how many miles till i can do a long trip

Saddle up and go. I was told to vary my speed for the first 1000 miles but was not told of any restrictions on long trips.

Happy Motoring

 

You can do it right now. On a new Prius, try to keep the speed at reasonable levels (highway speed is okay), avoid full throttle, and try not to panic stop. Other than that, off you go on your trip.

Tom

 

Varying your speed is not really an issue, as the engine speed is independent of driving speed. The Prius control system will end up changing the engine speed with conditions. I suppose if you are driving across Kansas with steady weather it might make sense to vary your speed a bit, but otherwise it's unnecessary.

Tom

 

The thing about breaking in piston engines is the need to properly seat the rings in the cylinders, plus "run in" the crank, cam, etc., bearings (typically the reason "break-in" motor oils are less viscuous with the first oil change at 1/2 the regular interval). That "traditionally" (my training, I don't know from the previous posters) means keeping the revs low (e.g., below 4K) and semi-routinely "pulsing" (accelerate/decelerate) the engine while in gear in order to work both upper and lower "sides" of the rings, "deglaze" the cylinders, "seat" bearings, etc.

More importantly, you should be aware that this can't occur until the motor is up to operating temperatures. This is because pistons are machined in an oval shape, looking from the top, in order to accommodate greater expansion in the piston pin bolster areas causing the piston to become perfectly round, when heated. Before any substantial load should be placed on the motor (even after break-in), you thereby want to bring the motor up to operating temps so all the parts (pistons in cylinders, piston ring "lands" matching piston rings, crank/cam/etc. bearing surfaces, pump clearances, etc.) are all at their design specifications. You always want to avoid "winding out" a new "tight" engine until the internal moving parts have been given a chance to "seat".

All that being said, the above (other than proper warm up) is much less important with the Prius, except that cruising at constant speeds won't help with ring break-in. Plus, when the IC goes off-line you don't get the in-gear deceleration effect (won't go into why this is), since it just disengages and turns off. I would suggest frequently using engine braking (keeps the IC in gear) for the first 600-800 miles to accomplish this, but only below 40-50 MPH to avoid mechanically over reving the engine.

So why have you never heard of this? Because it's not that critical, as most folk's driving styles mimic proper break-in patterns, plus the explanation is "scary" - not a good thing for marketing. The few "crazies" out there who continually red-line their cars right out of the dealership and thereby limit the ultimate performance/life of their engines probably wouldn't take care even with an explanation.

But we are lucky Prius owners who have not only one, but two electric motors to help keep "real" engine loads down. Even at a constant 80 MPH, unless you're driving in mountains, you should never see much above 4K RPMs which is pretty low (I never saw over 5K driving between CA and Pikes Peak, last year). Since our engines rarely see undue "strain", properly maintained, they should last for many more miles than their unaided peers. Bottom line, I wouldn't worry too much about it. Maybe limit your sustained cruising speeds to 75 and not "push" it on long uphill grades. Optionally, during the break-in period, when decelerating from 40-50 or when driving less than 40, keep it in engine braking mode (won't help mileage, though) - but that's only if you want to be a "purist".

hope this helps!

 

I bought mine w/61 miles on it, took it 700 miles round trip that weekend with cruise control set at 75. Not a problem.

 

Gary, that's BS in its purest form. First, the Prius ICE is well machined and run in at the factory, so all the discussion of seating and run in during a break-in period is mostly bunk. Second, the motors are spinning the ICE in B mode most of the time; it's mostly playing with valve timing.

Remember that the Prius is designed to be a low emissions car first, great MPG is just a byproduct. The computer controls the ICE and motors for minimum pollution.

 

With the exception of some heavy duty diesels - like those used in Kenworth, Peterbilt, and other big rigs - I'm unaware of any modern gasoline motor that "requires" an elaborate break-in procedure

How about in the EU, especially Germany? I have this mental image of a person from the States driving a brand new BMW onto the Autobahn and poking along the rightmost lane at 70 km/h. Yeah right, they fly along even from brand new, no ill effects

However, that "break in" procedure IS necessary if you take something like an old small block V8, and rebuild it the "old fashioned" way: no CNC equipment, no align-honing, no deck plating, no roller lifters (Old motors had flat tappets), no hypereutectic pistons, no moly zero gap rings

I'm planning on building up a 1967 Chevy C-10 pickup sometime in the next year or so. The stock V8 motor for such a thing was a 327, but a 350 is the best drop-in replacement.

There is no way in hell I would even think of rebuilding a motor myself, the few times I've done so I've had so-so results. A modern crate motor made with modern CNC machinery is light years better than the old fashioned way

So long story short: just hop in and DRIVE it!