Car Break-in Period

Hi All,

I just bought a 2011 Elantra and I love it. But around all the excitement, I completely forgot about the break-in period instructions for about a week. Neither the sales guy pointed out nor I bothered to look at the manual after taking the delivery. During this week, I had once put my car on idling for about 20-30 mns while I was clearing out the snow off my car (The manual says not to put the car on idling for more than 3 min at one time). I had also put my car on cruise control (at about 70 mph) several times during the week. I probably did not obey the break-in period rules for about 250 miles during this week. I am overly worried about this and wasting too much time reading about this. Do you guys think that I have already done some damage to my engine? Now, I am taking cross-roads to work, varying speeds and trying to do my best. Also, the manual says avoid driving at constant speeds for long periods of time. How long is long periods of time? Can’t wait to hear from you all. Thanks in advance.

Just drive normally. I have seen a Hyundai leave the dealership and put immediately into service on a rural mail route and was still running trouble free at 300,000 miles. Another was bought by a local drug store for in town delivery and they have worn the windows out but the engine keeps running. Check your fluids occasionally, service it regularly and quit worrying.

I wouldn’t spend too much time worrying about this. I suggest you read the ENTIRE owner’s manual, however, and follow its advice regarding future maintenance.

Your engine is pretty much broken in within the first 20 miles although it’s a good idea not to take it easy for the first 500-1000 miles. From what you state in your post I don’t see anything abusive there and you should be fine.

The reason why car maker make statements about an extended break-in period is because in the right circumstances a select few owners are going to beat their new cars into the pavement from the get-go. This could lead to engine problems for which the car owner would get a warranty repair as abuse would be hard to prove.
Every new car that rolls off the assembly line has a set amount budgeted for warranty repairs and warranty engine work will mangle that budget, along with possibly digging into the budgets of other new Elantras.

Your car is fine. Read the manual and pay particular attention to the scheduled maintenance section. If the manual doesn’t say to change the auto transmission fluid every 30K miles, then add that interval to your maintenance routine. That will keep your car going, and going, and going. Don’t worry, be happy!

Don’t worry too much about it. There’s a small chance the engine will use a little more oil when it’s older than it would have otherwise, but that’s not a big deal.

As for the constant speeds, here’s my opinion. When you’re on the highway, avoid using cruise control and alternate between two slightly different target speeds (like 67 and 70) every fifteen minutes or so. If you’re making a long highway drive, consider getting off every now and then and using a side road to get to the next exit. Even this is probably overkill, but I’ve never minded doing these steps with my cars when they were new.

ok4450, I had the same question as the OP about how long is too long to run at a constant speed and why is constant speed to be avoided?

When a manufacturer states “not to run at a constant speed”, they basically mean not to get on I-70, set your cruise control to 70 mph, and then drive from Limon, CO to Indianapolis, IN to complete your break in run.

If you have a 20 mile highway commute, you can set your cruise control for the whole time, and not worry about anything.

The main thing they want you to do is get the piston rings to seat well, and that takes gentle warm ups, and not being afraid to use the throttle, to run the engine up through the rpm range. This will give you the best compression numbers your engine can make, and give you a nice, powerful engine. Tight engines are better, emissions wise, too.


Thank you all so much, that makes me feel so much better.

Yeah I wouldn’t worry about it either although I meticulously follow the break in instructions except for the oil change. I just can’t leave the oil in for 5000 miles. I think probably 60-70 of the people buying cars either can’t or don’t read the owner’s manual anyway.

Judging from this message board, it is more like 98%. But then again, if people read the manuals Tom and Ray would not have much of a show, would they?

While I have stated that a lot of people are guessing on oil changes, to some extent we are forced to guess on a lot of things. The manufacturer simply does not explain the recommendations so we can make optimum decisions.

They are correct to the extent that the majority of owners don’t even have the capacity to make a good decision even with adequate information. Those who come here probably do.

While on oil changes, I can get solid data with an oil lab test, in many areas I am also forced to guess. I believe those recommendations are made on a statistical basis, estimating how much the average driver will drive the car before trade-in, and under what conditions, etc. If I want to drive my car longer before repairs, I may want to increase maintenance in some areas.

We bought our new 2002 Sienna right after 9/11. We knew in a few days we were going to drive across the US at 70 mph on cruise control. So, I took my car out and drove it up and down on secondary paved roads north of McAllen, every day to get that 1,000 miles of varying, modest speeds.

The manual said this was necessary for engine break in. At the end of the 1,000 miles I had the oil changed at the dealer. That was the last time. They used Pennzoil, which is not Genuine Toyota parts, as they advertise. The guy got an insulting look on his face when he realized I was changing the oil at 1,000 miles.

My viewpoint is they are either lying about the break-in, or I want the break-in stuff out of my motor, period. I do not want to drive a new engine which has worn stuff in the oil and/or filter.

So, I guessed, and still have no more information to contradict my decision. I realize other people will guess differently. I do not wish to convince anyone to make the same decision, because I know I don’t know.

If I ever get another new car, I will do the same thing, except I will go to synthetic oil on that 1,000 miles, if it didn’t already have it.

Someone once said, not to use synthetic oil until the car has a lot of miles, or it won’t get broken in. I believed that. But, one day it came to me. If synthetic oil keeps it from breaking in, then synthetic oil means it doesn’t have to break in. If you don’t understand that, think about it a while.

The only way synthetic oil makes it run so smoothly that it doesn’t break in, then it means doesn’t need to be broken in because it is already running smoothly.