Ok I am going to have to fix my own transmission in my truck since I recently became unemployed and we use this truck to haul my wifes food trailer.

I know you guys are going to have at least as much experience as the local transmission shop that wants what may as well be a million dollars to work on it...and certainly not going to the stealership.

So hello from Arkansas!

Ok getting dirty.

Its a 99 F350 4WD 7.3 with Auto. Just clicked over 202K miles. Mileage is terrible, but you know when you put your wife in a truck hauling a trailer, you can't have too much truck.

Only mods I have done are a trans cooler from a 6.0. I dropped the pan and replaced trans filter (which really did not fit tight but as far as I know is still in place) and I changed the fluid but did not drain the torque converter. Fluid level is proper with the Ford stuff, and does not run hot. Ok there was some gunk in the pan, very fine pastey stuff you know, around the magnet but I did not think it was out of the ordinary but I could be wrong. The previous owner said that he had the transmission replaced at some point in the trucks life. Rebuilt/replaced...i dont know. The truck has always been sort of hesitant about up shifting, but previous owner said that was because of something done when he had it rebuilt... I just don't know.

Overdrive Light started flashing. Will not flash for first few minutes of drive and seems to come on at a certain speed, not sure. When it does come on it shifts hard, but still hits all the gears and the overdrive off function still works.

I replaced the TSS sensor on top of the rear diff and disconnected the batteries, but the light began flashing again sometime later.

I took it to a transmission shop and had them pull codes.

So I have a print of mechanical and electrical codes.

They are:
Key On, Engine Off Codes Fix First
P0743 TCC System Electrical Fault.
P1298 Injector Drive Module Fault.

Memory Codes
P0743 TCC System Electrical Fault.
P0603 Internal Control Module Keep Alive Memory Error
P1728 Transmission Slip Error-Converter Clutch Fault
P0741 Torque Converter Clutch System Stuck Off.

Ok....now after all that typing, my question is

What do I do first? Of course I am looking to repair only what is wrong, starting with the easiest/cheapest. But if I have to drop it out and deliver it to a re-builder I will do that too. I just want to know what does a guy do to fix this problem without selling all the furniture in his house or getting a divorce.

Thanks in advance.

 

Welcome to the site..

You should address the TCC codes first. 743 TCC electrical fault being job one,, and quite often is a solenoid pack issue, (should check the harness connector as well for pin damage) and, if the trans needs to be built, pack should be replaced anyway. The concern for more forced or hanging up shifts, would make me question the previous build and weather the current issue has ‘some’ relation.
The OD flash usually indicates mismatched or unexpected ratios, and/or slip conditions.. Generally, the code will produce problems with the OD shift/lock up.
The fine metallic debris on the magnet is pretty normal. Any large pieces held there or concentrations of debris in the screen is an indication of hard or wear part failing in most cases.
These trans need a few specialized tools for pump removal, to compress some of diaphragm/springs within the main and sub assemblies, other more just basic tools (picks, internal snap ring pliers, torque wrenchs-in/lb and standard ft/lb etc ) to help break down and assemble the units. Building them isn’t overly difficult if you have these tools, good well illustrated reference materials, a camera during disassembly is a good idea, and lots of clean bench space... Solenoid pack replacement is pretty straight forward,, pan removal, harness disconnect, needing just torx driver sockets for the pack.,
Ive built quite a few, if you need help with the tasks...

 

First order of business is to buy a new or refurbished solenoid pack, fluid and filter and go to work. Looks like I am going to spend 300 or so dollars on all of that (I think I have a spare pan gasket) a few hours doing it and then take it out for a drive and see if codes come back.

Any recommendations on source for the solenoid pack? I guess this time I will drain the fluid from the TC. If I find a lot of junk in the pan after the 8000 or so miles I have put on since I last changed the fluid and filter, my plan may change.

I am just guessing, but is the torque converter the next likely bad/worn part? And if so... can they be changed out without dropping the transmission? I am really hoping the pan is clean.

Thank you for your reply. I will post results here as soon as I have some.

 

I’ve most often used Fords parts, but if guaranteed assured, I’d have no problem ..

The TC/clutch when failing tends to shudder the unit after final lock up. If the TC slips, you generally will see friction materials suspended in lube, or sludge like deposits collected in the pan. The trans needs to be removed to change out the TC. I’d think it was replaced during its last build. and unless a lower mileage failure and now service life questionable,, or a used trans was sourced, it wouldn’t have too many miles on it.
When you change out the pack, make sure the connector body is reasonably clean so it slips out if the case, and be careful separating it from the valve body gasket. They normally separate right off the gasket, but...... Clean the case bore for the connector pass through, and lube the o-ring to aid its travel...

 

Ok here are two photos of what is on the magnet in the pan. This is much less than I had when I changed the fluid 5 thousand miles ago.

I removed all the torx bolts from the solenoid pack including one 10mm nut that was on a corner. I could not break the pack away by hand. I removed the yellow plastic cover thinking some other fastener might be under there and there are what look like many smaller torx but they seem to be in the middle of the valves. I did not remove any of those. I used a very small trim button removal tool and tried to pry it loose, but was too close to a gasket that looked very difficult to replace from under the truck. I just got tired of it dripping in my face and decided to post these pics and get some clue as to how the solenoid pack is suppose to be removed.

So is there a trick to it or am I just being too easy with it?

 

Well I don't want to jinx it, but I think the solenoid pack replacement fixed it. I drove it pretty hard and the overdrive light did not come back on.
Not only that, it shifts better by far. No hesitation on up shifts at all!
Thank you for your help I am pretty damn relieved. I think after parts and fluid I am at about 200 dollars. That includes refurbished solenoid pack, ford filter and fluid. I know the bill from a transmission shop to do this work would have been at least 1000 dollars. I am happy, wife is happy and truck seems fine.

 

Good deal, thanks for the update!

 

You called that issue and fix dead on. HUGE load off my family.