2nd gear bucking for 6MT

I do the same thing with the pause near the end of the clutch. Seems to be the ticket for getting second to be completely smooth.

 

I am very familiar as to what it is and how it works (I did transmission work at one point automatics are full of them) I just don't see where it has made one bit of difference in the over all usefulness of the clutch. Zero difference as far as I can tell still I can shift just as fast with it no better or worse than any modern car I have driven. Judging from the size of the clutch accumulator it doesn't hold much fluid.

 

My wife still to this day says “I wish you’d learn to drive your truck” when it happens

 

As I said, some folks don't feel it. That is nothing to sweat.

For me, it felt different than other MTs up to the point that I hacked it out.


It doesn't hold any fluid. It is a restriction on the flow back up the line. The size of the disk is used to create negative pressure and compress the square seal to slow the flow. Simple but still a science project design for the worse, IMO.

 

Sorry for the thread ressurect, but I am experiencing similar behavior in my '22 trd offroad 6spd. It seems to have gotten significantly more noticeable over the past 1500 or so miles (at ~5400 currently).

I typically shift from 1st to 2nd between 3k and 3250rpm. Shifting lower than this makes it more noticeable, shifting as high as 4500rpm it feels "very similar" to shifting at 3k, by the seat dyno.

It definitely has a dead/flat spot in acceleration, very noticeable up steep hills in 1st at around 2200rpm, with the same deadspot seeming to be that much harder to accelerate through in 2nd and sometimes even 3rd gear.

I feel a definite "pulsing," almost a quick back and forth sloshimg sensation as the engine winds up from 2k to about 2500rpm.

When it first presented, it almost felt like a failed u-joint. Around 2300 miles I had a break in the weather and put the truck up on jackstands. I checked the driveline out. No signs of missing driveshaft balancong weights, no slop in the u-joints or carrier besring, all hardware still 1-Present and 2-Tight. I pushed the transmission ajd transfer case around by hand, no movement that I would consider "excessive" to explain the rebounding feeling. Engine is sitting nice and square in the engine bay, so I don't think its a failed engine mount either.

I did my 2nd oil change this past weekend, at just over 5k miles, and again checked all the driveline hardware and u-joints/carrier for signs of wear or damage.

I see some other threads with some tsb's for up through '17 and '19 model year manual tacomas related to 2md gear surging, but I don't see anything on nhtsa for '21/'22 models. Would these have already been "applied" when the ECU was originally setup, or should I contact my dealer and reference these tsb's, even though they are for several model years past?

I don't want to tune this vehicle yet. I'd prefer to stay close to stock for at least the first year or so to see if any issues present themselves. I will however be doing the damper delete for the clutch in the spring, and may try a short shifter to see if that reduces some of the slop when shifting. The accumulator kills the pedal feel, and about 70% of my shifts, no matter how I try to juggle and adjust clutch:throttle ratio and timing end up with a noticeable bumping sensation.

Edit- just wanted to add, this isn't my first manual vehicle. I learned to drive at 12, in my dads '93 runner [3.0/5spd], my first vehicle was a manual isuzu rodeo, then a 5spd pontiac vibe. I manual swapped my '99 3rd gen 4runner in 2019, as I had a complete '98 donor vehicle. I concurrently had a 6spd '08 mini, and replaced it with a 5spd civic. Point being, I've never had a "learning curve" like the one in this tacoma. Im hoping the accumulator delete helps tremendously.

 

i have owned and driven many vehicles with MT over the years and my '22 tacoma was/is the most difficult. i would not want to teach someone to drive in my truck.

i am happy to say though after nearly a year and 15K miles, we are getting a long better. it took a lot to get used to. mine is stock, i did not delete the accumulator.

 

The clutch in this guy is a bit touchy. Just practice some more and you'll get there.

It's not as smooth as my VW Golf or my '86 Land Cruiser, but it gets the job done. I think it'd be a lot better if the throttle did what your foot is telling it to do as if it were connected via cable.

 

First of all, welcome to TW! I have the same issue with my '21 which is one of the [few] shortcomings of this engine/trans combination.

As others mentioned, you have to rev it up in first gear, especially when cold, which of course, we all hate to do. Another option is to punch the accelerator hard in first gear and shift quickly into 2nd, even if your speed is below that of the ideal shift point. A third option is the running start, for example hanging back from the stop light when you have to turn uphill immediately at the intersection, getting the speed up in first, and shifting before the hill.

 

My wife is 5 foot 100 pounds she has no issue driving my truck (Toyota pickup#3)other than she thinks it's big. Bone stock, 160K miles same clutch even towing an 18' camper same accumulator it came with. Now I have only been driving for 60+ years and spent 38 years repairing vehicles so that may have some thing to do with it.

 

My solution (more of a bandaid than a fix) is as soon as I feel a buck or pulse I take my foot off the accelerator for a split second and then get back on. It always accelerates smoothly after that. I don't know why it works, but it does. It must trick the programming or give it an extra half a second to think about what it should be doing. I think it's a software/tune issue and not a clutch accumulator thing.

 

Maybe I’m missing something, but isn’t this just about “lugging” or “bogging down” because the rpms are too low? The torque curve of this engine doesn’t help.

 

Doing the ADM disk mod coming up, but this bucking has been quite normal in many manual cars I've driven over the years.

 

This also is something I've found to help. But it's annoying. I guess I didnt put it there, but I was wondering if anyone knew if the TSB's for the previous model years solved this/were applicable to a '22 model.

 

I've never had a vehicle that "lugs" like this, when under throttle input, even agressive throttle input, in 2nd gear on flat roads.

I feel the "dip" in power (torque, I guess) above 3600rpm more than this, but without the same "hop-hop-hop" sensation in the seat.

 

Bottom line it's not the transmission.

 

I found that some gasoline does it for my truck.

 

I don't think so. Toyota appears to have a very conservative electric throttle tuned in and it won't open the throttle fully at low rpm.

This truck acts very similar to old two strokes when lean. In watching an obd reader I see what I believe to be the same thing, as you roll into the throttle the computer starts to richen up the mixture and then quite suddenly locks out the fuel trim.

Now tonered is going to come in and yell at me again to go get a tune...

 

Well aware. ~~Generally engine issues are related to the engine.~~

While it certainly could be the loose nut in the captains chair, I'd say my previous experiences with manual transmissions across a range of vehicles minimizes the chance of it being all on the driver.

 

had my 23 for a month now its extremely hard to shift smooth. huge difference getting out of my 6mt corolla that you could lug under 1000rpm and still be butter smooth. definitely bucks and throttle surges if rpms arent "ideal". kdmax tune and accumulator delete coming up.