So, this has happened twice now...
Three+ hour drives in 90F+ degree temps, with maybe 2500 lbs of people and gear, pulled a long hill (4-5 min in second gear @ 2,000 - 2,500 rpm) at the very end of trip up to house. Put in park, left to idle with AC on, dumped bikes off of and disconnected trailer, went to move truck in drive, no good. As if the trans was in neutral, could've revved to redline if I wanted to with no noises. It would back up ok, put in 1st, it was a bit slow to move but after a second or two, took right off, 2nd, was 2nd. Back to drive, no good again. Back to 1st, ok, back drive, ok. Then drives fine. No issues before either event, and drove fine after each event. Trans temp never went over 165 on this last trip.

2000 Ex, 7.3 4x, 222,000 miles, 6.0 cooler, remote filter.

I've searched this out a bit, but I don't see how the linkage is a problem as this only happens in the above scenario. There is also a mention of the "feed bolts" above the valve body, but I thought that would be a more consistent problem. I was told that Torque Pro and Forscan Lite should be able to tell me if gear selection is happening or pressures are up, but I must admit, I haven't garnered the patience to fully figure either app out. Torque only shows a couple of PIDs from the vehicle and Forscan only seems to deliver very basic info at best. DO I need to upgrade to Forscan Pro? How do I get either platform to deliver the necessary information?

 

I don't know the answer to your situation, but recommend taking the time to set up FORScan on your laptop or FORScan Lite on your phone, and see if it finds transmission codes. I use it to monitor gear selection and torque converter slip.

How-to thread here:

https://www.ford-trucks.com/forums/1...d-q-and-a.html

 

Sounds similar to what happened when I got a rebuilt trans installed. Backstory…
I got my 2000 7.3 4x4 from an old guy on a farm in northern Indiana. Clean, runs great, little rust and 175,000 miles. I put about 6k on it daily driving and did tons of preventative maintenance before taking a multi-day trip. Drove a day and the 2nd morning hit the smokies, engine started running like crap. I’ll skip that part, but once I finished I had it idling in the driveway till it got up to operating temp and out of nowhere had no 1st gear. Reverse was fine, I could get it to move in L or turning o/d off, but it wouldn’t grab 1st like it should or shift. I went over the linkage and replaced the range switch to no avail. I had it towed to Tennessee’s largest Ford truck dealership that happened to be down the road. When they had a chance to check it out they said it drove fine, “pulls just like a power stroke should.” I explained that I was driving to south Florida and pulling a car back, so I at least wanted them to drop the pan and check the feed bolts. I also mentioned idling till operating temp. They called back at the end of the day saying they duplicated it and I needed a rebuilt. $5k installed with a 3 year warranty sounded ok. It made sense to me that this truck did plenty of towing on a farm, it came with a gooseneck hitch after all…
I’m really curious if your feed bolts are loose. I wonder if they leak enough in some cases when the trans temp is just right. I’ve seen coolant bottles hold at pressure, but **** everything out when they start to cool down.

 

First clue is the remote filter, make sure it's not plugged up. Also check your fluid level.

 

BW... Thank you for that. I will work on this tomorrow since its my day off.

 

Simon, Point taken, the temperature idea sounds reasonable. This just makes me scratch my head though... why only after sitting at idle? Plenty of times I have made a road stop to hit the john or grab food and jump back in and hit the road. Couple of times up at 105-110 degrees. BUT, I would turn the truck off to go inside for 5 to 10 minutes. I have heard that this trans doesn't "pump" through the cooler in park or reverse. More recently though, I came across a thread on FB where everyone stated that if the engine is running, it is pumping.... pressure gauge on remote filter says it is, soooo.....
Looks like I'll have to plan on a transmission service here real soon. Not what I wanted to be doing this month!

 

Z- Good news, all fluid filters changed at the end of May in prepping for this summer's trips. ATF topped off as well! I have also heard (after I installed remote filter kit) that they are a bad idea. Any thoughts on the matter?

 

I'd skip a remote filter, more chance for problems than benefit. But if it's not leaking and the filter is fresh leave it alone.

Best strategy IMO for stock trans is keep the bypass, add the 6.0 cooler. That's it.

For the trans filter, did you use the 2X4 or 4X4 filter? Always use the 4X4, even if your truck is 2X4. Post 1999 pans are deep enough for the 4X4 filter so that's the one to use.

Do you have a solid way to get codes, like FORScan and a quality OBD2 adapter? I'm thinking there may be trans codes that can help.

 

I installed the 6.0 cooler when I got the truck, and the bypass delete. I assume the rebuilt trans now has a bypass, but I’ll have to check. As long as I know this trans doesn’t get too hot and is serviced regularly I see the bypass as a net positive.

 

I’d have to agree with the thought that if the engine is spinning so is the pump. I’m pretty sure the pump is in the torque converter, not the transmission. I’ve heard the trans gets very hot when reversing with a heavy trailer, but I figured that was because of the tall reverse gear. You could save some of the old fluid and get it analyzed. I’m not sure if there’s tons of data on atf, but there definitely is for used motor oil. Blackstone-labs and Polaris labs are two I know about.

 

If the engine is turning the pump is pumping. It definitely flows through the coolers in both park and neutral.

I am absolutely certain that the pump is in the transmission, not the torque converter.

That's part of it, but the real problem in reverse is that there is so little airflow over the coolers in reverse.

 

I already have a history going with Blackstone lab, I'll grab one of my extra bottles and send one in for the transmission.

 

Mark,
Best fluid service/replacement process?
Drain & fill pan and torque converter?
Full exchange service (1 for 1 exchange operated by transmission)

I have my thoughts based on my experiences with Subarus over the last thirty years. There isn't one answer for all.
I am not savvy with the 4R100 and what it likes best.
Truck is basically stock, daily driven, tows 5k once in a great while, only have the SCT4 on performance tune. Currently at 222k, last serviced (drain & fill) at 175k, owned since 150k, I believe it is the original transmission. TIA.

 

Here is how to change the ATF in a 4R100: https://www.ford-trucks.com/articles...-transmission/

Any MERCON V rated fluid will work. My favorite is Mobil 1 Synthetic ATF.

 

@2.5gl do you have any updates to this? I have a buddy who is experiencing the exact same issue...he is low on fluid, but its pink and the filter is in the green so the flow is happening.

Thanks