I have an 04 RX330 with 35,000 miles. It has had the infamous transmission problem (downshift lag, clunk, gear hunting) since new, which I've tolerated until now.

Last week I noticed that Lexus revised TSB TC005-03 on 2/9/2006, so I decided to go for it. Local Lexus dealer tried to talk me out of doing the TSC saying that it didn't help.

Well, at my insistance they did it anyway. (No charge invoice says that TSB TC00503 was done.) There has been no change whatsoever in my transmission's behavior. So, now I'm not only disappointed, but I'm wondering if the TSB was even done.

Suggestions, anyone? How can I tell if TC00503 was actually done on my car?

Thanks,
Ronaldo

 

I'm going to guess that it was done. My story goes like this. Everyone keept complaining about the transmission but I rarely had it act up on me while I drove it (Mine is a 2004 RX330 built in March 2003). My wife on the other hand did complain about it and said she noticed the funky shifting and delayed tranny shifts often while she drove it. I chalked it up to driving style and that my style of driving just happened to work better with this transmission, so I elected not to get the tranny update. Two months ago my car was approaching 50K miles which is the end of the warranty, so I decided to get everything done since we will be selling the car later this year. Long story short, I had them do the tranny TSIB update, and now my tranny acts funny even when I drive it. For my wife it is the same, but it is worse for me. I wish I never did the update at all.

So, my guess is that they did do the update on your car but it just doesn't help at all. In my case it made it worse for me.

 

I had the first version of that fix done (in early 2004, I think). It resolved the jerky shifting between 20-30 mph, but it never fixed the hesitation when stomping on the gas.

If they've done that TSIB, there MUST be a sticker in the engine compartment on the hood like the attached image. It must be there because the Transmission ECU is part of the emissions warranty.

 

If they did the upgrade you would notice a HUGE difference in the transmission.

It doesnt drive as well as a 2005, but the improvements are incredible. It's a big step in the right direction. The 1-2 second delay when merging into traffic is almost gone, as is the punched take off after coasting.

I highly recommend having this patch installed to your ECU.

 

Thanks for your responses. There is no sticker or decal inside the hood or anywhere in the engine compartment indicating that TC00503 was done. Is the decal really a requirement? Should I ask the dealer about it?

And, as I mentioned earlier, there is absolutely no difference in this car's drivability. It still pauses and hunts for the right gear when I try to accelerate from around 20 to 30 MPH. My previous Lexus did not have this problem, and one would not expect Lexus to let this defect go unresolved.

Incidentally, it appears that Lexus updated TC00503 in February 2006, and that one was supposedly done on my RX330.

 

I have all the TSIB and it still lags. I just got them to give me the 100,000 mile warranty for free. PS mines a 04 330

 

wow, a lot of mixed reviews. i had the TSIB implemented a few years ago in which they also replaced the transmission cooler lines and that helped a lot. i never had the hesitation that people talk about (but then again in my area by the time you merge on the freeway i'm already at 70mph). but, i did have the herky jerky gear hunting, especially in mild traffic where you are going between 20-30mph. that was annoying as hell, and what ultimately made me request the TSIB.

people thought that the ECU was learning your driving behavior, and since i drove very conservatively when i first got the car, i figured maybe that was partially why the thing was gear hunting. i don't know if that's true, but in any case, once i got the TSIB, i made sure to drive normally, not conservatively, and it's been driving great for 2 years. no hesitation or jerkiness and very smooth...