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Discussion Starter #1
Hey guys,
got my new black IS300 four days ago. Was reading owner manual and it said not to take the car over 55mph for the break in period of 1000 miles.
Dealer told me to drive it as you would another car just keep the rpm's low...

I've been careful not to let the car go over 4500 rpm but have coasted at 75 mph on the highway...

any thoughts on proper break-in?
 

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Originally posted by sambusik:
Hey guys,
got my new black IS300 four days ago. Was reading owner manual and it said not to take the car over 55mph for the break in period of 1000 miles.
Dealer told me to drive it as you would another car just keep the rpm's low...

I've been careful not to let the car go over 4500 rpm but have coasted at 75 mph on the highway...

any thoughts on proper break-in?
my cl-s has a 600 mile break in and it says not to exceed 70.

from my porsche tech classes i can tell u that an engine needs to be gently broken in across a variety of rev ranges. just driving slow is not the best approach, nor is building revs quickly. build revs and speed slowly and steadily, and occassionally accelerate for no reason. same for moderate deceleration. just do it safely and not in the middle of traffic. i figure u lexus types need to be told that.

that's my useful post. u can go back to flaming me now bitches
 

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I have the same problem. I am up to 185miles on mine so far, but I can't see how I can get on the Freeway and still keep it under 55mph.

Basically I have decided to keep it under 4K RPMs at all times (no matter what) until 1K miles, and keep it under _70_MPh. I try to vary my speed as I drive going between 55 and 65 when on the freeway. I have hit 70MPh a couple of times and then slowed back down.

The manual (and what I have heard before) recommend not staying at one constant speed for very long. I think that having some sort of "continuous harmonic vibrations" can cause uneven wear on certain parts. So - DON'T USE THE CRUISE CONTROL during break in, and try to vary your speed as you drive.

I am hoping that the 55MPh guideline is just a generic suggestion that they offer, and that since the IS300 gearing keeps it under 4K RPMs (in 5th) even at 70MPh it may be OK to exceeed 55MPh a bit.
 

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TEG, harmonic vibration or natural frequency only occured at certain frequencies or normal modes. You don't have to worry about that since engine designers have done their homework (or I hope so) to keep the natural frequency either extremely low or extremely high, so you will never touch them. And I don't think you will ever want to see your engine hitting a natural frequency because it will just self destruct. Fun to see in a lab, but not in real life especially if you are the owner of the car.
 

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Discussion Starter #6
Hey Teg,
good point, I'm able to enjoy the car and maybe push it a little bit while keeping the rpm under 4K and speed right around 75mph.

Definitely avoiding cruise control too... It's just sooo much fun to drive, I wanna take it for a drive up the coast and see what it canr really do! I guess I have to wait till I hit 1K though.
 

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Daniel -
As much as they try to keep the harmonic vibrations out - there are still some there that can be a problem.

One example: On some engines the engine bolts need to be torqued exactly right otherwise they can break if the engine runs too long at a specific RPM.

Another example: Vibrations can cause wear on the wheel bearings. It doesn't matter what RPMs, rather the speed of the car.

When the car is brand new (not yet broken in) they want to ensure that things are wearing "evenly" until everything is "seated" properly.
 

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Sambusik and Teg, if you keep it below 4k RPM it should be fine. At 4600 miles it run very smooth and quite, during my break in i did 70 and below. Good luck with the break in period, I know it's tough.
 

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I question the whole breakin thing. Is there any statistics that support a hard breakin = increase incidents of repair?

Of course, there is no downside to taking it easy for the first K...

------------------
cardinal
'01 Silver/Black
LS, LD, HH, SR, 17"
 

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I too was wondering about break-in. I just picked mine up 3 days ago. I babied the thing for 2 days, but on the 3rd day, got too tempted to race an Audi. It had 300 miles at the time before the race- full throttle, four times to over 90 on the freeway.

My question is, did I ruin my proper break-in procedure, I hope not???

[This message has been edited by csdstudio (edited February 03, 2001).]
 

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Congrats on the new purchase!!!!!!!!! I also read the owners manual and tried to follow the RULES. however i was always traveling @ 85mph, but i did keep it under 4k rpms. I now have 1200miles and have finished the breakin period. The motor is smooth and the car JAMS. Moral of the story, be kind to the motor, slow accleration and be patient. Good things come to those who are patient.


Originally posted by sambusik:
Hey guys,
got my new black IS300 four days ago. Was reading owner manual and it said not to take the car over 55mph for the break in period of 1000 miles.
Dealer told me to drive it as you would another car just keep the rpm's low...

I've been careful not to let the car go over 4500 rpm but have coasted at 75 mph on the highway...

any thoughts on proper break-in?


------------------
Yellow IS300 w/LSD and graphite polished rims
 

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Discussion Starter #13
damn!! this thread is from last September! how the hell did it make it back to the first page ?


Well, I have 7200 miles on the car now. It's pretty broken in.
 

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Originally posted by civic Si-r:
...be kind to the motor, slow accleration and be patient. Good things come to those who are patient.




Do you , or anyone, think I've harmed my engines capable performance by a couple of full throttle runs at 300 miles? Thanks.
 
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