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Need Help! 14 Ram Surging at stoplights!

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Cabin filter change,2016 laramie 3500

transmission temps and vibration

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Gentlemen and Ladies,
You guys have always been fabulous so I'm throwing this one out for your feedback. My 2014 (non-Aisin 6 speed auto) started to do some strange stuff a few weeks back. In the morning an the way to work, the truck will sit at a light and the RPMs will surge up and down like a "lope" by a couple hundred RPMs...can't really say how many because the tach barely moves. The RPMs just bounce. It feels like the TC is maybe locked a bit and then releases...I know what that feel's like because I used to have the TC manual lock switch on my 06 and sometimes would forget to unlock the TC until I felt it bogg the engine.
Anyway...no codes are thrown and by the time I drive 20 miles on the freeway to work, it stops being weird and drives fine. I think it is something with my TC because I can put it in PARK and it does not do it. It seems to be more pronounced when I drive in TH mode with the EB on in either mode.
I change the AT fluid/filter every 45K and so the fluid is pretty new...maybe 8k on it. Last week I towed my 11k pound 5er up to the mountains on Labor Day and got into traffic (standstill) at the bottom of a pretty steep grade going into Payson Az and had to basically crawl in 1st gear all the way up. My AT fluid got up to around 209 degrees and came back down to about 203 for the trip according to the digital gauge in the dash. I'm not sure how accurate that is but I'm not sure where the breakdown point of the AT fluid is but it does not smell burnt and isn't dark when I checked it on the trip.
So...it was behaving strangely every once in a while and now it has done it the last 2 mornings. Anybody have an idea where I need to start with this thing? Is there a switch that controls the TC lock and unlock that I can replace that is accessible? How reliable are the TC on these Mopar 6 speed AT's? In my 06, I just went with a billet Goerend unit to avoid issues but this one has gone almost 95K miles without trouble.
Sorry for the novel. Thought more info was better than less.
 
Does the truck try to pull thru the brakes on pavement? Spin the tires on gravel when the surge happens? A 69RFE holds the TCC off with fluid flow thru the converter fed from the spin on filter in the reservoir, if the the seal is broken on the spin on filter at idle they will surge as flow drops and the TC engages. Some filters had bad seals that would displace and\or the spin on filter base would crack and leak. Something to checkout if you feel the TCC is the root problem.

Other root cause could be from the MAP sensor dirty from ingesting oil vapor from lousy PCV design, asphaltene build up in FCA or injectors, failing rail PRV. A good cleaning of the fuel system may be in order you do not religiously use and additive package with cleaning properties.

AT fluid at 209 is not even close to worrying about, about the middle of the operational range for ATF+4.

There are several builders for 68RFE units, not as easy as the 4XRE units though as the 68RFE has some built in failure points that need to be addressed if you use it hard. A billet cover TC, replacement VB separator plate (or full VB with updates), and good tuning will make them a totally different animal. The rest of the updates are internal replacing weak stamped pieces with billet and adding clutches where needed. A good update path is separator plate, raised pressures, and tuning.
 
Thank you Cerb...the spin on filter will be my first stop. This morning, all was well. It seems like that is the pattern. It will act up and then if I drive it over 20 miles to work, it will behave for a while (weeks). I got worried when it acted up 2 days in a row but then I remembered that I did not drive it a long distance on Sunday and it kind of carried over. I'll also check the MAP sensor...I do use Power service intermittently as I tow.
Thank you for the help!
 
I saw this problem recently on a Duramax and it was the fuel rail pressure sensor. I know, different engine but similar symptoms. He had no codes just surging.

Also, check for any potential places where you might be sucking air. That will definitely cause surging. Fuel lines, filter, etc.
 
Also, check for any potential places where you might be sucking air. That will definitely cause surging. Fuel lines, filter, etc.


Since the LP system is under 7-9 psi there isn't going to be any sucking air as a rule. About the only way that happens is if the draw straw gets a hole in it and fuel level drops below the breach. Possible just not very probable.
 
My surge at idle when cold (and outside air around 50degrees) is back with a new friend. The truck has now developed a hard miss at idle. Give it some throttle in gear and the miss clears up until you come to a stop. Having done the rail pressure sensor and regulator I’m thinking I’ve got a bad injector. No codes though. Anyone know where to get good injectors? Someone on eBay has a kit including the valve cover/ harness gasket and the cross over tubes. Bet are they real Bosch injectors?
 
Buy BBi - worth every Cent and you know what you get.
Doesn't matter if you get the remans or the new ones, both are top notch.
 
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