68RFE death codes

[Caboverbob]

'17 2500 w/6.7 & 68rfe.

Check engine light comes after hard shift under heavy right foot. Codes po729, 735 and 765 come up. After a couple of ignition cycles, everything is back to normal until it happens again. Spoke to ATS hoping that it would be a simple vb swap, but they're saying possible clutch damage. Some yt searches indicate that it could be as simple as a bad tcm.

What I can't seem to find is anyone that has the codes come n go like mine. Anyone experience this ?

 

[Burla]

Hard shifts early in gears or late? The issue is the Cummins, it can chew up oem rfe's. Makes the decision what to do harder, replace VB and solenoid and update and upgrade everything, but if the clutch is burnt it is all for not. If it was early hard shifting I might drop a cleaner in and see what happens, auto rx is the stuff I used. If it is late hard shifting 4th,5th, or 6th only, I might try the vb route. Just one mans opinion.

 

[Caboverbob]

The hard shifting that is causing the codes is typically experienced when passing or resuming 65+ mph after slowing for traffic. It may happen if I left a stop light/sign aggressively, but I don't usually drive like that.

Todd

 

[Burla]

Valve bodies are plug and play, if you can drop the pan and you have a torx bit 25 you can swap your valve body. The over drive and accumulator pistons are notorious. If you fix it, you might avoid a rebuild transmission. They have valve bodies you can buy already done, or get a kit.

Product Overview: ATS 68RFE Valve Body and ATS Co-Pilot

Clint Cannon, President of ATS, describes the inherent weaknesses of the 68RFE (545RFE, too) valve body. This is a comprehensive overview of the numerous pro...

youtu.be

 

[mtnrider]

Is the truck stock or tuned in any way?


.

 

[DodgeDude99]

Valve bodies are plug and play, if you can drop the pan and you have a torx bit 25 you can swap your valve body. The over drive and accumulator pistons are notorious. If you fix it, you might avoid a rebuild transmission. They have valve bodies you can buy already done, or get a kit.

Product Overview: ATS 68RFE Valve Body and ATS Co-Pilot

Clint Cannon, President of ATS, describes the inherent weaknesses of the 68RFE (545RFE, too) valve body. This is a comprehensive overview of the numerous pro...

youtu.be

Valve bodies are plug & play from a mechanical aspect but a quick relearn must be done after install. The 6 valve body to case bolts are an M6 flanged head and not torx, the valve body halves are torx.

 

[TorqueWagon]

Hard shifts early in gears or late? The issue is the Cummins, it can chew up oem rfe's. Makes the decision what to do harder, replace VB and solenoid and update and upgrade everything, but if the clutch is burnt it is all for not. If it was early hard shifting I might drop a cleaner in and see what happens, auto rx is the stuff I used. If it is late hard shifting 4th,5th, or 6th only, I might try the vb route. Just one mans opinion.

I agree with Burla. My Cummins just overpowered the trans and eventually burnt it up at 200k miles. Had the trans completely rebuilt with upgraded clutch packs, higher line pressure, a better torque converter and a few other things to "beef it up". Added a trans cooler. Added a Larger pan with cooling fins. typically runs 165 degrees on a 80 degree day towing my 26ft travel trailer. Ive never gone much over that, but if I ever would reach 200 degrees, I would pull over and let it cool. Fluid starts breaking down above about 215 degrees. Lastly, put in an Edge CTS3 performance monitor so I could watch TFT (trans fluid temp) - I can also watch when the torque converter locks up. I like to modulate my throttle to keep it locked as much as possible since that makes a big difference on trans fluid temp. Best of luck to you!

 

[Burla]

I agree with Burla. My Cummins just overpowered the trans and eventually burnt it up at 200k miles. Had the trans completely rebuilt with upgraded clutch packs, higher line pressure, a better torque converter and a few other things to "beef it up". Added a trans cooler. Added a Larger pan with cooling fins. typically runs 165 degrees on a 80 degree day towing my 26ft travel trailer. Ive never gone much over that, but if I ever would reach 200 degrees, I would pull over and let it cool. Fluid starts breaking down above about 215 degrees. Lastly, put in an Edge CTS3 performance monitor so I could watch TFT (trans fluid temp) - I can also watch when the torque converter locks up. I like to modulate my throttle to keep it locked as much as possible since that makes a big difference on trans fluid temp. Best of luck to you!

in case you never seen it, redline c+ is line 2 and 5, and what most people use is line 1. It isnt about brand, but science. Redline's base oils work best in the extremes, hot and cold. I did a drain and fill on my rfe, it took 8 quarts, put the metal thread upgrade and will put synthetic filters and do it again this summer.

 

[06 Dodge]

The hard shifting that is causing the codes is typically experienced when passing or resuming 65+ mph after slowing for traffic. It may happen if I left a stop light/sign aggressively, but I don't usually drive like that.

Tod

I would give Dave Goerend a call: https://goerend.com/

 

[jejb]

Is the truck stock or tuned in any way?

Good question.