dansforest

Software mapping as far as when it will switch from gear to gear?

GSFRX350

Yes - the mapping was obviously made to improve fuel consumption figures, the tranny changes up too soon allowing the engine to keep the revs low and fuel consumption low. That way they can market the car with a better headline figure.

The TSB apparently changes the mapping to hold the gears longer. The original mapping works okay if you drive very gently and if there's not many hills around. Where I live in a relatively quiet country town that's predominately flat I can potter around, small throttle openings and the car is smooth as silk. When I go to the city the going is faster and the car shows it's hesitation, that's when I switch to Sports mode, she holds the gears longer and the hesitation is far better.

dansforest

That is what I thought you were stating. Just wasnt sure. So here is the question, should i not buy the car due to this frustration and look elsewhere?

gnguyen

There is also an inherent issue with the way the exhaust is design. It causes excessive vibration and droning. To me that is the bigger issue. If you read the thread and not scared, then go ahead and get one. Lexus never addressed this issue. The TSB worked for some people and did not work for others.

dansforest

The droning apparently is fixed for some by the tsb, others i read said they had to have the exhaust adjusted, physically. The dealer did it. I guess it is finding a dealership that knows what they are doing, or a car that has been through all this already, test drive it, and see if it is doing these things. Now i know what to look for, and that is gold. Thanks to these forums.

GSFRX350

No car's perfect, I feel the car is great in so many areas and smooth most of the time that I forget about it's minor (to me) issues.

gnguyen

Excessive vibrations, noise, and transmission hesitation are not minor issues. To each his own.

GSFRX350

Like I said to me they are minor, the vibration is only noticeable through the footrest when labouring and is very mild on my car. Noise, I thought it's an extremely quiet car, particularly since removing the F Sport resonator and the hesitation well, it's there sometimes under certain conditions but then I change to Sport mode and the hesitation is reduced or eliminated.

geefish

My 2018 RX350 has been a transmission nightmare. The new 8 speed transmission downshifts very hard coming down from 60mph to the 35-30 range. Very herky jerky. Had a software update which did nothing to improve the problem. Anyone else having same issue? if so was it resolved. It is a known issue with a possible pending class action law suit.

bitkahuna

iTrader: (20)

wow sorry to hear. moving this to the rx forum.

mikemu30

I feel an occasional "less than smooth" downshift on hard braking but far from a nightmare. Also the 8 speed isnt so new anymore.

dibl

My 2018 RX F-Sport has 21,000 miles on it and I have never felt such a thing -- it sounds like an issue with your unit.

rxtimes2

Did you get the new TSB (L-SB-0032-19) done, or the earlier one? The new TSB made a very positive change to the shifting of both of my RX’s.

Googs

Which is the latest TSB? I had one from earlier this year spring time and I dont think it made a change

rxtimes2

Check your paperwork. The latest is TSB L-SB-0032-19.