P1744 P0743 codes trans TC lockup problems

[hvywt77]

I was pulling my buddies '78 Bronco home from Michigan last week it was hot, out about 93°. Pulling fine for 250 miles at about 70 mph. Stopped to get drinks, and idled for about 10 minutes. Then hit stop and go traffic and cruised at 55 mph for a while. I noticed that when the traffic cleared up and I would try to creep back up to 70 mph the excursion was reaching 2100rpm and only going about 63mph. Previously it was running 70 mph at 2100rpm just fine all the way up to michigan. OD was working and I could turn OD off and it would shift out of OD and back in when activated. It just felt a little mushy. No engine lights not other signs of trouble. I do not have a trans temp gauge, just the idiot gauge on the dash, which of course tells nothing useful after warmup. Continued to ease it around 465 in Indianpolis onto 65 south. It was taking more and more power to maintain speed and climb ramps etc. We stopped to check out some things and trans fluid level was ok, color was ok. We turned the excursion off and started it again, and then we had check engine light on. We contined the 40 mile drive home and unloaded. The truck felt like it would go into OD but the TC would not lock up.
A day or two later pulled the codes and got P1744 and P1743. I also had a blinking OD off button light. I cleared the codes and they have come back already. It shifts ok, maybe a little rough 3-4 shift. OD seems to work ok, i have not taken it back on to interstate and I have not hauled a trailer or anything since I got back.
SO i have done some searches and I can see there was a TSB for the shift solenoid and that there is a new part number. THis is from the dieselstop Flashing OD Light. Solenoid Problems? - Diesel Forum - TheDieselStop.com
I have found P/N F81Z-7G391-CB online at tousley and others for a little under $300.

Has anyone pulled these same codes or had problems with lockup? What did you do to fix it?

History: I bought this 2002 Excursion in Dec 09 with 191K miles on it. Dealer said the trans was rebuilt at a local shop. It now has 195K miles. I have not serviced the trans, the excursion appears to have been serviced at ford dealer, as it has motorcraft wipers, batteries, paint dots on drain plugs etc.

Any comments or input would be appreciated. I am located in southern Indiana.

[taylor I]

My OD light is flashing and they told me it was my TCC solenoid and its only about $40 but i dont know where it goes. Also i had another 7.3 that did the same thing but we changed the censor on top or the rear axle and it fixed it, thats only about $20 at parts house.

[hvywt77]

I got my parts from tousley yesterday and got the TCC solenoid pack replaced. turns out the excursion had the current part number with the CC revision, but it did not have a ford logo, so I do not know if it was aftermarket or what. I also found that the solenoid pack was held in with T30 fasteners, and there was one stud with a 10 mm nut. The 10mm nut had come off and was in the bottom of the pan. This was not a bad job to do, a little messy as it usually is when you drop a pan of an auto trans. I definately reccomend tousley ford for parts, they had the best price online, and none of my local dealers (within and hour drive) had the parts in stock anyway. cleared the codes and test drove to work today and it seems to be shifting fine and going in and out of lockup/overdrive well.

[FordNutz]

Good work man it's not too bad. Like you said, a little messy just make sure you have a lot of shop rags around. What color was the plastic cover of the old solenoid?

[hvywt77]

yeah it was ok...it was orange, well they both were orange. funny thing the old solenoid pack was the same revision level CC of the new one. However the old one did not have a ford logo on it. It just had numbers on it. I dunno if you can get them from the aftermarket but, The new one had ford logo. Not sure that it matters. The dealer where I bought the excursion said that he had the transmission worked on for a shifting issue. I dunno what they did, but I could tell the valve body had been off before, just from marks on the bolts. Its seems fine now, i have driven it a couple times today. before when I cleared the codes they came back as soon as I drove it again. I think I am good for now. I think it got hot while i was running 70mph towing and when we stopped to get a drink it heat soaked the tranny and then when we started up again the solenoid went open I guess. thanks for your advice.