Is there a break in period before I can tow?

[georgialawn88]

I am buying a new 2017 f250 0 miles on Friday. We leave out for a 3 hour tow 8700 lb travel trailer 6 days after that. Is there a certain mileage I should but on this before hooking and towing?

[joshuajim]

Two things. First, manufacturing tolerances are light years better than they were years ago. There is little need to “wear in” the parts. They are right from the start.

Second, look at the tens of thousands of contractor trucks on the road. Many contractors get a new fleet pickup, hook up an overweight trailer on day one and tell a laborer to get to the 30 minute away job site in 20 minutes.

Rarely have I seen a failure in the 39 years I’ve been a licensed general contractor. And when they do, warranty has covered the problem.

[time2roll]

With all the comments to change the motor oil at 3000 or less miles I would think the same people would claim you need 5,000+ miles of special controlled break-in miles before you tow.

RTFM

[Community Alumni]

Yes, gone are the days of engine break ins, special motor oil, and the need to change gear oil at the end of the break in period. To this day all manufacturers still find it necessary to carry the same 500-1000 mile warning. It could be valid or it could be outdated, I don't know. All I know is if I just spent a pretty penny on a brand new truck, I'm not going to explicitly do the opposite of what the manual says and risk damage to my truck.

[Huntindog]

proxim2020 wrote:


I would caution you against comparing your F250 to a class 8 rig. Compare how many quarts your diff holds to the gallons of a class 8. The ring gear alone weighs every bit of 50 lbs. The big boys are built to take some abuse.

Yes BUT... The big rigs tow 80K or so. It is all relative
In reality, gear mating is a relic from the past.
When machining wasn't as good as it is today, and installation wasn't either.

Installed properly, the gears will be matched with no mating needed.

Proof is in the magnant. In the past, it was common for there to be metal on it, especially at the first fluid change from the mating during break in. My last trucks, and the one I regeared myself 10 years ago have had very clean magnants.

Just as motor production has improved to the point where break in isn't needed anymore, so has the gears.

Remember the days of break in oil? It doesn't even exist anymore.

[Community Alumni]

The break in period is for the gears and all new gears need to be broken in no matter the size of the vehicle. It's all about heat. Tons of heat is generated as new gears try to marry to each other within the first few miles. The amount of heat generated during the initial break in period, even from normal driving, can easily exceed normal operating temperatures of the diff.

This excessive heat can cause the oil to degrade and place unnecessary wear on parts, especially on the ring and pinion. Towing during the break in period just makes things a lot worse as it causes even more wear and heat to be generated. This could result in the complete breakdown of the lubricant and the failure of parts. Sometimes the failure isn't immediate with failures showing up thousands of miles down the road. The damage has already been done and can't be reversed. Often people think it's just age related wear, but really the diff has been damaged since day 1.

Follow the manual, but it's always a good idea to baby it for the first few miles, keep the trips short, and allow cooldown time between trips. This will prevent the diff from overheating and give the oil a chance to cooldown. It's not a good idea to try to do the whole break in all at once as this can result in a condition where the diff keeps getting hotter and hotter and eventually degrading the oil. Don't drive it like you stole it. You just need to modulate the RPM just as you would in normal driving.

I would caution you against comparing your F250 to a class 8 rig. Compare how many quarts your diff holds to the gallons of a class 8. The ring gear alone weighs every bit of 50 lbs. The big boys are built to take some abuse.

[Maury82]

jfkmk wrote:
With my F 150, Ford recommended 1000 miles before towing.

Same here...1,000 miles.

[Samsonsworld]

Lynnmor wrote:


Those that say things like "drive like you stole it" have no clue about how things work. Metal surfaces will mate better if allowed to run with little force exerted on them.

Nobody has ever worn parts to make them mate better.

If parts wore in 500 miles, can you imagine what they'd look like in 50,000?

[Huntindog]

Having built a few rearends, I would not be too concerned about the "truck" full floater rearends. They are built along the same type of designs as the big stuff, which is worked from day one.
Now the 1/2 ton rears are basically heavy duty car rear ends. Those should probably be babied a bit.

[Tom_Barb]

All motorhomes that are built on pre-manufactured chassis are loaded up and go from day one.

Most of the Class C motor homes use the same differential as 3/4 and 1 ton trucks. loaded and go from day one.

[Lynnmor]

ol' yeller wrote:
I will also join the ranks of those who say, follow the owner's manual. That said, I wonder about new Class C RVs. They are brand new too. A manufacturer straps on a house to the chassis and then a hauler drives it sometimes 2,000 miles to the dealer. I doubt the hauler follows break-in recommendations.

You forgot that they often tow a trailer as well. Go to a RV show and you will find that dealers use "new" motorhomes to drag their trailers there.

Those that say things like "drive like you stole it" have no clue about how things work. Metal surfaces will mate better if allowed to run with little force exerted on them.

[ol__yeller]

I will also join the ranks of those who say, follow the owner's manual. That said, I wonder about new Class C RVs. They are brand new too. A manufacturer straps on a house to the chassis and then a hauler drives it sometimes 2,000 miles to the dealer. I doubt the hauler follows break-in recommendations.

[Ralph_Cramden]

Bobbo wrote:
Like has been said over and over in this thread. All the information we have is what the manual says. We can choose to follow that information, or not. Most people who don't follow the manual's recommendations have no problem later. However, if you are the unlucky one who does, the fault is entirely yours.

I tend to baby a new personal daily driver, but when we buy or lease one of our company trucks its pulling heavily loaded tool and equipment trailers the day after it pulls into our yard. Our workers who are not known as the most careful individuals are very good at breaking things in lol. Never have had a rear end issue on any out of more than a hundred of all 3 flavors, but they broke about everything else you can think of and usually in short order lol.

That being said if I had to, as in no choice due to whatever, I would buy a new truck, hook up and go, and certainly not lose any sleep over it.

[colliehauler]

I guess I'm one of the unlucky ones, my previous Dodge I had to replace a noisy ring and pinion. I replaced them with 4.10 gears.

On my new Ford I did not tow until it had 500 miles on it, what the owners manual recommended at the time.

I choose to believe a automotive engineer over unqualified individuals. IF you do have a issue who do you think will pay for repairs if it's out of warranty ?

Your truck your choice.

[Bobbo]

Like has been said over and over in this thread. All the information we have is what the manual says. We can choose to follow that information, or not. Most people who don't follow the manual's recommendations have no problem later. However, if you are the unlucky one who does, the fault is entirely yours.