Engine Break-In

[Porkchopexpress]

I have the Cummins and I see according to the owners manual there is no break-in period (glad I don't have a gasoline engine, 300 miles at 50-55 would be hard to do), so my question is more with the towing. One section says no break-in for the cummings but the other says no towing for 500 miles due to the drive train. Then it says when towing a trailer for 500 miles do not drive over 50 MPH. 50 MPH is the minimum speed on the turnpikes around me. I will be pulling a Grand Design Reflection 5th wheel. How important is this 500 miles "break-in while towing"

 

[RV_Goose]

I only have a 12K toyhauler. But I quickly put 500 miles on the truck for breakin. When I towed down to Florida I ran varying speeds from 55-70. Used all aspects of the truck (engine braking, pedal beaking, trailer brakes (just to test that the module worked well)). After 1100 miles I then hitched up an equipment trailer that weighed in about 22K. Truck never missed a step.

I have a 2020 RAM 3500 CC LB Dually HO Aisin. I probably would not tow near max for 1000 miles. But after 500, most RVs are not going to max out a dually 3500. A SRW truck can be close to max RAWR with a 5th wheel RV.

 

[Southernspeed]

Although the engine doesn't need breaking in, the ring and pinion gears will need bedding in and I expect the trans clutches too. My 'hay hauling season' started a couple of weeks after I got my 3500 dually so I put a little over 700 miles on it then towed at 50 mph as suggested and just let people get frustrated behind me! Not shortening the life of my truck to suit them lol.

 

[jetrinka]

Although the engine doesn't need breaking in, the ring and pinion gears will need bedding in and I expect the trans clutches too. My 'hay hauling season' started a couple of weeks after I got my 3500 dually so I put a little over 700 miles on it then towed at 50 mph as suggested and just let people get frustrated behind me! Not shortening the life of my truck to suit them lol.

^^^This. The ring and pinion need time and a few good heat cycles to break in properly before being really used hard.

 

[Firebird]

Ran 600 miles at first, then hitched up the camper and started hauling

 

[John Jensen]

^^^^^ Same as Firebird

 

[sstoner911]

In 30 years I have never waited 500 miles to break in The ring and pinion.

Hell, with 11 miles on the clock went 1500 miles first trip towing.

 

[PatriotHD]

Had 200 miles on mine with I hooked up the boat and pulled the 700 mile trip to FLA.

 

[jleonard]

I thought I had 501 miles on mine when I first towed my 6500 lb TT, but after I started, I realized I was mistaken. I only had 380 miles.
Please don't tell anyone of my mistake.