3rd Gen 2TR 2WD vibration while accelerating

Good afternoon all,

This is my first post on this forum and was hoping someone might have some answers for the issues I see with my truck.

I recently bought a used 2016 with 30k miles and have been experiencing a vibration while accelerating most noticeably around 1250RPM in all gears. This vibration does not occur in neutral, only under load. This truck is a 2WD, automatic transmission, and 2.7L 4Cylinder.

Another odd thing I see is that my truck shifts into a higher gear dropping the RPMs to around 1500-1600 then takes a few seconds before slowly dropping to 1250 before reving back up. This is while I am speeding up so it’s almost like a cvt delay after the transmission shifts.

I have read many of the forums about 3rd gen TSBs but most are applicable to the 3.5L 6Cylinder engines. If anyone has recommendations on things to check please let me know. I am a mechanically inclined 26 year old and have owned several Toyota vehicles in the past.

 

I have a manual transmission 3rd gen 2TR. Mine begins to object at any rpm below 2000 loaded. 1250 rpm is way to low. I don’t know if this is normal but maybe this is what you get when the EPA effectively chooses shift points.
Does it do this with the “ect” on?
I have not heard of others complain about this. Maybe call the dealer.

 

Update:
No it does not do it with the ECT power on, only because the truck does not drop below 1500 RPM. However, with the ECT on the truck is running at 2500 in almost every speed limit: 25, 35, and 45; which I feel is a little to high. The alternative option is running with the ECT off and the truck operates at 1200-1300 RPM at the same 25, 35, and 45 ranges... to low. It seems like maybe the transmission is programmed to maintain an RPM that is to low for the engine. Alow growl propagates from the rear end and the gas pedal/floor board vibrates almost like what you might hear and feel with a bad exhaust leak.

I will set up an appointment with my local dealer to make sure my complaint is on the books before I hit the 36,000 mile warranty end.

 

Vibration under load is normal at 1200 rpm with the 4 cylinder. Mine does the same thing, just need to keep the rpm up a little. I shift at 2500rpm for good gas mileage, 3000-3500 when trying to move a little quicker.

Don't be afraid to rev it, the 2tr can sing all day at 4500rpm and never complain.

 

Does anyone know why the truck changes gear and initially drops rpm but if I remain at a speed it is followed by a slower change in rpm down wards?

Ex: I will reach 35 mph and the truck will upshift, dropping RPMs to about 1500-1600. Then if I remain at 35 mph the truck will slowly bring the RPMs down to 1250.

I do a decent amount of back road driving so I can’t keep it above 1250 RPM if that is where the truck wants to be. I didn’t think tacomas had a cvt so is this a symptom of the variable valve timing or some other feature?

Thank you in advance.

 

Sounds like it is shifting into a higher gear. 5th and 6th are both OD. Try S5 and see if it stays at 1500 RPM.

 

Flex-lock or full lock of the torque converter...

Bad logic in flex lock-up can cause vibrations...

 

This isnt normal. My gfs 4cylinder is smooth as butter, it's my v6 that has it odd quirks

 

So I tried driving in the Triptronic mode of the transmission and the truck does not drop RPM's like it does in the automatic mode. I drove at all the same speeds that I get the vibration from in automatic. Is there anyway to view the transmissions current gear in automatic so I can verify if the vehicle is up-shifting or if there is something else going on?

EDIT: I just found this link to a discussion about flex-lock-up of the torque converter:
https://www.searchautoparts.com/motorage/powertrain-pro/toyota-trouble and this is exactly what my truck is doing. It only happens under next to no load conditions like cruising down a road at the speed limit just when the engine starts to load the transmission...

Has anyone else had these symptoms on a 3rd Gen 4cyl Tacoma?

 

I feel like I'm having these exact issues with my 2016 v6 TRD sport 2wd. have you figured out anything more? I was so worried about the transmission issues of it being low on fluid though I never had a problem with it till now at 72k.

 

I have a 2017 2.7 auto and have a similar RPM drop. Only does it after shifting into third gear during normal driving (after upshifting to 3rd, RPM will rise normally for a few seconds, then decrease by a few hundred RPM, then increase normally again until it upshifts to 4th). Has done this since I bought it new (now at 25k miles). No worsening of symptoms, no other transmission issues.

 

So after further analysis of shifting between Drive and Triptronic, I found that the RPMs cruising in what should be third or fourth gear match the triptronic RPMs at the same speed but in 6th gear.

Ex.: if I cruise at 40 MPH in drive my RPMs in 4th gear are about 1500-1600. They then drop to 1300/1400 and drop once more to 1100-1200. This only occurs under low load conditions like cruising on a flat road (most of my driving). If I cruise on the same road at the same speed in triptronic; the 1500-1600 RPM matches 4th gear, the 1300/1400 matches 5th gear, and the 1100-1200 matches 6th gear.

So the truck is up shifting from 3rd to 5th and from 4th to 6th. I have read that this could be caused by low transmission fluid or a badly programmed transmission. The engine dropping to those RPMs seems to be causing a flex lock-up of the torque converter when I initially apply a load. I will get this looked at this week and post the results.

 

I'm having the same vibration issue. All Toyota will say is that there is no service bulletin out. I also am having a slight shaking or shuttering at higher speeds when starting to go up an incline. Toyo tech went for a ride with me and stated that it is certainly there. Toyota Service Manager says nothing is wrong...end of subject. The feeling is almost like the way a vehicle acts when you are running our of gas. Let off the gas, and issue goes away. Step down and accelerate and the issue goes away. I have the 2.7L with auto trans.

 

My v6 does it. I had a Toyota tech (not a dealership tech) tell me it was normal. I asked the service manager if that meant that the truck was designed to shudder and shake, rather than down shift and he said yes. I am having another issue with tc lock up, referring to in TSB as a surge from 40-50mph that the computer updates didn't fix.... so I'm waiting on Toyota to respond to my repurchase letter.....