5R55W Issues..... 2003 XLT/NBX 4.0 SOHC.

[Swinson1974]

I changed the trans filter today and the fluid. It was a pain in the butt. It fills from the bottom. It calls for 4 QTs and fill with 5th until it runs back out of the whole while the truck is idling at normal temp.

I removed a little less than a gallon by letting the drain run then dropping the whole pan and poured it into fluid pan. I figured it must have been low.

I then added two qts to the pan so I'd have less to pump into it afterward (yes I cleaned out everything first.) and then replaced the filter and bolted it back up. I started the car and let it heat to normal temp.

I then pumped two more qts in and removed the hose, nothing was running out. I added the 5th qt and once the fluid was running out I recapped it once the drip slowed down.

PROBLEM... Now when I drive it, it revs in reverse and drive and then catches the gear and goes. It feels like a neutral drop we used to do when we were young and dumb. Once it's driving it's fine and does all it should. I stop at a light or a stop sign and sometimes it acts normal, sometimes it does the neutral drop. When it does the neutral drop it's only after I feel something disengage while I have the brake pedal pressed. I actually felt it disengage, then reengage, then disengage, then reengage once and it moved normal when I hit the gas.

I'm lost. It almost feels like maybe not enough fluid but I don't want to add more and over fill it.

I used (4) Lucas Auto trans fluid and (1) qt of Lucas trans anti slip.

Can anyone offer any help or ideas please?

 

[Cowens726]

Was your rig level when you did this? I ask because when I did this for my 2005 a couple years ago and the directions I followed specifically advised that the rig/transmission was level. My driveway has a decent slope so I ran the back tires up ramps until the tranny oil pan was level. I would think if the transmission oil pan was tilted back towards the drain plug, you would not be able to get the correct amount of oil in the trans. I don't recall how many qts. of oil I added but I followed the same procedure as you and haven't had an issue since. Actually planning on doing it again next oil change just to be on the safe side 150,000 miles and plan on many more. Not sure about the oil that you used I just used straight up Mercon V or whatever it is that is recommended but it definitely sounds like you are low on oil.

 

[Swinson1974]

I was originally on front ramps to get underneath easy, but I took it off the ramps when I started it to let it run to normal temp then check. I knew that would be be an issue just like you said. I've learned the hardway in the past on my older expos. I'm not positive if anyone ever changed it before, it's at 180k. There was a cool reusable gasket on it, so it's probably (thankfully) something that has been done before. I've gotten them at 150k and they haven't even changed the spark plugs. It was commented on the Facebook page for Serious Explorations where I posted also that I may not have put the tranny through the motions so all the fluid was up in the transmission. I'm picking up another QT this morning to check it again, I drove it for a half hour last night in all gears so hoping it fixes it. It reminded me of driving one of my 1st gens with low fluid, I just wanted to check before I added more and ruined it. TY for the response

 

[02ex4x4]

I'm willing to bet it will clear up I do run the lucus additives but I mix it with the rest of the atf I will be adding to thin it out . If you just poured it in you sucked up straight lucus and the valves in the valve body are sticky. Until it thins itself out it will more than likely have some issues. Check fluid again and drive it let it engage before you hit the gas and keep working it . I bet it will clear up.

 

[Swinson1974]

Yea, I got another quart today and when I went to add more (with it running at temp) the fluid was running out frothy. I'm pretty sure my issue was overfill and not underfill. So now I have to most likely take it to a shop and have them totally change all the fluid, not just the 4-5 qts in the pan. From everything I have read, I may have ruined the fluid and when it is overfilled, it delays the gear shifting and makes it shift hard which was the initial problem. Reverse isn't delayed anymore, but drive still is. Just to be sure tomorrow morning I'm going recheck it because I went and drove it 2-3 miles to make sure the fluid was up in the trans where it needed to be. TY for the response.

 

[Drewmcg]

I really prefer Mercon V (Motorcraft) for these trans's . . . .