2008 4.6 6R60 transmission question

[pjw73nh]

Does the 6R60 transmission have any "anti-damage" safeguards built in to it?

I recently solved a misfiring issue with my 08 4.6 LTD (bad coil). When it would act up and miss was under heavy load. Like stomping on the accelerator to pass a slower vehicle. Or going up a steep hill and having it down shift.

What puzzles me is that when this misfire issue was happening, it would rev high, slam into what ever gear is was searching for, chirp the back tires, the traction control light would flash for a bit, and the engine would then be revving very high as if it was in neutral. Like the trans was quickly and temporarily disconnected from the engine.

Yet, as soon as I let off the gas pedal and the rpms came back into a normal range, it would fall into gear as if nothing had happened and continue on its merry way until the next occurrence.

It threw my diagnosis off for a bit because until it finally set a P0301 code (after many occurrences), I was thinking it might be a transmission or TCM issue.

So, my question stands. Does the 6R60 have any safeguards against self destruction?

Thanks.

 

[2000StreetRod]

TCM protection

There is a 3rd gear and 5th gear failsafe/default mode initiated by the TCM when the TCM temperature is out of range. If the transmission fluid temperature increases to 125ºC (257ºF) or higher, the TCM employs the cooling strategy. The strategy uses a specific shift and torque converter lock-up clutch map. This map allows torque converter clutch lockup
and gear shifts to operate outside of their normal operation. This will reduce the engine speed and/or slip in the torque
converter, therefore reducing heat generated by the engine and the transmission. If the transmission fluid temperature increases to 137ºC (278ºF) or higher, the transmission will use the default (limp home mode). If the ATF or TCM temperature exceeds 170 deg. C (338 deg. F) - 140ºC (284ºF) on the Land Rover - the TCM will shut down the transmission and then itself. However, in your case I suspect the PCM initiated self protection due to the misfires.

 

[pjw73nh]

2K SR, Thanks for such an informative post. Nice to have that info. I tow a #5400 travel trailer about 1500 miles each summer on 4 or 5 different trips, and I baby the transmission. I watch the temp closely. I never use overdrive and rarely exceed 60 MPH. While towing during the summer, on rare occasions my trans temp peaks at 228 F, but most of the time is is 208-222. When not towing it never goes above 195.

Nice to know about the temperature thresholds and the actions that follow. I am hoping that the misfire was the cause of the erratic transmission behavior. Thanks.

 

[2000StreetRod]

monitor?

I'm not familiar with the 4th generation. How do you monitor the transmission temperature?

 

[pjw73nh]

I use a scangauge II. http://www.scangauge.com/products/scangaugeii/

In its native form it is a simple install (Connects to OBDII connector) and if you take defaults it will provide some good data. If you dig a little deeper into programming it, there are a multitude of parameters it can display.

I have mine to display Coolant Temp, Trans Temp, Charging Voltage and Instantaneous MPG.

It's a pretty nifty little device... I think I paid abput $120 at Autozone a few years ago.

 

[2000StreetRod]

Scangauge

I use an SCT X3 PowerFlash when I change something and datalog to my laptop but I'm starting to look for something to semi-permanently display selected pids such as ATF temp. The cost of a Scangauge is comparable to what I would pay for a single gauge but the Scangauge displays multiple user selectable pids so its a pretty good bargain. Unfortunately, I'll still need single gauges for engine oil pressure, AFR and boost.

 

[Explorer_PL]

On similar topic, can a regular code reader retrieve transmission codes ?
I am using Innova 3160 and I never saw 700 codes, even when I am having issue with my tranny currently.

Or maybe it never generated the code.

Dealer says I need new mechatronic.

 

[pjw73nh]

Ex-PL, I use the same scanner and I've never seen any transmission or 700 codes. Maybe I'm just lucky. So far...

 

[2000StreetRod]

can't read transmission codes

On similar topic, can a regular code reader retrieve transmission codes? I am using Innova 3160 and I never saw 700 codes, even when I am having issue with my tranny currently. . .

I think the Innova is unable to read transmission codes: Major Discovery for OBD-II Scans!!!!

The 3160D has a Ford Enhanced menu selection but there's no mention in the manual regarding its ability to read transmission codes. I suspect the Innova is basically a generic code reader.