Transmission Issue - Dealer Claims Nothing Can Be Done

[whereisthelye]

Hey everyone,

First off, other than this recent issue, I love everything about my GX550. No problems or complaints, outside of maybe wanting a larger stock gas tank.

Currently at 11k miles, at 9k my GX started lurching/clunking as I came to a slow stop between 1-2mph. This happens regardless of whether my foot is on the brake or not. I took it in to my dealership to diagnose, and they are claiming there isn’t an issue, that’s just a “quirk of the GX driveshaft”. I’ve seen on this forum similar issues that were solved by resetting the memory on transmission, but they said they can’t do that without a software update.

It feels like it’s getting worse, not better. Even if it’s not dangerous, it’s like the hiccups: happens so often I’m constantly aware of or expecting it and it’s extremely annoying. They basically said it’s fine and if it gets worse, take it in, but I’m frustrated that I spent 80,000 on a new car and I have to deal with something that so adversely affects the driving experience.

Any advice on what I should do? I have an appointment with a trusted mechanic for a second diagnosis, but it feels like they told me I just need to grin and bear it. Thanks so much!!

 

[GX550_OT]

Hello, I experienced the same issue and response from Lexus. From what I experienced, they will not do anything unless you ‘request’ the TCM Memory reset. The reset is not technically a fix, therefore they won’t recommend or offer. It’s just a temporary fix. Hopefully something comes out soon to remediate.

 

[FJMainiac]

I am one of those owners with similar downshift clunk that was fixed with a memory reset. This was about 3000 miles ago, and everything is still completely smooth. In a discussion with a friend that works at a Lexus dealership, he mentioned that sometimes first year models will get a software update to remedy things like this so maybe a remedy will be forthcoming in the future. Not sure if this "hack" will work or not but something you can try on your own: unhook the battery for a few minutes and then reconnect.

 

[RPMSTL]

I don't have the downshift clunk but definitely have the stammering first shift of the day from 1>2.

I think these issues can be remedied with software changes.

Holding 1st gear a little longer on a cold transmission and not shifting into low gears until a dead stop seems like a
possible fix.

 

[Bluegill]

Print this out, go to your local dealer, slap the service manager upside the head, and then show this to them.

https://www.lexusgxforum.com/attachments/gx550-reset-tcm-memory-jpg.7522/

 

[incognito.gx]

Transmission reset helps but ultimately need a software update

 

[whereisthelye]

Thank you all, I appreciate your help. I’m going to call them again and be a pain until someone agrees to do a TCM Reset. Fingers crossed for the update soon…

 

[ValhallaBrook]

I don't have the downshift clunk but definitely have the stammering first shift of the day from 1>2.

I think these issues can be remedied with software changes.

Holding 1st gear a little longer on a cold transmission and not shifting into low gears until a dead stop seems like a
possible fix.

Glad to hear it’s not just mine! The trucks at 9k miles and it’s only getting more pronounced.

 

[rnr]

Have about 8k miles now, and I have noticed both of these issues. Definitely have intermittent what I would call hard downshifts, so I’ll try the tranny reset. Also, sluggish shifts first thing. I really try to let it warm up, and also drive it in sport mode and both seem to help. As one person said, just get on it a little more and that seems to help also. I’ve noticed that helps with most driving characteristics on the GX. Anyone solved the issue with the A/C button always defaulting to “off”?

 

[mahlogic]

Same issue, OT with about 12k miles - getting really bad and consistent. Same response from the dealer. Has anyone opened a case with Lexus Consumer hot line? If so, let's share ticket numbers and push them for a solve fast. Agree that a $75k+ luxe car should not do this!!!!

 

[XYR03]

Mine does the same thing. Hard downshifts at low speeds. Can the reset be done by owner?

 

[incognito.gx]

Mine does the same thing. Hard downshifts at low speeds. Can the reset be done by owner?

No

 

[Laxal50]

WOW! I'm so glad I found this thread. I am having similar issues and convinced myself that I was imagining it.

When rolling to a stop I notice a shutter when braking below 5 mph. It's not a pronounced shutter but very subtle. I chalked it up to downshifting, but at that speed it didn't make sense. THEN I wondered if it had any thing to do with the brake squeal recall that was fixed a few months back. They did the new pads etc.

I'm following this thread to see if anything develops. Not sure who to report this concern to - please advise!

 

[ajt322000]

Which trim guys?

 

[Bluegill]

Take it back to the dealer, have them reset the transmission memory. Reset TCM.

https://www.lexusgxforum.com/attachments/gx550-reset-tcm-memory-jpg.7522/

 

[rnr]

Overtrail + for me.

 

[Laxal50]

OT+

 

[Bluegill]

OT

 

[whereisthelye]

Print this out, go to your local dealer, slap the service manager upside the head, and then show this to them.

https://www.lexusgxforum.com/attachments/gx550-reset-tcm-memory-jpg.7522/

I tried bringing it back, even gave them a copy of this file. They are claiming they are not able to do the TCM Reset without a code popping up or a software update. This is the BS video they gave me…

Media Microsite

x1con.xtime.com

 

[whereisthelye]

I tried bringing it back, even gave them a copy of this file. They are claiming they are not able to do the TCM Reset without a code popping up or a software update. This is the BS video they gave me…

Media Microsite

x1con.xtime.com

Please forgive the dirtiness, roads are salted to hell and back and I couldn’t give her a bath before I took her in