Flashing O/D light - Diesel Forum

phreetogo · 11-20-2006, 08:15 PM

Just bought this truck and now the O/D light is blinking. Mechanic said it is showing a torque converter code. Called a few different places and got a couple different stories.
One said the tranny is fine and it just need the torque converter replaced. He said I could drive it for "a while" without damaging the tranny.
Other said the tranny needs to be replaced if the torque converter is going bad.
Anyone have this experience? What happened? What did you do?
The transmission is now in limp mode.
The light went off for a day and the trans shifted fine with no slips, hard shifts or unusual revs. Seems like the trans is fine when it wasn't in limp mode. Now it is blinking again and back in limp mode.
Any insight or suggestions??
1996 f250 4x4 automatic

Stroker85 · 11-20-2006, 08:40 PM

i have heard of this happening to a buddy of mine. Everybody said that it was the t/c slipping he replaced the t/c and it quit. the tranny went 15K later. hope that will help

jcal · 11-21-2006, 04:06 AM

I had the same issue with my 95 F350. Not long after buying it the OD light started blinking. I posed the question on the board here was told the Torque converter solenoid block (TSB) was bad or the torque converter was bad. I took it to the Ford dealer they said replace the transmission, cost $2675.00. I took the truck to a local top-notch trans-mech who after diagnosis said one of the valves in the TSB was sticking. Could replace the TSB for $178.00 + labor total cost was $475.00 however he said my trans was worn and would need to be replacement within at least 25K miles. My truck at that time had 125K miles on it,the previous owner towed a 11K fiver most of those miles before I bought the truck. At 148+K miles the trans went out. Found a friend at a ford dealership who sold me a ford trans for $1878.00 that included all oil and filters and 36K mile warranty. I changed the trans out myself, easiest trans change job I have ever done?
Good Luck
Love My Truck

KCovey · 11-21-2006, 12:13 PM

Its the TC and or valve body. The reason for limp mode is the PCM detects slipping. Something is slipping you can bet on that. [img]/ubbthreads/images/graemlins/frown.gif[/img]My advice PARK IT. The more you drive it the more you risk polluting your tranny with clutch material/metal. If you park it you have a good chance of getting by with only a TC and cooler replacement. Good luck and oil up that wallet. [img]/ubbthreads/images/graemlins/grin.gif[/img]

Racer_X · 11-21-2006, 01:14 PM

How many miles is on the unit? See if the shop will give you the code # and post it here. Ford "authorized rebuilds" haven't had the best reputation for long life. I'm surprised to hear they will honor the warranty on a cash and carry sale [img]/ubbthreads/images/graemlins/confused.gif[/img].

I wouldn't drive it in limp mode. That is meant to get you to service without a tow.

phreetogo · 11-21-2006, 07:41 PM

This truck has 156000 on it and the tranny. I believe the code was the P1744 could be wrong. The light went off again today and then went back on, on the way home from work. I was quoted on a ford rebuilt tranny with parts and labor at 2,800 with a 3 year 75,000 warranty.

Paul H · 11-21-2006, 08:07 PM

Here is something to go on.
Take it out on a hill in OD and ease down on it. If the RPMs climb more than the truck speeds up, meaning if the rpms go up say 500 rpm but the truck does not speed up then the TC is in deed shot. Once they strip the clutch material off the lock up clutch, all that goes through the tranny and clogs the cooler in the bottom of the radiator.
If the RPMs hold solid and the truck gains speed then the TC clutch is not slipping and could be electrical not the tranny.

Reset the computer, and start it up and see if it flashes before putting it into gear, if it does then check the neutral start switch on the outside. This could be telling the PCM it is in one gear when really it is not and throw a slip code.

Son's 96 F 250 just did that and shr neutral start switch cured it.

squirl919 · 11-21-2006, 08:46 PM

mine 97 was doing the same thing and i tried to make it last as long as i could. end up buy a new trans at total installed price of 3800.00$. but thats the upgrade tranny that im not suposed to be able to break, we'll see how long and how much power we can put through it.

Racer_X · 11-21-2006, 09:24 PM

[ QUOTE ]
This truck has 156000 on it and the tranny. I believe the code was the P1744 could be wrong. The light went off again today and then went back on, on the way home from work. I was quoted on a ford rebuilt tranny with parts and labor at 2,800 with a 3 year 75,000 warranty.

[/ QUOTE ]

That is the code for converter clutch slip. The circuit involves the PCM, the solenoid pack, the pump valve, and the converter itself. Mechanical Wear can cause the code or a faulty sensor.

You can do the test and check for lockup--rpm should drop 2-300 @ 50 mph if lockup is working. The TC clutch material can clog the cooler and starve lube. That's the danger of driving it, plus extra pressure when it goes to limp or fail safe mode.

Nit · 11-22-2006, 09:51 AM

find a local guy here to give you Tranny shop info, you are looking at replacing teh TC now and addign a large cooler , Tru-cool 4590 is what you need, add a shift kit too at teh TC time, but do it now, other wise pull fuse #9 under the hood to reset teh PCM when teh OD light flashes and save up money for a new tranny in 3-6 months.

donseye · 11-22-2006, 01:13 PM

How Far are you from colorado springs

phreetogo · 11-22-2006, 04:02 PM

Large Cooler?? Shift Kit?? What would be the purpose of these? John

phreetogo · 11-23-2006, 11:14 AM

I pulled the number 9 fuse but it didn't reset the flashing light. Just kept on flashing. Maybe I'm doing something wrong. Anyway, thanks for all the advice. I live about 3 hours from colorado springs. I posted that before and it got deleted for some reason. Also another post I started is gone? Does this happen regularly?

donseye · 11-23-2006, 01:23 PM

If you want call Travis his number is 719-574-8104. He can guide you to your problem, Maybe he can tell you what to do over phone, good luck

Nit · 11-23-2006, 06:46 PM

sorry forgot to tell you to leave it out for at least 20 mins, my mistake.
You need a larger cooler becasue teh stock one is crap, and a shift kit too quicken up teh shifts as Fords programming is too loose.

You need a new TC no question about it.