NyCrAzY

I noticed when I accelerate, the car makes an uncomfortable jerk when switching gears as I speed up. This happens sometimes though, mostly when the car is cold.

Is that normal orrr?

99rx

iTrader: (6)

Mine does it when it's cold sometimes. Once warmed up, all is flowing smoothly.

hypervish

When it's cold, for the first 2-3 minutes, the 1 to 2nd shift you can feel. But, after it's warmed up it's silky smooth just how a Lexus should be.

If I give it to my dad to drive, who loves to speed, but get's up to speed slowly (ie. no redline, no over revving). When I get it back, and I drive it like I normally do (i.e. redline, lot's of unnecessary over revving), you can feel the shifts, till it realizes I'm back in the driver seat. After a few shifts, it's back to being silky smooth.

So, try resetting the ECU? Also, what type of transmission fluid do you have? Once, I switched over to Castrol Multi- Vehicle ATF which is a synthetic-blend, I feel that it shifts a bit smoother when cold. Probably because it's a synthetic-blend which gives it an advantage in the cold.

One more thing to mention, generally speaking, the more you feel the shifts the less wear on the transmission. Because, the car won't be trying to smoothen the shifts by working the clutch bands, etc.

hypervish

I probably should have asked this before. But, do you mean when you shift from park to reverse, park to drive. OR do you mean while actually driving?

For the first part, when my RX is cold and still under the "C" line on the dash, I can feel a jerk when shifting from park to drive, or reverse. But, this only happens when the pointer is under "C". After it reaches "C", you can barely feel it. Once, it's up even further above "C", you can't feel it at all.

lserlohn

Does your Trans jerks when you shift from D to R, P to R, when engine is warm?

I sometimes feels a jerk when shift from D to R, when engine is warm. When engine is cold, I can't feel it.


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NyCrAzY

After doing many tests, I've found out it only does it when the car temp needle is below the "C" ... guess I should have more patience when warming up the baby in 30the degree weather :P

AJAA

Mine is doing it quite often and I'll have to check, but I'm pretty sure it doesn't happen only when cold. Had the tranny fluid "exchanged" with Toyota Type 4 fluid, at 90K miles (even though these models are supposed to have lifetime tranny fluid); however, I understand that there are well-known computer problems with automatic shifting in my 2004 model.

DrDan

I have a similar experience when my 2003 RX300 is cold. Within the first mile, at about 25-30 mph I get a strange shifting-like experience. It feels like I forgot about the parking brake being on and I drove off. Then when I discovered the drag, I released the brake and the car hesitated, just a tiny bit, like a missed shift. But, the brake was not on and as far as I can tell, it did not shift and the speed does not change. It only happens one time when the engine is cold. It shifts perfectly normal ever after. I recently had my timing belt changed and a full transmission flush at 88,000 miles

It is that unexpected, but almost predictable “between shift” hesitation. If it were a standard transmission, it could be described as driving along, quickly depressing the clutch and releasing it without changing gears.

I am not too worried about it, but my experience might add to the discussion.

Dr. Dan