Break-in questions

[Atlas]

In the owner's manual for my '15 with the 5.3 it says not to exceed 55mph for the first 500 miles. That's kind of a problem given where I live. Best I can do this first week is avoid about 20 miles of interstate with meandering back-roads on my 40 mile (one-way) commute to work, and the other 20 miles are interstate. The terrain is rolling, and I try to vary the throttle pressure and my speed on the interstate (which is posted at 60, or 70 depending on the section). I also let it shift in/out of 5th and 6th when pulling grades, just to put a little pressure on the rings.

 

The engine is constantly swapping between V4 and V8 mode....I assume that's normal? (and...annoying for the other 'car guys' like me?)

 

Is there anything wrong with what I'm doing? I want to give this engine the best chance possible for a long life. But driving almost 20mph under the posted speed limit borders on dangerous/impractical and I really just wish these things would come broken in from the factory under perfect conditions.

 

 

[irish4life8911]

I would drive it like you will be driving it every day. Don't fear driving on interstate. Just don't stomp on it to 100.

I didn't break my in like you posted, I broke it in like Ive broke In all my motorcycles, no hard accelerations (full throttle) longer for 3 seconds for the first 500 miles, but at least one hard acceleration on every trip. So far, no problems from my '15

 

And v8 to v4 sounds normal. You can get a afm disabler or get a custom tune and turn it off through that if it bothers you. Mine doesn't bother me at all and can't feel it shift between the two anymore

[Rawyzf]

Where do we find the AFM disabler?

[Spurshot]

I think you're doing the right thing. Drive it nice for a while. Don't get too wrapped up in it. I would not worry about 55 mph being some magic speed. 65mph won't hurt a thing. The gearing on these trucks has the engines running at low rpm while at highway speeds. 55 mph recommended limits were in place before I had a driver's license over 40 years ago. Engines of yesteryear turned much faster due to their gearing and transmissions, yet the 55 mph recommended limit during 'break-in' has remained in place for these modern vehicles that run along at a lope. I believe 55 mph recommended limits have remained to convey a concept to new owners that they should drive 'nice' during the first few hundred miles...just in case something needs a little wear-in.

 

These engines aren't like a 1960 283. They have much more controlled manufacturing tolerances and finishes. There are no machining chips or casting sand in the engines. The metals are more compatible and oils more forgiving. Quality control is a science instead of a pain in management's backside. They aren't perfect, but man, they are good. I trust they are better than the average hot rodder's shop "blueprinting".

[Atlas]

Where do we find the AFM disabler?

 

My understanding is there is no user-configurable setting for AFM from the factory. Two options:

 

1. It can be disabled as part of a "tune", where the ECM is flashed and updated with customized programming from aftermarket tune companies. $$$

 

2. You can buy a device that plugs into the OBD port ("Range" is the manufacturer, I've heard) that disables AFM, but the device must constantly be plugged in. ~$160 is the going price if I recall.

 

I'm starting to learn the AFM algorithm, so it doesn't bother me as much when I can expect it's coming on, and I've learned to hold the throttle a little longer to keep it in V8 mode when I need it. I noticed I do have a slight squeak/chirp coming from the exhaust valve that opens/closes as part of AFM, which I hear is a common nuisance. The valve can supposedly be wired/clamped "open" to no detriment, just slightly louder/choppy exhaust in V4 mode. I'll let it do its thing for now. Chirp!

 

249 miles on the clock as of this morning. I absolutely love this truck so far. It's the most comfortable vehicle I've ever owned!

[Rawyzf]

Yeah, am trying to avoid the tune scenario as I want to keep my warranty in place for a couple years on this truck .

 

I'll look into the Range unit and see what I can find out. I have my dashboss plugged into the ODBII port now, so not having that plugged in is gonna be a bummer. Maybe there is a splitter for the ODB port so I can run both.

[MikeNH]

My 2011 is gone now but since the first time I test drove it I used M4 or M5 on lower speed roads to keep it out of the top overdrive and to keep AFM off.

[Rawyzf]

I just ordered the Range AFM Delete. It's $199 on autoanything.com, but 20% discount, so $159.20. $5.95 overnight shipping.

 

I tried to do the manual thing through low speed roads, but I felt weird shifting the truck and then wasn't sure on downshifting if there was a best practice or what not.

[MikeNH]

No you don't need to manually shift. Just leave it in M4/M5 and it will shift normally up to that gear. No 6th or 5th if you use M4 and no AFM. Much better responsiveness in town. To downshift just use the gas pedal as normal.

[Rawyzf]

So, if you're in M4 and slow down to creep around a corner for a stop sign, the truck will downshift itself to 1 or 2 and then work it's way back to 4 without you doing anything?

[MikeNH]

Yep. All you're doing is telling the trans how high a gear to use. It still up and downshifts normally.

[Silverado-Hareek]

Yep what MikeNH said. I drive like this all the time now and just click it up to M6 for extended stretches of driving at speeds greater than 45mph.

[Rawyzf]

Good info, thanks guys.

[scott19677]

So, if you're in M4 and slow down to creep around a corner for a stop sign, the truck will downshift itself to 1 or 2 and then work it's way back to 4 without you doing anything?

Tow / haul mode kicks ass also with M mode.

[tnchevy]

I wouldn't worry too much about break-in and engine life. Myself and the guys I work with get new work trucks every 3 years or so and put around 50k miles a year on them. The trucks come from the lowest bidder which is sometimes 5 or more hours away. We have always hopped right in and shot down the interstate at 80 mph and the next day be in 4low crawling up a side of a mountain and then back on the interstate doing the speed limit or more. Never had engine problems in 15 years of this. Never drained the oil early to get the "break-in" oil out and have always put in the cheapest oil and filter well past when the oil is supposed to be changed. Engines are tough these days, can't say as much about the transmission, diffs, and front suspensions, we have to get those worked on all the time around the 80k mile mark.