression is that the e4od is like the 4r100 and that od is the last clutch to engage in sequence so a marginal line pressure can fail to clamp the od piston hard enough to grab 4th gear. (assuming the clutch plates are good etc)

 

not a bad thought, yes the E4OD unlocks during shifts but the tcc doesnt lock, iirc, under a certain speed, so its only gonna be seen in those upper gears. Also also, if you have a trans cooler thats fairly large, what ambient temps are you looking at? If its cold out maybe your trans is running cool. my radiator end tank cooler is bypassed (failed at the fitting) and i have a cooler in front too but I put ti there. It gets cold herer, if I dont block airflow it wont ever get to 150 let alone 175 etc. Those cold temps could promote larger line presure. I forgot what year you have but Id like to know your trans temps and what the EPC voltages are. I get to see mine on the obd2 data stream as I have a 96 f150, but anything but a 96+ california f250 shouldnt have obd2. You would need something that interfaces eec-iv stuff.

BUT in the spirit of KISS, you have checked your fluid wrong. first. you need to make sure your trans is warm enough from your drive. without knowing temp, you should operate in a way that gets the temp up, drive around town or at high load for a bit longer than your other drive. When in park after drive, shift to each gear range for 10-20 seconds each, before going back to park, pull dipstick and wipe clean, insert dipstick. Wait 5 seconds Pull dipstick and carefully examine level, use a white paper towel if needed to sponge off the dipstick so the spot it reaches is more obvious. I have a hard time seeing frresh atf on the metal dipstick in mine because the dipstick is a darker shade of metal. Just the waiting 5 seconds is huge becaue the dipstick will have fluid touching the walls yet from the first pull out that can make it seem much higher than it is. in my case it was the difference between overfull and like 1.5 pints under the cross hatch

 

I see my Forscan suggestion was not applicable. I have a F-SD like that but its a year newer with OBD2. I'll pay closer attention next time I drive it but usually I can feel 4 shifts. I thought that the 3rd shift is the converter locking in 3rd gear(pretty soft with only slight drop in rpm) followed pretty quickly by a shift into OD (a firmer shift with more drop in rpm). Perhaps my impression is the opposite of what actually happens inside there.

 

easy way to find out is to hold the brake lightly while doing that speed . when you are confident you are in od then let off

 

You know, that's a fair point. The problem only seemed to start this winter. I was seeing temps in the 20s, 30s, and occasionally the 40s. I'd bet with the robust cooling system on this F-450 the trans wasn't getting up past 150.

I'll check it this way and let y'all know what I see.

 

Guys, I bet y'all thought this was mothballed. Well, have no fear, I finally got off my butt and did the trans service. Dropped the pan and did a filter change. The fluid looked good and red, and there was just a small amount of clutch material paste at the bottom around the magnet.

Unfortunately, whoever put in the reman trans used a newer torque converter without the drain bolt, so I wasn't able to drain the TC. Also, there was a bolt that I assume goes to the valve body that was loose and would have hit the bottom of the pan if not for the filter blocking it. I got it threaded back in and tightened.

Put in about 7 qts of Mercon V, fired up the truck and drove around the block to get it warm. Came back, pulled the stick, ran the truck through all the gears and dipped it again. Level was a bit low, so I added another 1/2 quart and that got us about halfway on the crosshatch mark.

Probably just the placebo effect but it seemed like the truck drove a bit better. That wonky shift is still there but I think we're gonna live and let live for now.

 

That wonky shift is called "shift flare" between your 3 to 4 shift. They call it this, due to the "flaring up of revs" if you will, before the shift. You don't want any, because what's going is, the clutch discs are slipping a bit before fully engaging. Some clutch material will be found on the magnet between fluid changes, but every time it flare shifts, it's contributing more and wearing them out. From the factory, they make them do this for driver comfort, so you don't feel the shifts. The valve body valves and springs can have a bit of ware on them too and these springs wont be changed during a reman.....unless they install shift kits, which I'm sure wasn't done by the sound of your description. You can address issues like these by installing shift kits like these:

https://www.ford-trucks.com/forums/1...nd-towing.html


They're not just what the cool kids are doing. They truly do resolve issues like these and help you trans last longer by removing these shift flares.

Awesome truck by the way! Love these era F450's. I've got one w/ the longer wheelbase + a custom 3' stretch w/ the diesel.

 

Very glad to see you chime in on this one! Yep, definitely feels like a "flare". Wish I'd have known about the TransGo kit when I did my last service, I might've looked into one of them while I had the trans apart.

Now that I know it's a "normal" (albeit dumb) function I'm a little less concerned. When I did the trans service, everything looked fine, just a small amount of clutch material in the pan. The truck does have an alleged reman transmission. Although, the more concerning thing is why was the trans remanned at 80K miles........ Who knows. I did replace the burned-out 3rd brake light, maybe that's what they were chasing with a brand new trans.