5R55S Questions on Compatability

[2k05gt]

I am having some Tuning issues with the 2008 GT 5R55S Low Milage Transmission that I installed into my 2005 Mustang GT. Some Question the Compatability of the 08 to the 05, there were a lot of electronics changes between the years.

I can't get rid of the Blinking O/D off Light, it comes on in stop and go traffic. the transmission has less than 9K miles on it so I doubt it's a bad transmission.

Does anyone know of any changes in the transmissions from 05 - 08?

 

[TexasBlownV8]

I know the engine wiring harness (includes trans wiring) is different between 05/06 vs 07+. Using the '05 harness, there could be a sensor/control or two that have changed pinouts or something. Not sure if anything internal changed.

I'd like to know the answer, too.

If you can get ahold of a '08 and '05 wiring diagram, you might be able to see if there's any differences.
Seems I've heard of this same issue before, somewhere.

 

[ixtlan]

There should be a code for whatever is causing it.
May help zero in on where the issue is.

 

[2k05gt]

There should be a code for whatever is causing it.
May help zero in on where the issue is.

I checked no codes...
The O/D off Light starts blinking when in traffic at 5 mph when I let off the gas and coast.

 

[2006BlackGT]

I checked no codes...
The O/D off Light starts blinking when in traffic at 5 mph when I let off the gas and coast.

I had the same problem - it is in your tune. Ask your tuner to look at the trans portion of your tune.

 

[2k05gt]

I had the same problem - it is in your tune. Ask your tuner to look at the trans portion of your tune.

I have, we have been working on getting rid of it but he's not sure what to change. does anyone one know what to change

 

[ocpony]

The O/D light will flash a two digit code that can be looked up in the service manual. I think there are 5 or 6 different codes it can flash. The manual will then give you an idea of where the problem is. Mine flash a code for no conv. lockup. The modulator valve in the valve body was sticking. I had to ream the hole out lightly with a pencil wrapped with 400 grit using my drill. You could have a different issue tho.

 

[2k05gt]

The O/D light will flash a two digit code that can be looked up in the service manual. I think there are 5 or 6 different codes it can flash. The manual will then give you an idea of where the problem is. Mine flash a code for no conv. lockup. The modulator valve in the valve body was sticking. I had to ream the hole out lightly with a pencil wrapped with 400 grit using my drill. You could have a different issue tho.

What do you mean by "Flash a Code" ??? My SCT Hand held does not show any codes. the Light itself just flashes on and off over and over again until I turn the car off, then when I restart the car these flashing stops, until I get in stop and go traffic again, get up to 10 mph light accel and let off the gas, I feel a slight clunk and the light starts flashing. then the trans starts shifting hard and hangs between shifts. I am told this means it's in Fail Safe mode...

 

[ocpony]

My xcal didn't show a code either. Pay close attention to the O/D light. It will flash on and off at different rates like morse code. I think mine was 2 flashes then a pause and then 3 flashes for a 'code' of 23. I can't remember the pattern for sure but you sould see a recurring pattern in the flashes which will give you a 2 digit code that can be looked up in the service manual. I hope this helps.

 

[2k05gt]

No it did not help, It happened twice on the way home, I watched very closely and it was even on - off - on - off - on - off - on - off - on - off - on - off - on - off - on - off - on - off - on - off - on - off - on - off - on - off... So on..

At the next long stop I turned off the car and restarted to clear the light, and like clock work, stop, go stop, go, Clunk on - off - on - off - on - off .... FUCK.. I hate this damn thing..

Hey But Thanks for the heads up, I will look into the codes more.

I Guess I have to move out of the DC area, Traffic Sucks here and My Car hates Traffic,

 

[TexasBlownV8]

My xcal didn't show a code either. Pay close attention to the O/D light. It will flash on and off at different rates like morse code. I think mine was 2 flashes then a pause and then 3 flashes for a 'code' of 23. I can't remember the pattern for sure but you sould see a recurring pattern in the flashes which will give you a 2 digit code that can be looked up in the service manual. I hope this helps.

Lol, sounds like the airbag light on mid-90's fords: would flash the code for the problem detected (pre-OBDII).
That would help, to know what it's telling you.

 

[ocpony]

well it could be code 11 then. If I get a chance to go by ford I will see if I can get them to look up the codes. There are only a handle full if I remember. In my experience if it is flashing then it should be a code. If it comes on and stays on then it is a constant failure of something in the tranny. My main tranny mechanic at ford is no longer working there anymore so I can't guarantee I can get the codes tho.
I have had my tranny apart 3 times on the valve body myself and had it upgraded with the bronze bushings and several other upgraded/ revised ford internals during 3 rebuilds. I love the tranny but at 500rhp and up it can be very problematic. I have probably 300+ drag runs and 30K on the tranny and several road coarse weekends so far.

 

[MSgt46270]

Every time I had my O/D flashing on me I ended up having to rebuild my trans. Hope it's not the case for you. My trans has been rebuilt 3 1/2 times now.

 

[Pumpkinfish]

Every time I had my O/D flashing on me I ended up having to rebuild my trans. Hope it's not the case for you. My trans has been rebuilt 3 1/2 times now.

+1

I had a tuner who kept clearing the code while tuning and it turns out my Level 10 was trashed. I would get your car to a Ford dealer to read the code, then take action. You can also call Level Ten and talk to them. They were super helpful helping me diagnose as much as I could in my garage. I ended up bringing my car to Level Ten and had them remove, rebuild and re-install. Car feels awesome right now.

 

[2k05gt]

Every time I had my O/D flashing on me I ended up having to rebuild my trans. Hope it's not the case for you. My trans has been rebuilt 3 1/2 times now.

Like I said it's a very low mileage 2008 Transmission The car was stock and a show car never raced. So I really doubt it's a bad transmission, if anything it's a tune issue between the 2005 PCM and 2008 PCM.

 

[NastyStang113]

Who's tuning it?

 

[klaw]

I met a guy that trashed his '07 5R55S after installing a Procharger. He tried an '05 or '06 replacement and ran into compatibility issues. After talking directly with Ford he was told that the internal electronics were changed in '07 and that he had to find an '07 auto to get it to work with his '07 ECU. I had a low mileage '07 out of a wreck that I sold him. He had it built and his car is up and running fine now. I might be able to get more details if I can still find his number. PM if you want me to try.