2013 68rfe TQ Slip 6th Gear

[DArndal]

My 2013 Ram 2500 with 68rfe 3.42 will slip TQ in 6th. Truck has done this unloaded recently several time while climbing grades in 6th gear. The truck jerks/hesitates for a split second. The RPM's never budge. So I think the TQ is slipping. Shift the truck to 5th and it won't slip. Anyone else have this transmission do this with only 10000 miles?

 

[Bob4x4]

If thr rpm doesnt change it is not slipping

 

[PKnight]

Check for fault codes. If there is slippage it will throw a code.

 

[DArndal]

I've checked for codes with my scanner and nothing. When it hesitate/jerks sometimes you can hear the driveline backlash. I never hear any change in motor or RPM sounds. It doesn't shudder it just jerks. It only happens when climbing grades usually with a head wind. It feels as if the TQ slips for a split second and grabs again. It happens more often going slower, 50-60 mph. It has never happened going faster like 70. Every time it has happened I drop to 5th and up the RPM's and it won't slip. It's a bummer because the nearest RAM dealer is 2.5 hours away.

 

[DArndal]

Another way to describe what I feel it like running over something in the road. The first few time it happened I was looking in my rear view mirror because I thought I ran over something. The truck bumps/jerks for a split second

 

[transe]

Sounds more like an engine issue to me (than a trans or converter problem). Sometimes engine torsionals will slip the Torque Converter Clutch (TCC), typically at heavy throttle and low engine speeds, but this usually causes a significant shudder (like running over chatter bumps) that continues until you back off the throttle, or downshift to a lower gear (to raise the engine speed). It's typically not a single bump or jerk. So I suspect maybe a momentary interruption in fueling. You might check your fuel injector wiring for a loose connection on one of the injectors.

 

[DArndal]

Thanks for all the insight. I really think it is the Torque Converter Clutch because the motor never studders and it perfectly smooth. I agree with TransEngineer about it should shudder until you back off, but just bumps. It always heavy throttle low engine speeds. I called Carson City Dodge and they scheduling me an appointment, hope they can fix it.

 

[RVTRKN]

My 92 Dodge 318 Magnum V8 Dakota would do that, but it would try to downshift then upshift in a blink of an eye, while climbing grades. I just kept my foot out of it or downshifted. I'm not trying to start a feud on rear ratio's, but your 3:42 and climbing a grade might be part of the issue, kind of like what I described with my Dakota. So what were your RPM's when climbing, could you have hit the downshift point, but it went back into 6th?

 

[DArndal]

Never thought of it trying to down shift, but maybe that it why I don't feel a shudder just a jerk/bump. It happens under load with the tach around 1500 RPM's in 6th gear 65mph. If I shift with the paddles to 5th RPM's raise to around 2000 RPM's. My buddy who I sold my trusty 5.9 to likes making fun of my new truck. Off to dealer is goes, I hope they can find some answers.

 

[Missouri Mule]

Your in to high of gear for going up hill. Need to down shift. I would think at 1500 rpm in 6th gear going up a hill you would be lugging the engine. But I'm use to my Mule and Freightliner (Moose) and going up small/medium hills in Florida and I am running 70 in my overdrive gear. Mule has a better overdrive gear than Moose ( Mule has been thru the TN Mountains quite a few times and a Killer hill on I-70 in Missouri. I usually hit 1000 degrees trying maintain 70 mph on that hill. Not really that high just steep).

 

[RVTRKN]

1500 RPM is too low for climbing grades, loaded or unloaded, even at 65 MPH. Your torque curve is still up there but not the HP. Now add the equation of the 3:42 ratio, and you have a truck feeling like its loaded. I'm willing to bet your confusing the trans, but your trans is supposed to be able to learn, maybe it will go away in time. Keep in mind that your CTD has a sweet spot in RPM at @ 1900-2100 RPM and if it can run at a lower RPM cruising, that doesn't mean it can climb at that lower RPM. With out a Pyrometer, I wouldn't lug that CTD, it can cause high exhaust gas temperatures. The best RPM for your CTD climbing is somewhere @ 2100-2500, keep your RPMs up and see if it does it again. My 3:73 ratio, limits me while loaded at @ 15K GCVW and in rolling hills can be a nuisance, due to my manual transmission, having to constantly downshift and upshift manually. I'm not a fan of the 3:42 ratio, but for unloaded driving its a great ratio, just keep in mind to keep your RPM's up in climbing grades no mater what gear its in.

