[Oliveman]

I have had two Reduced power / Check engine episodes so far on this new truck. Both times were pulling 3000# travel trailer, in tow mode, on 6% grade, in cruse control at about 65 miles per hour. Limped into dealer. Three days of diagnostic only to say "Soft failure"
I believe it is an issue of towing in cruse control as I no longer tow in cruse and I no longer have Reduced Power issues. But from looking over many threads, Reduced Power is a common issue

 

[Burgess159]

I suppose something could have been getting warm on the truck, maybe the transmission, so it decided to do that. As the cruise was trying to hold it at a set mph/ rpm. Did you have tow/ haul engaged while doing this or not? If you weren't, the truck was probably in 6th gear or trying to get to 6th, and maybe it got too warm and gave up. Putting the truck in tow/ haul limits it to 5th gear I believe.

I dunno, just speculating.

 

[7.62x39Colorado]

I’m thinking transmission or tcm.

 

[bigoilbob]

I have had two Reduced power / Check engine episodes so far on this new truck. Both times were pulling 3000# travel trailer, in tow mode, on 6% grade, in cruse control at about 65 miles per hour. Limped into dealer. Three days of diagnostic only to say "Soft failure"
I believe it is an issue of towing in cruse control as I no longer tow in cruse and I no longer have Reduced Power issues. But from looking over many threads, Reduced Power is a common issue

We can empathize, sincerely. We can all imagine your frustration with this, whether it has happened to us or not. As one more data point, never happened to us with over 15K miles of towing, all harder than what you describe. We HAVE lost our exhaust temp sensor (not the proper name for it), which lost us TT mode, which lost us 3 days to get the part and get it fixed on warranty. But we just camped, drank, swam, which made it part of the adventure.

I don't think it was the transmission. Even if it was smokin' hot, you didn't work your truck that hard. Especially if you were in TT mode. Of course I'll stand corrected if you come back to tell us that you saw trans temps above ~230F. I don't think it was your cruise control. Why would it be? I DO think that your dealer diagnostic is weak. Is there really a code called "soft failure"? Not rhetorical folks, I'm aksin. Lots of you know these codes. I don't. But I can't imagine any reduced power event not being traceable to an actual operational condition that you could avoid or remedy....

Oliveman, since you didn't mention a trans temp, I'm thinking that you're not periodically clicking thru your info buttons when you tow heavy. If not, it's a good habit to pick up...

 

[scarfile]

Happened to me exactly. Dealer replaced wiring harness connectors and rerouted some cables.
Problem solved.

 

[TruthSeeker79]

I had trouble code P233 I believe, it said “over-voltage at turbo booster” turned out, it was a fouled air filter!!! Overlooked the air filter since I perform all my own maintenance. I tow a 7k lb duel axel tool trailer every day. With the tools, I’m definitely pushing the max haul of 7600 lbs. Trans Temps run real high close to 230^ F after an hour haul. I turn the heat on max when I hit 215^ F. Hate the weak heat displacement mechanism with this truck, but other than that I’m satisfied with my Z71

 

[bigoilbob]

I had trouble code P233 I believe, it said “over-voltage at turbo booster” turned out, it was a fouled air filter!!! Overlooked the air filter since I perform all my own maintenance. I tow a 7k lb duel axel tool trailer every day. With the tools, I’m definitely pushing the max haul of 7600 lbs. Trans Temps run real high close to 230^ F after an hour haul. I turn the heat on max when I hit 215^ F. Hate the weak heat displacement mechanism with this truck, but other than that I’m satisfied with my Z71

Does your coolant get hotter as well? If not, then I doubt that turning on the heat is helping your trans temp. This is a liquid/liquid trans cooler, right? From my experience with trans temps in the 210-220 range, it seems like the liquid rates thru the cooler (coolant, trans fluid, or both) are low. I have gotten up to 220, towing in the mountains, and then had to stop for 10-15 minutes for construction. I shift to park, watch trans temps. It takes that long to drop maybe 15F, with coolant that never got hot.

If I'm getting this wrong folks - and I might be - please correct me

 

[TruthSeeker79]

Does your coolant get hotter as well? If not, then I doubt that turning on the heat is helping your trans temp. This is a liquid/liquid trans cooler, right? From my experience with trans temps in the 210-220 range, it seems like the liquid rates thru the cooler (coolant, trans fluid, or both) are low. I have gotten up to 220, towing in the mountains, and then had to stop for 10-15 minutes for construction. I shift to park, watch trans temps. It takes that long to drop maybe 15F, with coolant that never got hot.

If I'm getting this wrong folks - and I might be - please correct me

Are you then saying, that in part the cause of my trans temp so high could be low on trans fluid?

 

[bigoilbob]

Are you then saying, that in part the cause of my trans temp so high could be low on trans fluid?

No, just that the flow rates of either coolant and/or trans fluid thru the liquid/liquid cooler SEEM TO ME TO BE so low that it takes quite awhile for the trans temp to drop after we have increased it. Again, one man's opinion. Anyone with better knowledge, I urge them to set me straight.

 

[Leo Whitlock]

No, just that the flow rates of either coolant and/or trans fluid thru the liquid/liquid cooler SEEM TO ME TO BE so low that it takes quite awhile for the trans temp to drop after we have increased it. Again, one man's opinion. Anyone with better knowledge, I urge them to set me straight.

I have noticed the same thing, transmission doesn't cool down very fast even when coasting downhill.

 

[oak1971]

Do our trucks come with an air to oil trans cooler or is a coolant to oil concentric oil cooler in the radiator tank? I used to test both types when I worked at Modide Manufacturing in the calorimeter lab.