I read the extensive thread on “How do I break in a 2012 F350 6.7L?” I’ve also read the 2020 F250 manual I was able to download. It’s obvious that opinions vary widely on this subject. Everything from “drive it like you stole it” to oil changes within the first few hundred miles. And there was quite a bit of variance from the simple instructions in the manual - which suggests varying the speed for 500 miles and not towing for 1000.

I’m simply asking this of our knowledgeable diesel owners and techs: 1) Have break-in procedures and recommendations changed from the days of those posts back in 2012? I’ve not read the 2012 manual, but the quotes sounded pretty much like the 2020 manual. 2) Does the use of full synthetic change anything?

 

Just do what allows YOU to sleep good at night. RTFM and enjoy........life is too short to worry about these things. By the time this ends, you will be totally confused, because answers will be all over the board.

 

Just vary the throttle the first 500 miles. try to not maintain a set rpm. try to not use the cruise control. These are what I did with my 2015. Once I hit 500 miles, it was drive it like I stole it.

 

With the 10spd it is really easy, even allows you to set cruise if you have a long drive back. Just lock out higher gears every 5-10 minutes. Can maintain the same speed and change RPM's a lot between say 6th and 10th. That is how I broke my '17F150 with the 10spd in, did the same with my Mustang and a stick but of course only had 3 gears to play with there. 5 min's in 10th, 5 in 9th 5 in 8th, back to 10th then down to 7th etc etc. If you aren't doing a long highway drive then just drive it. I change oil a little early, 5K at the most and 3K if possible, probably not needed but is pennies in the grand scheme of owning for 100K mile or more.

 

I've had a new 2000 7.3L, a new 2003 6.0L, a new 2006 6.0L, a new 2011 6.7L, a new 2015 6.7L and now a new 2017 6.7L.
I ran each truck 100,000 miles and the 2011, I ran 150,000 miles.
My 2003 had a tranny failure at 3000 miles. other than that, I've not had a failure of anything oil touches.

I usually change the first oil at 5,000 miles. ( 3,000miles back on the 7.3L and 6.0L)
On the 7.3L and 6.0 I changed the oil every 5.000 and on the 6.7L I change the oil as the Oil Life Monitor prompts.

I usually try to drive 500 miles with out towing. First tows I try to not tow hard. meaning no 7% hard climbs with 13,000 lbs behind. But the 2011 6.7L I hooked up a dump trailer hours after I left the dealership. I had work to do, and mine are work trucks

I can't speak for how these trucks held up long term other than the 2000 7.3L which I sold to friend and he ran it another 100,000. He beat the body up something terrible in his construction business.

So like the above post. Drive it respectful of being new. give it as much time to break in as possible. Don't go out full pedal to floor the 1st 500 miles and these trucks seem to run just fine

 

I have heard it is a good idea not to heavily load the gears in the transmission or rear end for 500-1000 miles while they work themselves in, but I don’t know if that’s old school lore and still relevent.

 

Wow - appreciate that advice. Obviously you’ve squeezed the work out of those trucks - and they’ve been reliable. Encouraging. What do you do - sleep going up and down the highway?

 

I varied the speed, no full throttle starts until I hit 500 miles.

Towed at 75 miles on the odo, but tried not to be too hard on it.

 

You are correct on the gears. it says the same thing in the book. Its hard to wait the 500 miles though LOL. As for oil changes. There is no such thing as brake in oil anymore. These motors are built so much different from motors in the past and the materials used are so much better that you don't have to brake them in. I do agree with Just Stroking just very your RPM's and after 500 you don't have to worry. It's nothing that i personally did to mine. I did however not use cruise control at first. I also found that cruise doesn't give you the best fuel millage. Even on a long road. I hardly even use mine

 

I have heard that fleet vehicles are loaded down at/near to max GVWR/GCVWR from the beginning and then are put to work. The engines are derated but I don't know if there are any software transmission changes I'm sure the hardware is the same.
I think new owners are good with break in or not breaking in. But if something goes wrong with the powertrain before break in period ends I'm sure the dealer services dept will take that into consideration.

 

The 6.7l doesn't fully break in until 12k miles or so. The manual stating not to tow for the first 500 miles is most likely for the rear end gears.

 

I put 300 miles on my 2020 then hooked up the camper and started towing. Deere says to work them hard from the start to set the piston rings so that's what I do with all of my diesels

 

FORD advertising........”WE OWN WORK”!!!
FORD lawyers and bean counters.........don’t work it or it might break and be on FORD!
LOL

 

A little side note on this thread that started with my question about best break-in practice on the 6.7. I’m at 293.8mi on the odometer. It had 8.6 mi on it when I picked it up - and the dealer had filled the tank (34 gal tank). I drove it home, and around town doing some errands - 51 mi. Then I took my first trip of 242.6mi. Fuel gauge is still at about 55%. It says I have 428 mi to empty. Fuel economy shows an amazing 19.8 mpg! I know...I know, I’ll have to fill up at a near empty tank to know the real deal. Furthermore, I’m babying through the first 500 break-in miles - not like I usually drive. Trip driving I varied (like recommended) speed from 60 - 80 mph. My point is, I never expected that kind of mileage. If I babied my F150 EB I couldn’t get much more than that. And it’s not yet broken in. Bottom line, anything over 15 and I’m happy in the real world.

 

One of the many perks of the 10 speed. That MPG sounds great.