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Maverick
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Just got my IS300 5speed Premium Edition three weeks ago. Luv it, except for the cramped footwells (they didn't consider us 6' guys, did they) and this following issue.

I get a "clunking/thumping" noise, coming from what sounds to be the rear of the car, in the differential area, when I shift.
It happens as such: I press in the clutch, then move the shift lever from 1st to second..then CLUNK/THUMP...then I release the clutch and am on my way.

This is most noticeable at low gears i.e from 1 to 2, or 2 to 3..and can't figure it out. The car is brand new, I make sure to depress the clutch level ALL the way down..yet still the issue.

Any guesses? :roll:
Thanks
Mik
Toronto, Canada
 

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It's normal.
Search for "THUMP" and you will find many topics discussing it.

Here's one useful reply:
RxVedub said:
BTW the thump is not just a tranny issue, more of a combination of chassis design and sincros in the trany. The sincrose grab the gears so fast and hard that it sends a shock wake thrue the drive shaft and the dif. The dif mounts absorb the shock, but the chassis design projects a "thump" noise when this occurs. There is no fix it on this problem only chassis redesign.

No bull sh*t, strait from my Lexus class at the western regional office.
 

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Yup...the noise is common to manual IS300s.

You'll find that if you shift smoothly, and hold the gear lever at the next gate allowing the synchro time to spin up and "suck" the gear into the gate, that this will reduce the thumping as compared to forcing a gear into the gate.
 

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annoying yet normal...there are actually two thumps associated with our car...the one you're hearing is from the transmission (due to the gear selection)...the other comes from the rear differential.

follow teCKis300's advice and ease your shifts into the gate...i do this all the time and the thumping is minimized...also double clutch when downshifting as you enter a corner
 

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Mikster said:
Just got my IS300 5speed Premium Edition three weeks ago. Luv it, except for the cramped footwells (they didn't consider us 6' guys, did they) and this following issue.

I get a "clunking/thumping" noise, coming from what sounds to be the rear of the car, in the differential area, when I shift.
It happens as such: I press in the clutch, then move the shift lever from 1st to second..then CLUNK/THUMP...then I release the clutch and am on my way.

This is most noticeable at low gears i.e from 1 to 2, or 2 to 3..and can't figure it out. The car is brand new, I make sure to depress the clutch level ALL the way down..yet still the issue.

Any guesses? :roll:
Thanks
Mik
Toronto, Canada
What constitutes a "Premium Edition"?...a "Premium" on the sticker?
 

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Mikster said:
Just got my IS300 5speed Premium Edition three weeks ago. Luv it, except for the cramped footwells (they didn't consider us 6' guys, did they) and this following issue.

I get a "clunking/thumping" noise, coming from what sounds to be the rear of the car, in the differential area, when I shift.
It happens as such: I press in the clutch, then move the shift lever from 1st to second..then CLUNK/THUMP...then I release the clutch and am on my way.

This is most noticeable at low gears i.e from 1 to 2, or 2 to 3..and can't figure it out. The car is brand new, I make sure to depress the clutch level ALL the way down..yet still the issue.

Any guesses? :roll:
Thanks
Mik
Toronto, Canada
premium edition? :lol:

-ringo
 

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Premium is an option package for Canadian IS300s. Pretty much means it's fully loaded.
 
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