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Discussion Starter #1
when i throw it into first, second or sometimes third gear, a dull, deep thumping sound is heard....happens half the time...very disturbing....similar to when you try to select the gear and not have the clutch depressed all the way...

is this normal??? after i go into the gear, drop out, and immediately go back into it, it doesn't make the sound and feels so much smoother....

help me out guys...i'm bringing it back on monday....
 

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Its normal for our particular tranny. Use the search function and type in "Thud". It will kick out a shitload of info to confirm what I said.
 

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apparently all manual IS do this ..nothing to worry about.there has been much discussion here about it.just keep driving and enjoy your car.actually,you'll soon feel good about clunk you hear as as you engage 1st gear...don't worry about it,perfectly normal.
 

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Just turn up the stereo or rev higher and you won't notice a thing.
 

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ImpulseXvX said:
DonCorleone said:
in fact its so normal its explained in the owners manual, i would tell you what page but im holding my son.
put down your son at once! Go get that manual and find da page!
im gonna have to agree. if you could find the page, i would be very thankfull.
 

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i didnt even notice the "thud" until today when i was actually looking for it. for the past 3 weeks i have been driving with the radio on at normal volume and i never noticed it. i just thought about it today and turned off the radio and then i noticed. its not annoying at all, just a nice confirmation of the gearshift and the cars power. just turn on the radio and you'll never hear it again.
 

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Discussion Starter #9
whino said:
apparently all manual IS do this ..nothing to worry about.there has been much discussion here about it.just keep driving and enjoy your car.actually,you'll soon feel good about clunk you hear as as you engage 1st gear...don't worry about it,perfectly normal.
what about 2nd and 3rd??? is that normal too???

"when you go over a bump in the road, you'll hear a loud crackling noise"

that's normal too.....stupid toyota...
 

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Its normal. Go drive it and enjoy it. This car has some interesting engineering quirks but its all for the better of the car's life.
 

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Don't listen to these guys. I think there is something wrong. A car should make no noise at all, especially an uber luxury car like the IS300. Take it to the dealer. They'll probably try to BS you, but don't take any crap from them!


...The PL appears to be leaking...
 

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is it a thud, that makes the sound of a gear grind? if so then your synchonizer is prob. gone. take it back to the dealer and have them fix it. (they will prob replace the tranny). well they replaced it on a friends volkswagen for bad synchonizers.
 

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Discussion Starter #14
HIBBoyScott, yeah, i should've test drove this particular car before i bought it....now i have to fight with lexus to have them fix it...

n20, it's not a gear grind noise...it sounds like i'm forcing it in and "thump" there it is...not very pleasing to the ear..imo

DonCorleone, so what page is it?

all this talk about revving higher before shifting and blah blah blah...when you're at a light, you're not moving...

it's weird that when i'm at a light and i put it into first, then neutral, then first again, it doesn't make the sound the second time around....something is definitely wrong..
 

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This has been brought up sooooo many times now. THE THUMP IS COMPLETELY NORMAL! HIB is being stoobid.
 

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Yes, it's totally normal.

It is the result of slack in the drivetrain between the tranny and differential.

It is actually fairly common on most rear wheel drive manual transmission cars. Usually, it's not as loud as it is on the IS, but if you drive another rwd manny, you'll hear it if you look for it.

It is NOT a problem with the car. Lexus will NOT fix it for you. Every 5-speed IS I've ever driven (about 4 between my test drives and my own) has made that noise.

It has been discussed repeatedly.

The reason you don't hear it when you go into first, then neutral, then first again, is that when the synchros spool up, they eliminate the slack in the drivetrain through friction, slowly rocking the driveshaft into position.

However, when you simply "change" a gear while accelerating, it happens much faster, so the driveshaft "snaps" into action as it catches the teeth in the differential, making that thud noise.

Kinda like when you roll backwards a little, then forwards, you can hear your brake pads "click" fairly loud from them being moved slightly out of position by the friction being applied in the opposite direction.

DO NOT WORRY ABOUT IT. YOU ARE OVERREACTING, and wasting your time by bringing your car in. When you learn to shift a little smoother and adjust to this particular transmission, you will not even notice it anymore.

Hope this helps.

-C
 

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Gosha16 said:
ImpulseXvX said:
DonCorleone said:
in fact its so normal its explained in the owners manual, i would tell you what page but im holding my son.
put down your son at once! Go get that manual and find da page!
im gonna have to agree. if you could find the page, i would be very thankfull.
impulse was being sarcastic. sorry for some reason i cant find the page, i found it when i was looking for info on how to get the damn baby seat installed securely, but for some reason i cant find it again, maybe i mixed it up with the explaination about having difficulty shifting into reverse. like everyone said, its perfectly normal and you guys are overreacting. do a search on this topic and you will find it has been discussed many many many times over.
 

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HIBBoyScott said:
Don't listen to these guys. I think there is something wrong. A car should make no noise at all, especially an uber luxury car like the IS300. Take it to the dealer. They'll probably try to BS you, but don't take any crap from them!


...The PL appears to be leaking...
:lol: :lol: :lol:

some ppl cant detect sarcasm if their lives depended on it.
 

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Cleo said:
HIBBoyScott, yeah, i should've test drove this particular car before i bought it....now i have to fight with lexus to have them fix it...

n20, it's not a gear grind noise...it sounds like i'm forcing it in and "thump" there it is...not very pleasing to the ear..imo

DonCorleone, so what page is it?

all this talk about revving higher before shifting and blah blah blah...when you're at a light, you're not moving...

it's weird that when i'm at a light and i put it into first, then neutral, then first again, it doesn't make the sound the second time around....something is definitely wrong..
most likely, you are just overreacting, but theres always an outside chance you may have a legitimate problem, so heres how i propose you get a definate answer; find an is300.net member near you (or two), let him test drive your car and you can test drive his, if you have the same noise, then you're fine, if he can't produce the noise in your car but you can in his, you're not driving your car right. unless you find an idiotic member who doesn't know what the hell they are talking about then this should tell you what you need to do, either it be relax, learn to drive or take your car into the dealership. best way to do this would be to attend a meet in your area. btw you're sarcasm detector is broken.
 
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