I've got a 2001 F550 7.3 187,000miles on the od. Been having intermittent issues lately. Half the the time I have to shift it to nuetral to get it to start, won't start in park. It will sporadically not go into gear, engine will just rev while in drive It will eventually start move. Sometimes moving the shifter back and forth will correct it, other times it won't. At times it acts like it doesn't know what gear to go into. It will do this while the transmission is cold, or hot. It has gone into limp mode with the of light flashing. It goes back to normal after a while. Sometimes it acts up after going over a bump. The rest of the time it runs fine. Did a flush, just the usual amount of crap on the magnet, no chunks of metal. Fluid levels are good.

 

Sounds like you have 2 separate issues going on...…………… the 1st is the shifter interlock......just need to follow the troubleshooting procedures.....could be the brake pedal sensor/switch is tired....the second is likely related to the transmission cylinoid(s)…..again, follow the trouble shooting procedures by checking if they are functioning.....it may be time to replace those.

 

Posted on on the 7.3 forum as well. It was suggested it may the transmission range sensor. Apparently the nuetral safety switch that prevents you from starting while in gear is incorporated into that. Picked up a new one and will post the result. Parts store couldn't pull any codes.

 

When it does this codes are stored. You need these codes to be able to diagnose what's wrong.

Part stores do not have the right scan tools to read transmission codes. You need either a good independent repair shop or a Ford dealer. There are codes, you need to get them,

 

Thanks soon as I can find a good independent shop I'll get the codes pulled. In the mean time I replaced the transmission range sensor. The old one was without a doubt bad. Took it off and water had gotten past the seal on the electrical connector. The sensor rattled when shook and some water came out. Replaced with new and cleaned up the connector. The truck starts rights up in park now, no issue. Haven't had a chance to take a good test drive to see if that was the only issue. I find it hard to believe that little sensor could cause all the problems.

 

Got the codes pulled. P0733 incorrect 3rd gear ratio and P1247.Boost low pressure. I'm guessing the P0733 has something to do with the issue I'm having with the transmission. The P1247 probably has to do with my leaking up-pipes. I have replacements that have been sitting in the garage waiting for me to have time for them. Further information is while I was going over the transmission I was about a quart low on the fluid from when I did the flush a couple of months ago. Must have miss-measured while flushing. Sometimes it's hard to see when the fluid changes color after a few beers.

For future reference for everyone out there. I was unable to find a garage working on Saturday that could pull the codes. After some research found a free option. Downloaded FORScan Windows version (Free). Connected right to my BAFX OBDII Bluetooth interface and pulled the codes the parts store said weren't there. They also have a free (FORScan free) and pay (FORScan Lite) for $4.99 Android versions. The free android version would not connect to my adapter. Did not try the pay version for android. Took the card of my Google account after my son spent $80.00 on World of Warships. The Windows version had connectivity issues until I discovered my phone kept turning on it's Bluetooth and connecting t the adapter before the laptop could. Great program and easy to use. Gave me more information than Torque Pro that I've been using.

 

Pulled codes again today. Got P0733 (Gear Three Ratio Error), P01247 (leaking up-pipes), P0781 (1-2 shift malfunction), P0541 (delete installed), and P1106 (Dual Alternator Lower Fault (Control). Any ideas?

 

What does the ATF look and smell like? Red? Brown? Black? Burnt odor?

When you have two threads going on the same problem you tend to get sent in different directions. See your other post.

 

The fluid is pretty and pink. Just did a flush maybe two months ago now. At the time of the flush it was red, not burned just well used. There was some not excessive powdered clutch material on the magnet as I have usually found during a flush. I checked the fluid level the other day after it acted it up and found it was a quart low. Admittedly, I probably didn't put enough in while doing the flush. It was getting late and was hard to tell the difference in the change of color while flushing. I checked the bolts under the dash, they were good and tight. I'm no longer having the no start issue in park since replacing the range sensor. I've been unable to reproduce the shifting issue since replacing, but admittedly I haven't driven it more than 10 miles. I'm going to clear the codes and see if anything comes back.

 

Cleared codes and took it for a 30mile drive. No issues with the transmission. No flashing OD light or CEL. When I got home pulled codes P0541(delete installed) and P1106 (no idea).

 

Have you checked the bolts on the steering column that hold the shifter cable in place? If that end of the cable is moving around, it could do a lot of what you're seeing.

 

They were good and tight. I haven't had any other issues with the transmission since replacing the transmission range sensor. I opened it up and water had gotten into it. It was pretty grimy and one of the spring loaded contacts inside had broken loose. I cleared the codes and the only ones that came back are the AIH delete, the lower alternator (factory dual alternator set up), and low boost (leaky up pipes). I'm leaning towards getting the AIH delete code eliminator and will pull the lower alternator to test when I get the chance. Not to concerned about the alternator at the moment. The upper is only a year old. The up pipes I'll get to in July when I have a few weeks off (parts sitting in the garage). I'm hoping the sensor was the only problem with the transmission.

 

My hope has died along with the transmission. Driving on the interstate at 75mph, going up grade on a bridge, and lost all forward gears. Coasted off the interstate and on to the side of the road. Reverse still worked fine, but figured driving home 8miles in reverse would have been a bad idea. Had to get towed home by a dodge with a Cummins. No transmission codes this time. Just got the bad aux alternator, AIH delete and the low boost plus low exhaust back pressure again. I'm guessing that's my leaking up pipes. Looks like new transmission time. She made it 188,888miles, may she rest in peace. I'm poor though and need affordable options. I'm located in Punta Gorda, Florida. If somebody knows a guy let me know.

 

Well, just for to satisfy my curiosity I drained and dropped to pan. The magnet looked like a porcupine from hell and the top of the filter looked like Tinkerbell and all her fairy friends had a party leaving glittery pixie dust everywhere. There were a few pieces about a half inch long but most were small. I'm sure there is more in the filter, cooler, and every nook and crevice of the transmission. A lot of it was on top of the filter when I dropped it. Didn't even bother tightening the pan back up. Just stuck the filter back in and put the bolts in finger tight. New transmission time.

 

Have you decided what your going to do about a transmission? Mine is still going but having a slight leak coming from tran-bellhousing inspection plate.