And to pee in everybody's wheaties, I am skeptical about being able to "wear-in" a hardened gear set in 1000 miles. If one can "wear" them in in that short of time, by the time one has 2-3 hundred thousand miles on the vehicle, one would have had to replace several worn out gear sets that have been reduced to powder......hook it up, put it to work, that is what they are for!!! The last new big truck that I "broke in" had 50 miles on the odometer when I loaded at a terminal, to 110,000 lb GW, and put that 1000 miles on running across Montana and Wyoming (not all one load) in July with ambient temps at 95-100 degrees F!!!
Work it like you stole it!! With my '16, F350 DRW, I drove it approximately 350 miles from dealer to where my loaded 38 foot gooseneck was sitting, hooked up, drove from Western ND to Phoenix, dropped off a few things, then from Phoenix to Northwest Arizona

 

I did the chicken-ship route and got in my 1K prior to pulling. Whether it works or not, it's easy insurance to that "What If". One less thing to worry about and TBH folks, it was fun making excuses to go on these semi-local 100mi lunch runs... to somewhere normally we'd never go.

Plus I had my Farkle-days (installations) during this period. Always a good excuse to drive to an RV show b/c you just installed the tonneau and you have to try it out! (wife bought the idea!).

So make it fun, break it in with constant up/down RPM's, use the engine brake and manually downshift also.

Generally as far as warranty or correct break-in period goes? If it works, it works!... if it doesn't?, it was sure fun doing it!

 

There's a member of another forum who plugged in a hitch with an electric ornament of some sort on it. The truck recognized it as a trailer and has logged ALL of his miles since the day he bought it as trailering miles, however, he has never has a trailer hooked to it yet.
I guess a fellow could use this excuse if he had a problem with Ford in this regard.

 

I wonder how much information is stored or captured? Guess if the mileage is captured then they would know if there was a trailer or not.


EDIT: I meant MPG.

 

Its a good question. Mileage is captured, but even Ford must know that its hardly accurate...if you uncouple and keep driving, the truck continues to record trailer miles even though you don't have one behind you.

I guess it could potentially record brake applications, trailer light faults, etc.

 

Not so sure the 'break-in' period is for durability as much as it is for drive train noise.

 

I can't think of anything to 'break-in' on the new engines these days.

The cams are of the roller variety and the rings seat in about the first five seconds of running. Okay, maybe the first twenty minutes.

Crank bearings? Not. Rod and/or wrist pins? Nope. Mains? Not today

Are things a little tight? Yup. Is it still what we call a 'green' motor? Yep.

Just don't don't beat it, don't dog it and you should be fine.

I've always believed in getting the factory oil out as soon as practicable (first 1 or 2k), but I think that's just me being obsessive. Or not. I think any new/green engine puts micro-sized bits of metal into the oil simply because it's nice and tight.

Again -- Just me.

People wonder why their Old Grey Mare ain't what she use to be and it's bad oil change intervals and practices IMHO that cause it. My old vehicles ran just as strong after 80k as they did when new.

Diesel or Gas, the principles are the same. Common sense prevails

 

I worked for a drive train manufacturer for 9 years and agree with you on this. I never heard of a break in period for the gear set until I started reading this on forums. The ring and pinions are hardened after machining and then ground and finally lapped as a matched set to determine proper shimming for assembly after setting the contact patch on the drive and coast sides. After assembly they are tested for noise and proper gear ratio then dropped in the carrier. It would take some serious heat for an extended period of time to change the hardness on them. I think ours was at least a 14 hour period from when the gears went into the oven before they finally came out of the draw. Can't wait to hook mine up to the fiver this weekend for its initial pull.

 

Randy's explains it pretty well:

https://www.ringpinion.com/Technical...r_break-in.inc

From the above link:


Do we really need to break in a new gear set? I have heard many people say "When I bought my new truck, no one ever told me to break in the ring & pinion." Whenever we are blessed enough to afford a new vehicle, we take it easy on the engine for the first few hundred miles. While we are pampering the engine (probably for the last time ever), the ring & pinion set goes along for the ride and gets a chance to break in before we hammer the throttle.
In most stock vehicles with stock tires there is seldom a risk of a burned gear set. For those of us who modify and use our trucks, there many situations that can contribute to burned gear syndrome. Motorhomes, towing, tall tires, and high numeric gear ratios (4.56 & up) can all generate a lot of heat and cause the gear oil to break down. The greatest damage to a new gear set results from running for ten minutes or more during the first 500 miles when the oil is very hot. Any heavy use or overloading while the oil is extremely hot will cause it to break down and allow irreversible damage to the ring & pinion.

In order to make them run cooler and quieter, new gears are lapped at the factory. However, they are not lapped under the same pressures that driving creates. The loads generated while driving force any microscopic high spots on the gear teeth back into the surface of the metal. This is called "work hardening". Work hardening is similar to forging in the way that it compresses the metal molecules into a very compact and hard formation. This can only be accomplished if the metal surfaces are lubricated and the gear temperature stays cool enough that the molecular structure does not change. If the temperature of the metal gets hot enough to change the molecular structure, it will soften the surface instead of hardening it. This may seen like a balancing act, but it all happens easily and passively as long as the oil keeps the gear cool while it is breaking in. Some of the synthetic oils on the market today can help a gear set live longer. I've had great success with Red Line ®, Torco ®, and Richmond Gear ® synthetic gear oils. These oils will continue to lubricate at temperatures where many crude oils break down.

Even with synthetic oils, I still recommend the following procedure for breaking in a new gear set: After driving the first 15 to 20 miles, stop and let the differential cool before proceeding. Keep the vehicle at speeds below 60 mph for the first 100 miles. I also recommend putting at least 500 miles on the new gear set before heavy use or towing. During the first 45 miles of towing, it helps to go about 15 miles at a time before stopping to let the differential cool for 15 minutes before continuing. This is necessary because not all of the gear tooth is making contact until it is heavily loaded. When towing, the teeth flex to contact completely, and cause the previously unloaded portion of the teeth to touch and work harden. It is very easy to damage the ring & pinion by overloading before the teeth are broken-in. If you take it easy on a new ring & pinion and keep it full of high quality oil, it will last a lot longer.

With regards to limited slip additives, I have found that using too much additive can lead to premature gear wear. Use just enough to keep the limited slip from chattering but not more than 4 oz for every 2 qts of oil. It is a good idea to change the gear oil after the first 500 miles in order to remove any metal particles or phosphorus coating that has come from the new gear set. This is cheap insurance and a good time to discover any problems before they grow too big.

 

I don't really buy into the breakin except for maybe the breaks. I think personally it's more lawyer talk and ford wanting you to get comfortable with the truck before hooking it up to a big trailer but that's my opinion

 

Hook it up and roll. 6000lbs is a bite size Snicker bar to a SD!

 

This is why I love this community. I'm going to do my best to put 1000 miles on her before towing... then again if the weather is right we need to get to the lake for some early season surfing!!

 

This is my plan as well, do my best to follow the recommendation, but I know I will need to be towing over 13.5K by mid-June (if not sooner) and don't even have my truck yet, so don't think I'll make it to 1K first, lol.

 

My truck is supposed to be delivered tomorrow... for the second time. We'll see, I try not to get my hopes up because Cotus likes to mess with me!

 

At least COTUS talks to you. Most of us get the cold shoulder... LOL