2018 Tacoma Limited 4x4 Transmission

Ok, I know this is a topic that has been beaten to death but I’m not sure what else to do. I love everything about my Tacoma except the drivetrain. I’ve had an OTT tune done to my truck but I guess it didn’t take and then I had the MCB Auto Elite tune done which made the truck run much better for about a month. Now it’s back to gear hunting, there’s a slight shudder from the bed of the truck too. I’m afraid it’s a possible torque converter issue—I’m hoping not though. The RPM needle also ticks/flickers up and down when it’s gear hunting. Anyone else experienced this? It’s driving me crazy and causing me to miss my first gen Tundra.

 

If the torque converter is shuddering you should start with a transmission service.
How many miles on it and has it ever been done?

 

I just had the fluid replaced about 5k miles ago by Toyota. It’s got 89k miles.

 

7k neutral drops fix every transmission problem.

 

Verify the fluid level is correct first.

 

Will do! The strange thing is when I’m in “S” mode shifting myself, the issue goes away. There’s still a slight shudder and I’m thinking that may just be a u-joint that either needs to be greased or is giving out.

 

I run mine in S mode all the time, the tranny is too eager to get into 6th gear. I usually don’t even use 6th until I get to 70+ mph, the 3.5 isn’t very smooth when it’s lugging at low rpm. You could almost think it’s misfiring or shuttering.
There have been a few TCC shudder issues on 3rd gen’s, but not a chronic thing.

 

Yeah, keeping it in 4th is so much smoother and I can actually merge on to an interstate lol. I’m going to have a reflash of the MCB tune too and see if it’ll stick. I wish I could upload the video of the RPM needle flickering/fluttering at 2k RPM.

 

You need to rule out the tune effect. I've interacted with members of that group to fix some shifting and tc management on their previous tune.
Refreshing won't help. You need data logging to see what they are doing with tc management at those conditions. Moving RPM needle most likely related to tc turning on and off at given speed/load/accelerator position etc.

 

Thanks! That’s good to know, I drove into work today and my truck was perfect. It’s strange how intermittent this issue is. I left it in “d” instead of “S” mode on my way in today. What’s the best way to find that data out?

 

The issue is typically related to driving conditions ( the road profile, engine rpms, the speed, the gear, torque converter state).
You need a obd2 app to capture those conditions and address them with the tuner.
Obd2 fusion phone based app is a simple and cheapest way to get the data.