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2017 68RFE Transmission Question

7.1K views 28 replies 10 participants last post by  brendog84cj8  
#1 ·
I looked and was unable to find an answer to my question

My RPM, just prior to an up shift, will raise 200 or so, as if the transmission is free wheeling for a split second prior to shifting to the next gear.

So from say 2-3 or 3-4 or 4-5, doesn't seem to do it from 5-6. And it isn't all the time.

The truck has just shy of 5000 km (3000 miles) on it and this is a new thing.

Anyone have any thoughts on this please?
 
#2 ·
Sounds like the torque converter unlock, shift, relock sequence.

Have you research that topic?


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#3 ·
I will add those to my search perimeters.

Another thing that I noticed this morning, it was 10 degrees C (50 F) outside, was that immediately upon starting my truck, the transmission temperature gauge showed 1/4. Seemed odd to me?
 
#6 ·
So I just ran outside and checked the temps

haven't driven the truck since 7am (it's now 12:42 here) and it read 18C (64f) immediately on the gauge. It is only 10c (50f) outside right now

Do these have some kind of preheater in them?

that seems peculiar to me?
 
#7 ·
Takes significant amounts of time for 17 quarts and all those mechanical parts to cool. 14 degrees above ambient is that much especially compared to actual operating temps. Try it again 24 hrs later.
 
#9 ·
After playing with the gears and TH I have discovered it is only between 3-4 and when TH is active. It is exactly what is described as flare up.

I wonder if Dodge will release an update for the programming to rid the truck of this as there is a tune out there that addresses it
 
#12 ·
Another question

Is it normal for the transmission to just drop to an idle as one is slowing down as opposed to the transmission down shifting?
Your motor and tranny will turn at wheel speed only while the torque converter is locked. As you slow down, (foot off the accelerator) at a certain point the TC will unlock, so yes the engine can just drop to idle speed.
 
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#13 ·
If you want it to down shift you will need to run in Tow/haul mode and it will downshift(if certain perimeters are met) or manually down shift it. On these 17's with the 3:42's they seem to go down to idle almost as soon as you let off!! I hate these 3:42's!!! Going to 4:10's ASAP so I will have somewhat of an exhaust brake while everyday driving!!!JMO
 
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#15 ·
It seems the gearing is not the right fit for these trucks. My last truck had 4:10's and it seemed to do what it was meant to do.

The dropping to an idle at 60-70km/h is ridiculous. A person isn't supposed to drive down the highway with their clutch pushed in, why is it ok for an automatic to allow the vehicle to freewheel.

I drove a 17 F350 Monday, it didn't freewheel and it down shifted as I was coming to a stop. But, the exhaust brake didn't seem to do anything, so who knows.
 
#16 ·
Agreed!! The 3:42's affect a lot on these trucks and I know Ram put them in for fuel mileage. But like you I came from a 4:10 truck that performed exactly like I wanted it to. Seems I am always on the brakes in this17' because when you let off in 6th gear the RPM's drop down below 1000 which is below where the exhaust brake stays activated!!! In my 12' with 4:10's I could ride the exhaust brake down certain hills I travel and now I am riding the brake pedal!!! Going to add the center console shifter to this 17' so that I can down shift it easier. (For Starters)
 
#19 ·
Is there anyone able to confirm for me that their manual gear selection will change the gear in the transmission.

Today again, I manually down shifted from 4-3 at 30 mph, and nothing happened. It showed on the dash that the selection was in 3rd but that the transmission stayed in 4th.

now if I step on the accelerator briefly it will shift, but if I hold a steady throttle, notta.

thank you
 
#22 ·
Is there anyone able to confirm for me that their manual gear selection will change the gear in the transmission.



Today again, I manually down shifted from 4-3 at 30 mph, and nothing happened. It showed on the dash that the selection was in 3rd but that the transmission stayed in 4th.



now if I step on the accelerator briefly it will shift, but if I hold a steady throttle, notta.



thank you


It won’t shift regardless of the gear selection on the manual selector until certain conditions are met. The truck will override you.


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#20 ·
It won't shift under load. Click down a gear, let off the throttle, and viola


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#21 ·
I gave this a shot on the way to work today and still no go with the downshift

The only way I could get it to shift down was by pressing the accelerator peddle.

Is this just the way that this transmission is?
 
#23 ·
My 17' will downshift as Cumminsthanstrokin stated, shift down and let off the throttle slightly!! I manually shift my truck a lot with the current 3:42's and it does ok. If yours will not down shift by doing as stated maybe you need to get your dealer to try a Trans. relearn??
 
#28 ·
Because your dealer doesn't know what he's talking about. The only thing that should inhibit a manual downshift (assuming the trans isn't in limp-in or something) is if you would over-rev the engine. Fourth gear at 40 mph will not over-rev the engine.

Again, have them take a scan tool and monitor present gear, target gear, and ERS gear. If you tap it down so that ERS Gear = 4, then Target Gear should immediately change to 4, it should downshift, and then Present Gear should also read 4 after the downshift.

If ERS Gear goes to 4 and Target Gear stays at 5 or 6 (at 40 mph), I'd say you have a bad PCM.