Opinions on max speed during break-in

I bought my 2005 Silver Prius in Springfield, VA on Dec. 23, 2005 with just 4 miles on the odometer. I flew one-way to Reagan National, took the Metro to Springfield, VA and the dealer picked me up there.

A "gentle" break-in period was not an option as I drove home to be in South Florida by Christmas.

Well 17 hours and 948 miles of Interstate driving on I-95, at speeds varying from 55mph to 75mph, with little brakes application and I was home for Christmas.

It was not an "ideal" break-in period, but it does not seem to have noticably harmed the operation of my Prius. I have 14, 000 miles now and have followed the 5, 000 service intervals. Daily commute is 75 miles of driving on I-95. Gas mileage has been 48 - 52 mpg, since the "marathon break-in" trip (948 break-in highway miles average was 50 mpg).

My wife got a 2005 Driftwood Prius in March and break-in has been all city driving. Operation of both Prius seems to be identical. She just had the 5, 000 mile service, and averages 44 - 49 mpg. Driving styles and conditions vary between our 2 Prius.

We both couldn't be happier with our 2 Prius, and hope for trouble-free operation of our 2 Prius as long as our former Toyotas (240, 000 miles on a 1993 Toyota Pickup and still running OK, and 125, 000 miles on a Toyota Corolla Station Wagon and still running OK).

Just Enjoy The Ride.
All The Best With Your New Prius.

 

Jeff,

I'm the same place you are. I finally picked up my new Prius last night, with 5 miles on it. As of arriving at work this am, I have 106. I live in Gaithersburg & work in Alexandria. Same deal -- I have to make this drive every day.

What I found was that I could hit traffic speeds ( 70-75) with pretty gentle acceleration -- around 1/4 throttle. IMHO, it's not the speed but the stress you put on the engine. As long as you're accelerating gently, I think you'll be fine. I'm finding that it takes very little pedal pressure to hold 70 mph, and on slight downhills, I can even get it to kick over to electric-only for a bit.

So, my advice is drive where you need to, leave yourself lots of room to pull out so you don't have to gun it, and just be gentle in general.

I hope you like yours as well as I like mine!

dave.

P.S. -- my overall mpg for the 106 miles is 49.6, with 40 of them being highway. Great fun!

 

Agreed. Don't beat it with fast accellerations.

I think it's more important to do a first oil change at no more than 1000 miles! Oil gets lots of metal particles as the engine breaks in.

I recall the manual saying no sudden stops until 600 miles, I think thats when I'll do my first oil change too.

- have fun- I am!

 

<div class='quotetop'>QUOTE(alsgameroom\";p=\"108796)</div>

The first oil change has been discussed in other threads and opinions vary from your viewpoint to those who say it's best to wait until the 5,000 mile point has been reached for the first oil change, I forget all the reasons.
Maybe we could have a mini re-hash of them.

 

<div class='quotetop'>QUOTE(JeffHart\";p=\"108762)</div>

I had similar concerns with both of our Priuses ('04 and '05). Traditionally, the rule about engine speeds during break-in has been to avoid "sustained high speed driving." This was a) to keep the engine speeds down *and* to avoid long periods at steady throttle openings (like a cruise-control set 70 mph across west Texas!)....that was to provide enough changes in throttle to bring oil up to the piston rings and allow them to seat well. But, as someone pointed out to me, the nature of the Toyota Power Split Device and its planetary gearset will pretty much guarantee that the ICE is not going to stay at a constant speed and that there *will* be plenty of adjustments to the throttle (watch the Energy screen on the MFD at a steady highway speed and you'll see it)

Now, as to the statement your trip around D.C. will "require" you to maintain at least 65-70...hogwash. Now, I don't think you should be driving at 55 either...but I've never bought the notion that drivers are somehow victims in the crush of the flow of traffic. If you want to drive 60-65...do it. Just stay in the right lane. But it's more important that you vary the speeds. So why not just decide to do 60-65 (or even slower) only where and if you can (so as not to impede other traffic) and then do 65-70 only where you have to....but just be sure to vary things up a bit.

Also, from what I've read, concern over metal shavings from engine manufacture and, thus, the need for a first oil change at 600-1000 miles is a relic from our fathers'/grandfathers' era. While it was once true, modern methods of machining and assembly have pretty much removed the concern. The first oil change can be at the manufacturer's first recommended interval.

 

at 60-70 mph you should get around 45mpg. This is what i averaged when i recently drove from chicago to new orleans and back.

