While it doesn't full-on engine brake when I slow down, there is definitely something going on. I cannot smoothly slow to a stop without feeling the transmission downshift and grab a little bit. Seems to be when going from 4th to 3rd and then 3rd to 1st. Is this normal behavior? I feel like gently and smoothly slowing down is simply not possible in this thing without a little bit of a subtle jerk or 2.

I came from a 2012 Sierra, and the 6 speed in it was smooth and predictable. While there is nothing majorly wrong with the 10 speed in my new XLT, it just feels unrefined. Is this just how they are or what?

 

check out this thread
https://www.f150forum.com/f129/rough...ission-505009/

How many miles on your truck?

 

about 1300.

 

Alright so I went down the 10R80 rabbit hole after reading that thread. My truck had about 500 miles on it when I bought it (was driven from another dealership), so it sounds like maybe resetting the adaptive learning tables with Forscan might be a place to start. Mine doesn't have any of these super-hard shifting issues I've read about, so I'm hoping that will do the trick. I also pre-ordered the Livernois tune, and it sounds like a good tune can clean these things up too, so I'm going to see how all of that goes before I complain to the dealer.

 

So I cleared out the learning tables with forscan, and the transmission mostly feels fine now. I think part of it was me figuring out how to "teach" it. Most of my driving has been city driving, so im generally pretty easy on the throttle, and I noticed after the first hundred miles or so, that the transmission was shifting fairly firmly for the amount of throttle I was giving it, and that if i gave it much throttle at all it would hold gears and shift hard, definitely making for some awkward transitions pulling in and out of parking lots etc. So it then occurred to me that since i had been mostly creeping around town up to that point, that by even giving it moderate throttle, it probably thought I was driving it "hard" and needed to hold gears and firm up the shifting. So what I've been doing since then is making sure I vary the throttle more even when I don't need to. I'm definitely not gunning it everywhere, but I have been giving it more throttle on acceleration here and there. Now, when I creep around town, it shifts smooth as butter, I'm assuming because it recognizes that I'm driving it easy vs before where driving easy was basically as hard as I drove it.

Anyhow, mostly anecdotal, but I thought I'd update.

 

Always appreciate when people here follow up like this, glad it is showing some improvement for you.

 

One thing to consider is 10! Gears
it shifts a lot it took a while to get used to it.
my last truck was a 08 GMC Sierra with a 4 spd

 

Well, I had gotten used to the 10 gears part due to being in both 2020 KR and 2020 Silverado rentals for a combined 2 months. I don't remember even having thoughts about the Silverado's transmission (I was in it for about a month before the KR), I had a Sierra with the 6 speed for several years prior, and the Silverado trans just seemed like a natural progression. The KR seemed a little touchy, and so does my 2021. Really I feel like half of the issues I've had with it are throttle tip-in related as much as anything. I can be trying to creep out of a parking lot onto the road, and rolling over the gutter might shake the truck enough to cause me to give it a tad more throttle, and cause it to surge, and that's even while trying to be conscious of it. Light throttle seems way too touchy to me.

All that being said, it's behaving a lot better after having the tables cleared 200 miles or so ago. I'm hoping an eventual tune will smooth out any other complaints that I have.

 

Came from a 13 1500 GMC SLT with the 6 speed in 16 to a 16 501a 6speed,then to a 18 max tow, 19 max tow and now a 21 302a Power boost with towing.

None of these trucks shifting has been ever as bad as the 13 WTF just happened shifting pattern it had. Passengers would turn and look with what just happened and the answer was its a wonder shift. And for those who complain about Fords shifting and dealers telling you oh that's normal well GMC does it also.

Mercury's, Lincoln's deserve silky smooth shifts, when your in a truck one needs to know.

Came from the 460 Ford Truck world and when you didn't feel the transmission shifting things were about to go bad. Hard shifts back then things are working correctly.

Turn off the the numbers and drive the truck. A friend had the same issue with his new 98 F150 with the 4 speed oh it shifts to much, he still is driving that truck today.

Rabbit holes are for rabbit's which in turn are a prey animal for the predators.
__________________________
21 XLT 302a PB with towing

 

I'd bet good money that you're confusing the slip-yoke clunk that range of GM trucks were famous for, for something the transmission itself was doing. Fortunately, once you got a feel for the situations that cause the clunking, you could mostly avoid it. Why? Because those transmissions were predictable enough that you could pretty accurately control when/how hard they shift with throttle input, and minimize the clunking in the situations where it typically happened.


"It's a truck, get used to it" might be fine for people who don't put that kind of effort into getting to know how their vehicle behaves, but that doesn't change the fact that the issues are there (and are likely correctable)