Is there a break in period before I can tow?

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 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 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.

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.

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.

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 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?

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

Same here...1,000 miles.

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.