66RFE issues

[CVORider59]

My 2012 2500 HD 4x4 with 6.7 cummins seems to have entered into SafeMode. The transmission starts a full slippage in fourth gear, then continues slippage in all lower gears until the truck slows enough to manually shift into first or second gear. Drove the truck home in third gear, 8 miles. The motor and transmission temps were all in the normal range, engine 197, tranny 152. The truck has had all deletes done for over 8 years and no problems. This has occurred totally without warning, no drops in performance or any other signs. I use the truck primarily as a weekend/recreational vehicle, trips to the lumber yard and towing a Toy Hauler to motorcycle rallies. Total millage is just over 90,000 miles. The only issue ever with the truck was worn front spindle bearings, replaced the entire spindle assembly on both sides. Some that i have visited with feel the problem is with the valve body in the transmission and recommend a complete service and maybe the valve assembly upgrade. Bike rally season has started and I really need this fixed.
Anyone experience the same?
Remedies?
I limped home and did the three click ignition trick to see all my error coded vie the trip "b" odometer. It shot me 21 different codes. Many were from all the deletes i have, but the others really dont make sense. They range from low voltage, high readings on some circuits, to the dreaded 0606 Internal Control Processor. All the crazy codes tend me to think maybe a bad wire, draining voltage from the processor, low voltage just makes technology do sketchy stuff. Don't want to take it to a dealer, because all they see is $$$$.
Has anyone out there ever encountered the Safe Mode aka long drive home mode? Were you able to remedy or go straight to the dealer?

 

[bigdodge]

If you mean by full slippage that it just revs when it hit 4th gear it's probably the accumulator piston plate has come off. If it hasn't stopped the screw holes it would be an easy fix.

 

[HEMIMANN]

If you have the Cummins engine, you have a 68RFE, not the 66RFE. This trans was beefed up some to handle the higher torque of the diesel, otherwis they are similar.

Yeah, your valve body is losing it, just like many others. They warp, wear, and leak with time. You can get an upgraded body from Sonnax, other than they're sold out right now (tells you something, eh?), and you must do a re-learn or it won't shift right. The PCM apparently won't do a secondary re-learn after the initial.

 

[burner71]

I have the 2012 2500 5.7 with the 66RFE
Mine did something similar and I had the upgraded valve body and solenoid installed. Been good since.

 

[HEMIMANN]

I have the 2012 2500 5.7 with the 66RFE
Mine did something similar and I had the upgraded valve body and solenoid installed. Been good since.

What valve body did you have put in? Sonnax rebuild?

I think you have the 545RFE - the 66RFE was for the 6.4L Hemi - your avatar says 5.7L Hemi?

 

[burner71]

Yes Sonnax.
I definitely have a 66RFE in my 5.7
Its actually the second one. The first blew out a few years back.

2012 was the first year the HD gasser got the 66RFE.

"The 2012 Ram 2500 Heavy Duty pickup also gets a new six-speed automatic transmission, called the 66RFE. It replaces the previous Hemi V-8 gasser's 545RFE gearbox, which was shared with the light-duty Ram."

2012 Ram Trucks Receive New Six-Speed Transmissions | PickupTrucks.com

The Ram Truck brand is increasing the number of gears available for its 2012 light and heavy-duty pickups with the introduction of two six-speed transmissions.

news.pickuptrucks.com

 

[HEMIMANN]

Yes Sonnax.
I definitely have a 66RFE in my 5.7
Its actually the second one. The first blew out a few years back.

2012 was the first year the HD gasser got the 66RFE.

"The 2012 Ram 2500 Heavy Duty pickup also gets a new six-speed automatic transmission, called the 66RFE. It replaces the previous Hemi V-8 gasser's 545RFE gearbox, which was shared with the light-duty Ram."

2012 Ram Trucks Receive New Six-Speed Transmissions | PickupTrucks.com

The Ram Truck brand is increasing the number of gears available for its 2012 light and heavy-duty pickups with the introduction of two six-speed transmissions.

news.pickuptrucks.com

Apologies, I did not know this.
Wow FCA really messed around with transmissions.

Well, at least we can change oil on them without having to set up an auto service center.

 

[Burla]

Valve Body is your brains and the weak spot of these rfe's, if you have a torx bit it is simple plug and play if you remove transmission pan. Mise well change solenoid with it, get the white one. Losing overdrive is the classic symptoms with these. Get a metal thread upgrade with canister filter, see synthetic options for the filter and you will need 8 qrts of tranny fluid to button it up. You may or may not need a quicklearn, that is what it is.

But, you have the cummins, so you need to decide rebuild or not, because it is likely your clutches are at the end of their life if they have a lot of miles with that engine. If you need a rebuild later all this work is likely a waste. If you do it yourself it makes sense imo, maybe 1200 bucks worth of stuff give or take. I use redline c+ for transmision fluid, ester based smooths out shifts and is heavy duty fluid.

 

[buckeyexx]

If you have the Cummins engine, you have a 68RFE, not the 66RFE. This trans was beefed up some to handle the higher torque of the diesel, otherwis they are similar.

Yeah, your valve body is losing it, just like many others. They warp, wear, and leak with time. You can get an upgraded body from Sonnax, other than they're sold out right now (tells you something, eh?), and you must do a re-learn or it won't shift right. The PCM apparently won't do a secondary re-learn after the initial.

Looks like Rock auto has the sonnax valvebody without the solenoid pack in stock. I personally would rather have it with if it were me but if you could verify the solenoid pack is good then you can just swap it over.

 

[HEMIMANN]

Looks like Rock auto has the sonnax valvebody without the solenoid pack in stock. I personally would rather have it with if it were me but if you could verify the solenoid pack is good then you can just swap it over.

Well, it's all moot for me assuming I can't relearn the PCM with a tuner on it, and not be able to add a tune later on top a relearn.
Way too much software in these things.

 

[Bmags]

Good luck!