Engine Break-in Procedures

**ependydad** · 08-06-2018, 02:10 PM

The new truck should be here in the next week or two. So I decided to do some reading of the owner's manual for the 2018 Ram that I have coming. Here's what is recommended:

Quote:

ENGINE BREAK-IN RECOMMENDATIONS
A long break-in period is not required for the engine and drivetrain (transmission and axle) in your vehicle. Drive moderately during the first 300 miles (500 km). After the initial 60 miles (100 km), speeds up to 50 or 55 mph (80 or 90 km/h) are desirable.

While cruising, brief full-throttle acceleration within the limits of local traffic laws contributes to a good break-in. Wide-open throttle acceleration in low gear can be detrimental and should be avoided.
---
Towing Requirements
To promote proper break-in of your new vehicle drivetrain components the following guidelines are recommended:

Do not tow a trailer at all during the first 500 miles (805 km) the new vehicle is driven. The engine, axle or other parts could be damaged.

Then, during the first 500 miles (805 km) that a trailer is towed, do not drive over 50 mph (80 km/h) and do not make starts at full throttle. This helps the engine and other parts of the vehicle wear in at the heavier loads.

Found here:
https://www.mopar.com/moparsvc/twedd...cations?id=246

The 500 miles of towing at or below 50mph is incredibly surprising to me.

**KyDan** · 08-06-2018, 02:27 PM

Personally- I would not stress over that 50 mph part of the trailer break in.
If you need to tow during that time do it. Just drive a little more moderately. I would not hesitate to go 65 on the flat but I would just take my own sweet time to get up to that speed.

Not really comparable but I bought my new Titan Gasser on Dec 23 and towed my rig to Florida mid January. It had about 350 mi on it when we pulled out of the driveway with the trailer. It was 8 degrees! I'm pretty sure not much got over heated!! We reached the 500 mile break in period by the time I needed to stop for gas and a p ... er .... restroom break!

2Evil4U · 08-07-2018, 07:55 AM

Chatter on the Cummins forums is that that break in period is mainly for the gears in the axles. Desirable, rather than mandatory is their weasel word. Supposedly the motor is basically good to go from its factory. I'd just go a bit easy on it for the first 500 then drive it like you stole it.

goduc · 08-07-2018, 09:09 AM

On my 2012 Ram 2500 CTD I did the initial 500 mile break in. Then hook up the 9000 lb 5er and went camping. No way could I only go 50 mph. I took it easy for a few trips. 59,000 miles latter and zero rear end issues. Not to say that at 59,001 miles something could go wrong. But I highly doubt it.
I did the same with my 2018 Ram 6.4.

MillMitch · 08-07-2018, 09:23 AM

interesting post. for me, it begs the question, what if you buy a used vehicle. Presumably if it's never been used to tow, you would need to adhere to the first 500 miles of towing guidelines.
Which i haven't done, and am now concerned about.

Lins · 08-07-2018, 09:43 AM

Yes the break-in is supposedly for the gears. Do a few heat cycles of the rear end if possible then drive it like normal, not crazy and you’ll be fine. Check the plug occasionally if you can. I found a lot of metal fuzz at break-in, and even large chunks probably from machining. A few people on another forum found the same or worse. I replaced the diff fluid after a few hours of towing after the break in and the gears looked great, no sign of where the metal chunk came from. Are you getting the Cummins? The manual wants you to load that engine up for a few thousand miles!

**KyDan** · 08-07-2018, 09:47 AM

Quote:

Originally Posted by MillMitch

interesting post. for me, it begs the question, what if you buy a used vehicle. Presumably if it's never been used to tow, you would need to adhere to the first 500 miles of towing guidelines.
Which i haven't done, and am now concerned about.

Where did you get that idea? If it's got anywhere from several hundred miles on up it should be good to go up to the owners manual stated tow limits.

MillMitch · 08-07-2018, 02:20 PM

Quote:

Originally Posted by KyDan

Where did you get that idea? If it's got anywhere from several hundred miles on up it should be good to go up to the owners manual stated tow limits.

