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Cruise Control 'surging'

The OTA update is for the UConnect system which, to my knowledge, shouldn't affect the ACC system.

i thought so too, but i am absolutely 100% certain the ACC is driving differently, no longer making passengers car sick, something changed. ill try again tomorrow.
 
i thought so too, but i am absolutely 100% certain the ACC is driving differently, no longer making passengers car sick, something changed. ill try again tomorrow.

I haven't installed the update yet, so I will grab a bunch of telemetry with the Banks iDash before installing the update. I will compare the results after the update.
 
Just drove from Florida to Wisconsin, Uconnect updated overnight at a stop.
Cruise Control still can't hold a steady speed on a flat level road, constantly accelerating and decelerating.
ACC still brake and accelerates harder than necessary.
 
I’ve had my 2019 PW for about two weeks now. I drive 95% highway and always use cruise control and have noticed this surging (normal cruise and adaptive , with and with out mds on). It seems to run about 1kph above setting and when it hits set point will then surge back to 1 above SP.
Did you ever happen to find a resolve for this? I have brought it to a couple of different dealerships and no resolve. FCA is terrible and won't help. Ram just replies saying it's a characteristic of the truck.
 
Did you ever happen to find a resolve for this? I have brought it to a couple of different dealerships and no resolve. FCA is terrible and won't help. Ram just replies saying it's a characteristic of the truck.
My 19 ended up flattened when a large tree fell on it during a storm! I replaced it with a 2020 PW! The 20PW does the exact same thing. (Normal cruse, MDS off) it seems to be that as your set speed drops slightly, it over compensates on throttle increase. I haven’t bothered even asking the dealer!
 
I get that happening when ACC is on the furthest setting and someone changes lanes much closer in front of me. I like it at 2 bars anyway and it behaves normally there.
 
i thought so too, but i am absolutely 100% certain the ACC is driving differently, no longer making passengers car sick, something changed. ill try again tomorrow.
I just had the Uconnect recall flash done last week while my truck was in getting the bed step recall done. Drove ~200 miles round trip today with the ACC on the whole time and was very surprised that I didn't notice any surging. Fingers crossed that the update included the fix and it wasn't just a fluke.
 
Mine was better after the flash but still WAY more aggressive than it should be. The sucker slams on the brakes when just letting off the gas would do the job. It is like it is all or nothing. Also, I had to turn off the collision braking. It would activate during turns when there are barriers up or occasionally for no reason. Scares the living hell out of me. That "emergency braking" for no reason is going to cause an accident.
For most cars these functions are not binary (on or off). RAM needs to work on the feedback loop and the gain on these things. The ACC will be useless when I am pulling a trailer, I do not need the truck to jack on the brakes aggressively.
 
I have less than 400 miles on new 2021 HD, no ACC. When resuming CC, truck sped up, rpm to 4500 with no addition speed. Brake cancel did not resolve, cancel on wheel, no resolve. Turn off CC still no resolve. Pulled to the side of road, turned off truck, let it sit a couple and when I restarted engine, it ran as regular. I did not use CC for remainder of trip.
 
My 19 does the same, surges while CC is on. feel like its lightly hitting the brakes on highway on a very small hill instead of letting off accelerator
 
On my '21 3500 with 6.7 my cruise is very annoying. Doesn't matter if I have the regular cruise or adaptive cruise on. What it does is it will accelerate 2 mph over the set speed when going up a hill and when it crests the hill it slows it down to 2 mph below the set speed. That's a 4 mph difference and you can see it upsets drivers behind me as they will tailgate me when it slows down. On flat ground everything is fine, it's just climbing any hill.
 
I don't have the latest updates from the dealer. I should get that done. That's staring to bug me too - that I have to go there for something the computer industry has been using the internet to do for yeyears.
I know a couple people with Tesla's and their cars update thru wifi when parked at home. Some updates include a power increase too. I would figure if Tesla can easily do it so should most other manufacturers as well, especially the "big 3". You would think it would save the manufacturers a ton of $'s too without having to pay the dealer to do warranty updates
 
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