On edit, try keeping it in tow haul mode when climbing.

 

[Sticks]

Remember - Redline is what Cummins calls "High Idle". You won't hurt it.

 

[Newt]

With a stock 6.7 w/6 speed auto, you can't hurt it. The computer won't let it be hurt. If it needs to downshift, it will. If you have an Edge CTS, it helps you understand how the engine operates.

Newt

 

[RVTRKN]

I wonder how long the drive train will last including the transmission, if that scenario keeps up. The truck needs to be in tow haul when climbing grades empty or not, to eliminate the hunting of gears due to the 3:42 causing the truck to lug. 1500 RPM in sixth gear climbing is not good for the CTD, regardless of computer capabilities.

 

[Joseph Donnelly]

I'm not sure what the issue is, but my 2013 pulls happily at 1500, and the Aisin downshifts if pulling a trailer uphill, then upshifts near the top of the hill. I only use tow-haul mode when pullig a trailer. I am amazed at the wider power range and general capabilities of the 6.7 vs. my 5.9. I had the 2004 bumped to more power than the 6.7 would give on the dyno, but the 6.7 is much happier than the 5.9 at lower rpm. Part of the reason could be the 408 cubic inches vs. 359.

 

[RVTRKN]

It may feel that way because of the higher stock HP and TQ, but with the bored and stroked 5.9, it works harder to achieve the same results. Tow haul is doing what its designed to do, the Aisin also can take the low end torque better than the 68rfe when not in tow haul and climbing a grade at 1500 RPM.

Joseph, do you have a pyrometer installed yet to see what your EGT is, if you were try to run at 1500 RPM in sixth on a grade empty? I believe the trans is hunting for the correct gear for DArndal's truck. As mentioned prior, I had a trans do that very same scenario while climbing grades trying to maintain my speed in 4th which was top gear for a 92 318 Dakota.

 

[Bug Out]

I tow at max GCVW 25K with my 5th wheel. On flat ground, no big headwind at 68-70 MPH, it rolls along in 6th fine. The minute it hits a hill, it down shifts to 5th and keeps rolling. I use 5th all the time in town and 6th on the highway only over 55 mph. No problems yet..(except for the TCC un lock flare that drives me nuts)

 

[RVTRKN]

Maybe thats DArndal's issue, maybe its the TC?

Bug Out, whats your rear diff ratio?

With my Dakota, I suspected the TC, I'm not familiar with the operation of it except it could give you an in-between 3rd and 4th. I don't want to describe the operation of the TC, I'll let the experts here do that. I never liked automatic's and it was the first reason why I chose the G56 (what a mistake) the second reason was the NV5600 I had in my 2500 is so awesome that I didn't think the G56 would be that much worse, being a Mercedes Benz built trans.

If you have the 3:42 ratio, it can cause the trans to hunt for the right gear, like I have to constantly shift between 5th and 6th when in rolling hills with my 3:73 ratio and towing at GCVWR. The 3:73 was chosen for the city traffic MPG, that I rarely do today but was planed on when ordering my truck.

 

[DArndal]

I only drive my truck in Tow/Haul with exhaust brake. It has know become part of my starting the truck routine because Tow/Haul shift so much better. I have never had the slip/bump/jerk when towing my 10k trailer, it will always downshift when needed entering onto grades. Its only happens empty climbing slight grades 3% most the time with a head wind running empty (I'm in Tow/Haul). Feels like someone kicks the back of my seat really hard. The motor never spudders and sounds smooth the hole time. The truck will just have a split second loss of forward power. 1500-1600 RPM's doesn't sound luggy at 65mph and has the ability to accelerate. I agree 2000 RPM's in 5th the truck climbs with lots of power and the slip/jerk/bump has never occurred in 5th. It's Carson City Dodge job to figure this out. I talked with the trans tech there and he thinks its the TQ slipping.

 

[sag2]

Ask them to get a data recording of the event happening. That will tell them what it's doing.