 

Yea.. does anyone know what the deal is on sudden stops?... why is this bad on breakin?..
I've never seen that warning on normal cars?

Is it the engine or the electronics or what thats at risk?

 

I don't know about DC, but if you drive in Florida, you better be 80 or above or you will get the car behind you on your tail "5 feet off your tail flahing his lights!".
I was going 82 and traffic was passing me and a stater passes me non emergency.. they were just cruising!
He didn't pull me over because he would have had to pull eveyone over too!

Down there, you don't even raise the staters eyebrow unless your over 90.

I think 90 is the official cruising speed and much of that will need to be in the right hand lane as many go even faster.

 

My understanding on the heavy braking prohibition regards the rotors. They get HOT! and heavy braking gets them hotter. Wwithout a break in period for them they can warp. A warped rotor yields a pulsation in the braking when the mechanical brakes are used.

Another reason not to worry about an early oil change... That's what the oil filter is all about, filtering out particles. Machining chips are bigger than the particles the filter is designed to catch, and will stay on the surface of the filtering media. They won't clog your filter, the oil will pass around them. Old, and todays cheap filters filter on the surface, but the Toyota filter I saw the inside of has filter media "in depth" (a better filter), so chips aren't a problem for it.

 

My break in was from Salt Lake City to San Francisco at 75 to 82 mph. AFter the 10k miles or so of break in I got 52 mpg average(mixed driving). I switched to Mobil 1 oil after the break in period.
I would change the first oil at 1k or 2k miles to dump the shavings.

 

I picked up mine in Charlotte, drove back to Atlanta. 60 minutes outside of the dealer, had it up to 95 MPH on I-85, just keeping up with the top end flow of traffic. 10,000 miles later, haven't really noticed any issues.

 

Rotor warpage should be a thing of the past with the prius, the regen does most all of the braking in most situations and friction braking never comes in until under about 8mph.. at those low speeds there is no heat....come down off a hill and see if your wheels get hot.. they shoudn't.

After 100K miles, they found no difference in the pads verses new ones!
http://privatenrg.com/#100kBrakePads

 

Check out this method of breaking-in http://www.mototuneusa.com/break_in_secrets.htm

Seems to be the opposite of convential thinking. What do you all think?

Andy

 

I think "break in" is a holdover from the Good 'Ole Days. Just drive it. I treated my new 1984 Ford F-150 V8 to a "special" break-in - speeds under 50 MPH - and I think it benefited. That thing is also crude by any measure, at least the assembly was.

My 1990 4Runner I just drove it at whatever the posted speed limit was and changed the oil/filter at the regular oil change interval. When I sold it in 2000 for my GMC Sierra (Big mistake!) it had around 380,000km on it. It ran perfectly and used about 1 qt of oil every 10,000 miles.

My 1992 Honda Prelude SR I also drove normally and changed the oil at the regular interval. I only had 78,000km on it when I sold it in 2000, but it also ran fine with no oil consumption. I still miss that coupe ...

My 2000 GMC Sierra started the infamous Vortec knock-knock at 5,000km. Junky thing. GM dealers locally recommended the first oil change at 3,000km or 3 months, then whenever the Oil Life Monitor recommended.

 

I followed the advice someone posted from this website. It makes a lot of sense:

http://www.mototuneusa.com/break_in_secrets.htm


I had a 50 mile trip back home so I gunned my new car and breaked hard over and over on the highway. I went anywhere from 90 mph when flooring it down to 60 mph when breaking. A few days later with 80 miles on the odometer I put conventional oil in the car.

So far I have 600 miles on my car, and it runs perfect. I will change to synthetic sometime between 3,000-5,000 miles.

 

I know in the old days it made a big difference... now I've always assumed the tolerances are much tighter in the name of using thinner oils to get better mpg.
Another interesting note too was

I've take the attitude of driveing normal with caution not to be excessive.
To me that means cruising at 60 - 70 if desired and occasionally going 80 for short periods.

I will not go over 80 for now and I avoid romping on the gas but I am not afraid for normal acceleration to get on the freeway or pull out in traffic... the car doesn't even seem like its working hard to do that anyway.

 

So reading this thread is it bad that less than a week after getting my Prius I will put 3,000+ miles on it on a cross-country trip?!

If I keep it under 65mph with no cruise control and avoid gunning it for the trip, will I be OK? Oh...and no crazy braking, too. Right?