Then, during the first 500 miles (805 km) that a trailer is towed, do not drive over 50 mph (80 km/h) and do not make starts at full throttle. This helps the engine and other parts of the vehicle wear in at the heavier loads.

I'm basing it on the owners manual language. It doesn't say anything about what mileage the first 500 miles of trailer towing occurs. If it was the same break in as a new engine, they wouldn't have mentioned it separately.

DieselDrax · 08-07-2018, 03:00 PM

Quote:

Originally Posted by ependydad

The new truck should be here in the next week or two. So I decided to do some reading of the owner's manual for the 2018 Ram that I have coming. Here's what is recommended:

Found here:
https://www.mopar.com/moparsvc/twedd...cations?id=246

The 500 miles of towing at or below 50mph is incredibly surprising to me.

The speed limit isn't for the engine but for the rear diff, the gears are work hardended/burnished during the first few hundred miles and during this time they can get pretty hot. The faster you drive, the hotter they get, and if they overheat then it can make the teeth brittle. So, the manufacturer wants you to limit your top speed for the first 300-500 miles and also not do any towing during that time.

Brewhedd · 08-07-2018, 03:30 PM

Also worth mentioning are the recommended full throttle applications while cruising. Very important with any engine break in as this helps seat the rings.

5er_tom · 08-07-2018, 03:31 PM

Not everyone has the opportunity to do the slow break in. We were stranded and had to buy a new truck and then continue on our journey. The new truck had 122 miles on it when we hitched it to the fiver and towed 250 miles across the WV mountains into PA.
I did try to take it easy but mountains are mountains. We'll see if this bites us in the butt in a few years. I will have the differential fluid changed at the first servicing. We now have 7300 miles on the truck.

babock · 08-07-2018, 03:37 PM

I would just follow the OEM manual. Amazing how many people seem to be smarter than the people that designed and built your new vehicle.

racer4 · 08-07-2018, 04:14 PM

As stated, the break-in is for the gears.

I did the first 500 miles of towing on two lane highway, so I could keep the speed down and varied.

I got new gears, to change the ratio, on a E-150 at a shop that specialized in ring and pinion. I was given written instructions to drive 15 miles, stop and cool for 1 hour, then drive 30 miles and cool, 50 miles and cool, then 100 miles and cool.

This burnishes and work hardens the gears.

Similar info here:
https://www.randysworldwide.com/faq/
see: Differential - What is the break-in proceedure ... about half way down.

I have a longer article written by Randy Lyman, founder of Randy's Ring and Pinion (apparently now called Randy's Worldwide), if you are interested.

**ependydad** · 08-07-2018, 06:19 PM

Quote:

Originally Posted by 5er_tom

Not everyone has the opportunity to do the slow break in. We were stranded and had to buy a new truck and then continue on our journey. The new truck had 122 miles on it when we hitched it to the fiver and towed 250 miles across the WV mountains into PA.
I did try to take it easy but mountains are mountains. We'll see if this bites us in the butt in a few years. I will have the differential fluid changed at the first servicing. We now have 7300 miles on the truck.

Your story is familiar. I have a handful of friends who were in similar predicaments.

W5CI · 08-07-2018, 06:28 PM

You must be kidding, hook it up to you RV, whatever it is and Hammer Down. I bought several new Kenworths and always just hooked up 40,000 lbs and hit the road. same with my 2015 RAM 3500 diesel. Hammer down and don't look back

aceinspp · 08-07-2018, 06:35 PM

Ive owned a lot of new trucks over the years. Ya I tried to stay at the 500 mile mark before towing then after that I towed at what ever speed i wanted and never had an issue. Now on my new Ram I had 450 miles on it when I hitched up the tt. Drove 50 miles in hilly country and use TH and the reves where there and the speed was kept at 55. On the return trip did 62 and no TH. I do not see any issues arriving from this and I think a lot is just for the manufacture to cover there butts.

My first new car a 63 409 put over 200 miles on it the first night and laid rubber at stop lights drag racing folks all night long. Best running car I ever owned and put 70,000 miles on it when it broke a valve spring. We often believed years ago the harder you broke a vehicle in the better it would be. Can't hurt now either. What ya got a warranty for. Later RJD

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