SkipABeat

Driving on the highway this morning, I felt a little jerkiness when I sped up or down as the traffic flow dictates. This is very unusual and the first time I have experienced it on my 23,000 miles 2004 LS430.

Doing a steady 60mph, I realized that my tach reading was around 4000 RPMs. The car is so quiet that I had a hard time telling it was revving that high. Normally I am at around 2000 rpm at 60-70 mph.

My ECT is in the normal driving position (not in SNOW nor POWER).

After 15 minutes on the highway, I pulled over and turned off the motor completely for a minute and the problem was gone.

Can anyone shed light on this problem? Thanks )

The transmission is sealed so I cannot check the fluid level.

AlexusAnja

You have a 2004 or a 2005? There was a recall on early production 2004 transmissions. Maybe check to see if your vehicle was under the recall. Other than that, it's not usual for what happened.

SkipABeat

I have a 2004 (I edited my 2005 typo).

AlexusAnja, why was the early transmission recalled? When I bought my vehicle in July 2008, Lexus USA issued a recall clearance letter for my car before I can import the car to Canada. But I think I have to double check myself. Where do I find this info?

Thanks.

aypues

Did you have the TSB done for the shift pattern enhancement? That helped my 04 trans.

socal3

iTrader: (2)

What was the outcome of your problem?

AlexusAnja

I would just call Lexus Corporate and find out directly. Give them your VIN and they'll tell you if it's under the VIN range and if it was done or not. The recall was for I believe excessive flash from the transmission internals, resulting in lockup or inabiliity to shift in and out of park correctly. I THINK... not positive. Anyway, it required the replacement of the transmission.

Someone mentioned the shift pattern change, that would not resolve what you have. You're having a "physical" problem, not just slow shifting at low speed.

Anyway, call corporate, it's your best bet. Good luck.

Slvr surfr

iTrader: (1)

I experienced the exact same problem in my car a couple of weeks ago. Only diff is my car is a 05. Started before and while i was on the freeway. Once i exited the freeway after about 4mins, i came to a stoplight then drove off but everything was fine and it never happened again til this day. Strange to say the least.

SkipABeat

I checked my VIN, and it wan not recalled for transmission replacement. Since the day it happened, I have been trying to figure out if I had accidentally bumped the lever into the "S" position. That would have required a very firm bump to move it to the left. And assuming I did that, I would still be in drive range "5" by default. Would that translate to 4k rpm at 60-70mph? I do not think so.

I called a reputable independent Lexus shop and explained my experience to the lead tach. He recommended a tranny flush and refill. My car has only 23,000 miles, and the tranny fluid is good for 100k. So should I do it?

SkipABeat

My problem happened when my motor was not fully warmed up. I must have travelled no more than 4 miles before I entered the highway. How long were you driving when it happened?

Slvr surfr

iTrader: (1)

Same situation here. Car warmed for no longer than a min before i started to move. When i left my complex, it was all down hill for about a half a mile. I guess short warming period + a trip down hill sent the wrong message to the computer im figuring. Right after i got off the downgrade i hit a two lights and then the highway. Havent seen the problem since and really dont want to see it. All good so far.

Vpanin

dont let them mess with the tranny fluid at that mileage

AlexusAnja

Multiple things I want bring up:

1. I live only 2 lights from major freeway and I've never had high revving entering and doing 65 mph. I know that Lexus did this with early engine/trans combinations (i.e. my '99 RX300) where they would retard the transmission from shifting to highest gear to speed up the warming up. I do not think this would have been engine warm up related.

2. If you accidentally did hit the gear selector into "S", it would have stayed in "S" and you would have felt it again... so I would say it was NOT in "S" or you would have shifted out from "S" and noticed. Unless you just shifted out without noticing. IF HOWEVER you did shift at highway speed to "S" that would have bumped it down to 5th gear and the RPM probably would have gone up and stayed. I have not tried it, but I've read the LS430 "S" mode does have the ability to hold the RPM at redline if the owner wants to do that. Most "S" mode trans will always shift out of high rev to avoid damage. THIS MIGHT be your culprit.

3. Changing the fluid seems just like a "let's just change it cause it's easier to do" thing by the dealer. The fluid is WS and supposedly NEVER has to be changed... so at 28K, unless your transmission really is faulty, the fluid should be "fresh."

4. I would say just be careful of it and see if it occurs again and if it does... observe for any patterns of when it might have happened.

Slvr surfr

iTrader: (1)

Personally i think it was just a glitch. But im keeping my eye on it from now on and monitoring the shift patterns to see if there's any change in them. My car has +92k on it so its probably time to maybe do a flush and fill on the tranny. Not saying that is the cause or solution but i'll feel more comfortable with fresh fluid in plus i will know the state of the old fluid also.