2019 Downshift issue

Hi everyone!
The other day I noticed that while driving with the cruise set, the truck will downshift to 5th when coming up from an underpass and will not shift back to 6th when the road flattens out again. I have to turn the cruise off for it to upshift, then on again and set it until the next underpass. It's pretty annoying.
Is anyone else having this problem?
2019 TRD OR DCSB with 1900 miles.

 

Unfortunately sounds pretty normal to me...

 

It's not a "problem". The delay is there to prevent the transmission from constantly shifting up and down when you're going over hilly/up-down terrain. I like that it does this, personally.

 

Both 5th and 6th are overdrive ratios. Just let the truck do its thing.

 

Did it do this before the lift, wheels/tires?
Did you re-gear?

 

Mine did "exactly" what you say.....checked tranny...Added 1 1/2 liters of juice and it stoped doing that and now it runs "normal"....

Check it properly.....None of this..."we put in on the puter and it's good". Have then physically or do it or do ityourself.

 

My 2018 was rather shifty and would hang on to a low gear for what I thought was too long, especially when hitting level ground after climbing a hill. It started getting better at 5,000 miles and is no longer a problem at 11,000 miles.

 

I did not notice it before the lift, but I wasn't really doing any long drives in it. I only had 400 miles on it when i put the OME lift on. I did not regear as I went to 265-70r-17 and didnt think it justified regearing with that small of a tire size increase.

 

I will tell them of the condition and make sure they check the fluid level at my first service.
Thank you!

 

lol mine still does it and its got 6400 miles even with the OV tune. i just stopped using the cruise control. deaer said fluid was fine. at the 10k service i will have them recheck it. mind you mine is lifted and bigger tires. good bye MPG.. down from 19.5 to 15.6 on a good day. Im about to put 1500 miles on a road trip so we'll see how it goes. pretty annoying either way for a truck.

 

The "delay" persisted for several miles on flat ground. I understand a few seconds or something, but several minutes seems excessive to me.

 

I'm getting about 17.5 avg with the lift and roof rack. 16 when I'm carrying my canoe, but I only do 60 when it's up there.

 

Several minutes seems abnormal.

Sometimes even a slight incline or headwind can be enough to prevent it from shifting. Mine usually upshifts 10-15 seconds after the terrain flattens out or starts to go downhill.... not minutes.

That being said, these trannys are pretty bulletproof with few if any instances of premature failures, so I doubt there is something wrong with yours. It might just be that the terrain is not as flat as you thought, or you were running into a headwind, or maybe you have mods that increase rolling resistance?

 

It very well can, I like the engine/transmission combo, but it is a little low on torque. The parameters set, are going to up or down shift when a certain level of throttle input is needed. Think of the old days, when the cruise was manipulating the gas pedal. If there's enough resistance (wind, weight, drag, improper gearing, etc etc etc) the amount of throttle input needed to maintain speed, is being read by ECU and its telling transmission not to upshift, until less throttle input is needed. If it did upshift too soon, the amount of throttle input would increase, thus calling for a downshift again, so its going to hold that gear, to prevent back and forth.

 

You will get resistance to check it physically. The computer apparently is not accurate... You might have to pay them to check it physically as it takes about 3/4 hour....…… If you decide to go that way, tell them you'll pay IF it's full and Dealer pay if it's low. Might cost you a couple hundred. My dealer wanted $150.00 to do it, so I said thanx and did it myself...

EDITED.

 

Update:
I have discovered that if you give it a little gas for a few seconds and let off, it will shift back into sixth.

 

Mine doesn't do it anymore, manual took care of all that nonsense.

 

Mine acted like that from new. While using cruise and it shifting down to maybe 5th...….go over the hill and it hesitated half way down the other side of the hill.

I filled the tranny and all is good..! She up shifts as soon as we top the hill.

She was 1 1/2 liters low.

 

You're better off running S-mode in 5th all the time unless you plan on driving 85+ mph. 6th is essentially a downhill gear on these trucks. Interstate driving with any elevation change with cruise on is a sloppy mess if you let it shift into 6 at 70 mph. Try it.