iluvny

I've read in the forum about transmission shift problems between certain gears with these cars but don't know if my symptom applies. 2004, AWD with 35k miles, however mostly short stop and go driving.


When applying the brakes to come to a complete stop, there's kind of a abrupt downshift that I can even feel in the brake pedal. The car even has a last second little shake and a bit of a clunk..

Difficult to describe, so here's a short YouTube video as well. (you may have to turn up the vol to hear it)

Edit: definitely not the transmission. Pulling the ABS/VSC/TC fuse , the car brakes normally. Skid control affects turning in curves and TC affects acceleration. So, it's ABS related..

kiwi

first things first, check / change the trans fluid

iluvny

Naturally, the first thing I did was check the fluid level and color. Too cold here to change the fluid, so thought I'd post here to see if anyone else has experienced the same symptoms and found it more serious than a fluid change solution.

Rainbird

There are 12 Technical Service Bulletins on the 2004 RX330 in the database for the automatic transmission. Check it out:

http://www.revbase.com/BBBMotor/

kiwi

changing the trans fluid does not relate to temperature. Up here in canada, we can do it yer round, so by default, anywhere in the US can be done year round.

when do your records indicate it was done last?

if you do it yourself, it takes maybe an hour. and less than 100 bucks

iluvny

@Rainbird......thanks for the link, however, none of them seem to refer to my problem.

@kiwi.....I'm talking too cold for me. Would have to do outside and freeze my a** off. The fluid has never been changed (we bought the car new), again, only 35k miles, but lots of local driving.

kiwi

WOW, fluid dies with age too. its way over due, just on time.

you might want to consider letting the dealer do it. or another shop (just buy some OEM fluid). Most people notice a difference after a drain and fill

iluvny

Oh, I can do it all right, no problem. It would be great if that "cures" the problem.

kiwi

even if it doesnt, it NEEDS to be done, so dont feel like its wasted money if it doesnt cure your issue.

always start with the cheapest, maintenance based cures first.

also, i think there is a TSB about a software update. you are out of warranty, so you will have to pay the dealer to have it done, assuming you need it.

iluvny

Yes, I've read about that update in this forum and it seemed to help some and for others actually made things worse. However, none of the shifting symptoms mentioned in the TSB apply to my car.

I had planned on doing the fluid change before the op. The dealer claims they haven't seen any other cars (all models of Lexus) with the same problem which, of course, I find difficult to believe..

kiwi

the other option is for them to call technical support.

Dealer mechanics have access to a call centre or sorts for them to get assistance. perhaps the problem has come up elsewhere in the country.

nonetheless, change the fluid and report back

iluvny

Update: Ok, finally got round to changing the fluid (drain and fill) and no change in the symptom. Only a couple of miles test drive, going through all the gears. I'll take it on a longer run and see if the "fluid mix" changes anything.

RX330inFL

Is this vehicle FWD or AWD?

iluvny

Wow, I can't believe I didn't mention that. It's AWD

Edited the op to reflect this.

RX330inFL

Check your front transfer case, gear oil level and quality. Has it ever been touched? I understand this is a low mileage RX, however, it may be low and by now age would be a reason by itself for a change. Only holds 1QT of gear oil, and a Mobil 1 75W90 would suffice for the job.