engine break in ?

[stock05hd]

whats the proper way to break the motor in.
what rpms should i stay under and for how many miles. i really want to get the most from my motor and the best gas mileage. TIA

[ChevyEvy]

I've had the same question. Problem is: there are a variety of opinions on the subject, and the owner's manual is no help here.

Some people say to baby it for XXXX number of miles, don't exceed certain speeds, rpm's, etc.

Other people say just drive it like you're gonna drive it...or even worse: drive the hell out of it. Make it settle in, I guess.

One thing I know: there is no real break in for highway tractors...you buy a new Kenworth, and you hitch it to the next load in the yard and you go.

I know that this post is no real help, but you'll probably feel the same way after reading the next ten posts :D

E

[markrinker]

I put my truck right to work, racking up most of the first 3,000 in Tow/Haul mode. I changed oil at 1,000 and plan to change again at 4,000.

The truck has never seen redline yet, in fact I try to keep it under 2,200.

My opinion? Pull anything but don't ramrod it. Ever.

[Jim Brzozowski]

stock05hd, just don't drive it any harder than you have to and especially not until everything has come up to operating temperature. I'd suggest after a couple of thousand miles to tow something heavy for a couple of hundred miles and be sure and change out the rear differential fluid after towing the first time. You really do need to work the engine a bit to get everything to seat in properly. On another post someone said somethng about a Kenworth just working it right away, I don't know about Kenworth, but I was on the Peterbuilt website a while back and they recommended you drive the tractor for 1000 miles before hooking up a trailer to it, probably not so much for the engine but to break in the gears. Once you got the engine up to operating temperature and a few thousand miles on it and changed the factory fill of oil just drive it. You won't hurt it GM sees to that by not allowing the consumer the best tune for power. They always leave some on the table for later. I don't know that anyone at this site can tell you how long one will last, they haven't been around long enough yet, but I think there was someone on here not to long ago that was approaching 400,000. I know BROKERS was claiming some big numbers, but I don't know if they were ever documented. When someone tells me they have a lot of miles, I ask for their log book. They don't lie, thats going to too much trouble. I hope I live long enough to get a million out of mine, got a long way to go, hopefully not a short time to get there.

[Heartbeat Hauler]

Originally posted by stock05hd:
whats the proper way to break the motor in.
what rpms should i stay under and for how many miles. i really want to get the most from my motor and the best gas mileage. TIA Look in your owner's manual it tells you exactly how it should be done.

I put 500 around-town miles on it first , then hitched up the 5ver and put another 1000 miles on it, then changed all the fluids & filters, oil, fuel, trans, diff and called it good.
JP