my friend was following me one day and notice when i GAS it, my stock exhaust shake up and down. But when I'm just cruising it's fine...WHY? is something loose?

 

Not too sure if our cars have hangers or anything but see if theres a broken/loose hanger.

 

its normal, most bmw m3's i see on the road do that on a bumpy road.



its all good dont worry about it, your still in a Lexus

 

it happens to all lexus, as long as it does not shake too hard that really hit the body of the car, you are fine...

 

most exhaust systems these days (stock at least) are built to bounce up and down with body movement so they aren't damaged or hit the body..our IS's have 6 seperate rubber hangers, they are very safe..in any case just check that all the hangers are there and in-tact

 

Yup, what everyone said. my buddy with an E92 actually mentioned this to me a few weeks ago.

 

You can also use a big zip tie and wrap them around the hangers. This will minimize the effect like you're describing.

 

i used hose clamps to stop the bouncing...

 

You cant hear it right?

 

yep, i was on the way to the dealership as my friend followed me. he said my exhaust bounces a lot but everything was attached correctly to the flanges, so when i pulled into the service department, i had them check on a brand new IS sitting in the lot. All of them are like this

 

Normal. I used to use hose clamps on my TL. but that was because the exhaust was uneven.

I recommend this. You can only swap out four bushings on our cars. Two of them is bolted down.

Cusco Exhaust Bushings.



No more bouncing up and down.