Just got new 04 F150. Manual says don't drive at constant speed for first 1000 miles. that is all it says about this. Heading on 600 mile trip. How much do I have to vary speed? by 5,10, 50 mph? How long can I stay at one speed: 3 min, 10 min 30 min? Do I really have to do this for 1000 miles or is that an exaggerated safe number and maybe 200 miles would work?
Did a google search and found lots of opinions but not the specific info I am asking.
Ron,
You really should follow their break-in advice, but it isn't that hard. I'm sure you'll make stops and slow down for construction on your trip.
Just vary your speed about every 30 to 60 minutes, and it'll do fine. Also, once in a while, maybe while climbing a hill, give it a *short* burst of full throttle. That will help seat the rings.
A motor's break-in period is much like a child's rearing. It makes a big difference on how it turns out.
John
Not bad advice. I would add that you should change your oil at 1000 miles or less. You will get rid of lots of large particles from the rings and cylinder walls breaking in. You can see these in your oil in the sunlight if you take a look.
With the varied speed, it changes the pressure in the cylinders. when you accelerate hard, the pressure in the cylinders pushes the rings against the walls making them machine eachother to fit perfect, then when you take the foot off the gas, the pressure drops, and oil passes the rings and washes away the metal partials. If you just hold it as a steady RPM, you run the risk of glazing the rings and cylinder walls, and not making a good seal. I would think the first 200 miles would be the most critical. but the full
1000 miles sounds about right for a good break in.I'm sure someone here can expand on this some more for you. but that is what I have been told.
Isn't there a magnet in the bottom of the oil pan to catch any metallic residues?
-- "When you argue with a fool be sure he is not similarly occupied."
See how the Pros get more POWER!
Most of the particles are in the filter. I changed the oil after 500 miles in my recent 300 six rebuild. In the sun, the oil almost looked like metal flake paint. But most was in the filter. This is normal. Myself, I keep the filters after the first few oil changes. If you have en engine issue, they can analyse the oil and see if the problem was there from the start. You can do this yourself if you just want to check the overall condition of the engine. Oil analysis is fairly cheap. As far as break in, Don't hold a steady speed for too long. Try to vary a bit as often as possible if on the highway. Do healthy takeoffs, with good throttle to help seat the rings. When you let off the gas doing a high speed, let the engine power brake if possible. This draws oil up into the cylinders which is good. It's easier to do this with a manual than an auto...Don't go at too high a speed until you get about 1000 miles or so. If you have an overdrive, turn it off and on every once in a while to vary rpms if you need to on the road. Myself, I like change the oil at 500 miles for the first time.
1000-1500 miles for the second. After that, you can pretty much do as normal. MK
Thats pretty much it. Letting off the gas and letting the oil draw up into the cylinders is as important as seating the rings with healthy throttle jabs. You want to engine brake a lot when decelerating. MK
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.