Downshift into 1st Gear Clunk and then roll (NOT axle wrap)

This is different from axle wrap. The truck will downshift as I'm coming to a stop and the increase in rpm will slow the truck down as it goes from 4th-3rd and 3rd-2nd. Then, it'll shift into first, clunk, and lose the pull-back feeling that you get when you downshift (almost like the truck has slipped into neutral and rolls until I apply the brakes hard enough). I know this isn't axle wrap because I feel nothing at all when I throw the truck into neutral coming to a stop or move it into S mode and quickly shift up to 6th when coming to a stop. It's worse when I come to a quick stop as opposed to a slow rolling stop. Dealer says eventually the engineer will come to Columbia and look at it; in the mean time, it's driving me nuts. Dealership already manually checked the tranny fluid and reset the transmission software. I was in the back when they pulled the drain plug and everything, so I know they're telling me the truth. Any ideas? I have a 2017 TRD OR 4x4 with the tow package. About 2200 miles on it and it's been doing it since about 500 miles.

 

What speed are you at when you shift 2-1?

 

Nearly stopped; probably somewhere around 5 mph

 

Side note -

The stick doesn't work the way typical slap shift style shifters work.

When you say 'or move it into S mode AND QUICKLY SHIFT UP TO 6th' it shows what I'm getting at.

When you shift over to 'S Mode' a 4 appears and then for instance you slap it up twice to '6' , that isn't shifting the gear. The number you see is what gear the transmission is limited to. So the 4 means the transmission will shift between 1,2,3&4, while the 5 adds the 5th option, but doesn't mean you are in 5th gear when the 5 is showing.

 

Thanks for the info - this is my first automatic in 10 years.

 

Me too

I was hoping it was a tiptronic / slap stick but when you are at say 30 mph and shift from 4th to 5th to 6th it won't necessarily up shift

 

S2-S1 downshift permission speed is 25-31 mph.

 

is this just in standard D mode? because i have incredibly harsh/clunky shifting from 2-1 on my truck too. drives me crazy.

 

Yes. I don't drive in S mode very often because I don't like a "fake" version of a stick shift. I'm sure I'll get ripped on for that but if I'm gonna tell the truck when to shift, I want it to shift exactly when I tell it to... just my opinion.

My issue is partly the clunking and also partly the fact that I lose all pull-back feeling once it shifts into first. If I'm easing off the brake to keep the stop smooth due to the brake booster, I find myself needing to hit the brakes to ensure I don't go into the car in front of me.

 

Sorry; I was under the impression your problem was in S mode.

 

No I appreciate any insights. I just want to get this figured out. Outside of this problem, I love the truck... but driveability trumps looks, size, or anything else that is attractive about it.

 

Yep. If it makes ya feel any better this is happening verbatim on my '16 SR5 ACLB. Already brought my truck to the dealer at 2k and they couldn't solve it so they started a case with corporate but haven't heard anything.

EDIT: 4X4 V6 I should add

 

Happens on mine too, I've only got 200 miles, it's much more pronounced when the truck is cold, as it warms up the shifts from 2-1 seem to soften

 

Happened on my 16' AT, also more noticeable when it was cold. Before I got rid of the 16' I started using S mode and noticed a lot of the auto issues are less common on S mode.

But yeah it seemed like it was very reluctant to drop to 1st, the shifts down from 4th to 3rd to 2nd all happened at about the same rate of speed, then it would take longer to go into 1st and clunk. I don't recall it feeling like it fell into neutral. On one hand it was irritating, on another it seemed like the truck was programmed to trail brake and would decelerate better.

 

The flex lock bullshit is cancelled in S mode.
Flex lock is supposed to smooth out shifts. Supposed to...
From what it looks like, the new TSB will address this; at least that is my hope.

 

New TSB? Is there another one in the works or are you talking about the one that came out over the summer?

 

Sounds like a " SQUAWK " control issue
When you are in park and move the shifter to drive when the truck is cold , does the truck have a clunk on the initial application or is the application into drive very smooth ?
Have you tried rolling to a stop in neutral ?

 

I have a similar issue, although it's sporadic. My dealer "can't reproduce it", so I've learned to live with it. It's incredibly annoying when it happens and embarrassing if I have someone riding with me.

 

Im not quite sure this is a transmission thing. This happens on the manual transmission as well. I get engine braking until roughly 1500 RPM, and then there is a "release," small buck and the engine braking stops and, like you said, the acceleration rate feels as if I threw it into neutral (although im not in neutral of course and if I step on the gas I accelerate).

I asked the service guys when I was there for a different issue, he said it's an engine management thing and common these days with drive by wire, even though it's annoying.

 

https://www.tacomaworld.com/threads/bump-after-stop.456356/

https://www.tacomaworld.com/threads/transmission-thunk-and-grind.457979/

Ive got the same problem