I've got a new D/A coming Monday or Tuesday. I was wondering if there is a break in period (milage) GM suggests before towing? I am leaving on a snowmobile trip on Thursday and would take the new truck if it not required to have xxxx miles on it before it tows.

I believe GM recommends 500 miles before full-throttle starts, towing or cruising at the same speed for long distances. But that's only what GM says.

Ive heard the same as well.........I believe its for the rear end more than anything.

Put a couple hundred miles on it. After that, I've always been told you break a diesel in by working it.

Break it in like you're gonna drive it. :)

I too am picking up my new D/A on Monday or Tuesday and am leaving Saturday morning on a snowmobile trip(6 hrs of trailering).


I will be towing a double trailer with 2 sleds on it. Will probably weigh around 2,000# plus the suits, boots and stuff in the truck. I am not worried about that little weight.

2 sleds and a trailer is nothing to worry about.

drive like you just stole it :lol:

Every new car, and the dmax, I have ever bought I used the same break in method.

1-200 miles up to or at or about 45. No hard acceleration.

2-400 miles up to 55 but don't hold for long. Slow but firm acceration.

4-500 miles up to 65 but don't hold for long, and accelerate up to 70 and back off every once in a while. Normal acceleration.

After 500 drive it as you normally would.

I have NEVER had a new car I broke in this way use any oil, "0" period.

I have sold these cars with over 100K on them an they all lasted to 200K, or they wrecked it and still didn't use oil.

Most people don't want to do it slow, but it has been very successful for me.

I've always broke them in as I intended to use them and I've never had any burn any oil either.

I broke mine in Plowing Snow, but it all ready had 150 miles on it from being driven from the upfitter.

My Breakin.
first 500-lots of short trips that bring everything up to temp with a full cool down after, no towing.
next 500-Same thing only towing, towed my trailer back and forth to work.
After that----Changed the rearend fluid and loaded the Predator 120 tune.