16' LC jerky transmission.. (1 Viewer)

[pepperdust]

hi guys,

seeing if anyone knows some common issues or tell tech what to look at. have a low mile ( 18k ) 16' LC with interment jerky shifting from 1-2-3rd gear. seems I can get it to do it more when say rolling through a stop and then hit gas, or if I'm rolling in traffic and it goes from 1-2nd gear without hitting gas and it upshifts..

I have no clue, as the techs can't seem to replicate it, so thus they will not look or work on it.

I did read the 16' can have the transmission software "flashed" when the 18' came out? yet I don't think this would fix it, as seems to be a bigger problem at play

thanks guys

 

[jwmNC]

You need the transmission software update. I had to really press my dealer to find this TSB, turns out they finally found it by going to the second page of bulletins in their computer system about the early 2016 model 200s:

T-SB-0209-17 (dated April 11, 2017) applies to 2016 LC's with VIN's before JTMCY7AJ#G4048393.

 

[CharlieS]

^this. I had to fight my dealer to get them to do the tsb, but it fixed the issue.

 

[Sandroad]

You need the transmission software update. I had to really press my dealer to find this TSB, turns out they finally found it by going to the second page of bulletins in their computer system about the early 2016 model 200s:

T-SB-0209-17 (dated April 11, 2017) applies to 2016 LC's with VIN's before JTMCY7AJ#G4048393.

Although it’s the same TSB number, there is a later update (Rev 2) from September 19, 2018 that now covers all 2016 and 2017 model year transmissions.

It will solve pretty much all the OPs issues, since that’s specifically what the new firmware does.

 

[pepperdust]

SHAKA boys, thank you, much appreciated!

if you visit Maui beers are on me

 

[LWA55DAL]

FWIW - I had a VERY early ‘16 and the transmission shifts were horrible in stop and go traffic. I had the software update done at least 3 times at the dealer. Each and every time they could not “duplicate” the issue, but it was obvious if you spent 10 mins behind the wheel. I had them do V1 and V2 of the TSB updates and the 2nd one helped, but it never shifted close to the ‘11 so I sold it and got a ‘20. The shift patterns in the ‘20 are much better, but not good IMO. There are a ton of threads on the bad shifts on the LC and LX from ‘16/‘17.

It will shift much better if you put it in “ECT power”, but you should not have to do that.

 

[AnyMal]

@Sandroad
Didn’t know there was a REV2 of the TSB? Do you know what VINs it addressed? I dont have jerky-ness, but just sloppy as hell shifting sometimes.

Generally I don’t trust the trans maps and drive in S7 pretty much 90% of the time. Transmission shift map is just not good, dont know if any update will help or not in my case.

 

[John Guedry]

Same had the tsb done on my 16 years ago, fixed my issue.

 

[druyang]

Looks like the lexus service bulletin is: L-SB-0118-17

Anyone have luck bringing a LC200 to Lexus for this TSB? The toyota dealerships around me are extremely hit or miss (depending on the tech), but the lexus one is solid.

 

[Mrtwooooo]

I have a 2016 LX and I'm trying to figure out if I need to pursue trying to get the reflash done.

My biggest issues isn't so much the semi-rough shifting but its the constant shifting when I'm at ~65mph. I can be at a constant throttle and start going up a slight incline. The car will slow down and I can't tell if its the torque converter unlocking or if its downshifting from 8th to 7th. I'll watch the RPMs when its doing this shifting and its like it shifts and then shifts back to where it was. Almost like it thought about downshifting, downshifted and then changed its mind. It makes the LX hard to drive smoothly. Is there at least a way to reset the TCU so it can relearn things?
Using the cruise control is even worse. Drive up even a little hill and its downshifting multiple gears. The cruise control tuning is terrible but I feel like that is a known thing.

The only thing I have to compare this to is my truck I use for work, a 2020 silverado 2wd with the 5.3 and the 6 speed. I can drive the same road at the same speed in my work truck and it will never shift, even with the cruise control set. RPMs are both pretty similar between the work truck and the LX at the same speed. I realize this is comparing apples to oranges with an LX vs a truck but the constant little shifting my LX doing is getting annoying.

Is this just a fault of having more gears?

 

[AnyMal]

I have a 2016 LX and I'm trying to figure out if I need to pursue trying to get the reflash done.

My biggest issues isn't so much the semi-rough shifting but its the constant shifting when I'm at ~65mph. I can be at a constant throttle and start going up a slight incline. The car will slow down and I can't tell if its the torque converter unlocking or if its downshifting from 8th to 7th. I'll watch the RPMs when its doing this shifting and its like it shifts and then shifts back to where it was. Almost like it thought about downshifting, downshifted and then changed its mind. It makes the LX hard to drive smoothly. Is there at least a way to reset the TCU so it can relearn things?
Using the cruise control is even worse. Drive up even a little hill and its downshifting multiple gears. The cruise control tuning is terrible but I feel like that is a known thing.

The only thing I have to compare this to is my truck I use for work, a 2020 silverado 2wd with the 5.3 and the 6 speed. I can drive the same road at the same speed in my work truck and it will never shift, even with the cruise control set. RPMs are both pretty similar between the work truck and the LX at the same speed. I realize this is comparing apples to oranges with an LX vs a truck but the constant little shifting my LX doing is getting annoying.

Is this just a fault of having more gears?

Lot of folks gone be mad but its just a dog bro.
Its both the shift map and throttle position map. Both trash.

 

[ljkup]

Looking to have this done also on my LX. Any idea if independent mechanics are able to do the flash?

 

[LWA55DAL]

I am pretty sure you need to be at the dealer and they will need to use TechStream to do it. That said I think either a Toyota or Lexus dealer can do it on either brand as TechStream will identify the vehicle when it is plugged in.

 

[thachnhen123]

I have a 2016 LX and I'm trying to figure out if I need to pursue trying to get the reflash done.

My biggest issues isn't so much the semi-rough shifting but its the constant shifting when I'm at ~65mph. I can be at a constant throttle and start going up a slight incline. The car will slow down and I can't tell if its the torque converter unlocking or if its downshifting from 8th to 7th. I'll watch the RPMs when its doing this shifting and its like it shifts and then shifts back to where it was. Almost like it thought about downshifting, downshifted and then changed its mind. It makes the LX hard to drive smoothly. Is there at least a way to reset the TCU so it can relearn things?
Using the cruise control is even worse. Drive up even a little hill and its downshifting multiple gears. The cruise control tuning is terrible but I feel like that is a known thing.

The only thing I have to compare this to is my truck I use for work, a 2020 silverado 2wd with the 5.3 and the 6 speed. I can drive the same road at the same speed in my work truck and it will never shift, even with the cruise control set. RPMs are both pretty similar between the work truck and the LX at the same speed. I realize this is comparing apples to oranges with an LX vs a truck but the constant little shifting my LX doing is getting annoying.

Is this just a fault of having more gears?

my lc300 just bought, 9,000km and same problem. very annoyed.