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Posted
On 2019-07-11 at 10:57 AM, the33z33 said:

That's actually not terrible for being lifted on 35s. I hang around 18.2 lowered on 30s with the factory 3.08 gears 6 speed.

 

My range disabler comes in today. Can't wait to finally use my 6th gear and stop driving around in M5 all the time lol.

Really? My 6.2L sits at 12.8L/100km on 33x12.5 10ply's and I thought that was pretty bad. My CCLB 6.0L does 20L/100. No range, but my 6.2L rarely goes into V4 unless in town. I figured lowering would improve mileage. 

 

I was hoping Trumpy in the US would slap the shit out of the EPA a little bit on these ridiculous economy demands, but he hasn't done that yet. Now GM's focus is autonomous electrics. Scary stuff. Until then we are going to get sketchy technologies like the diesel EGR and DEF, the unreliable and rough AFM and Start/Stop insanity, that save about $10 in gas per year but costs you $10,000 when it fails. 

 

OP let us know the invoice value when all the work gets done. 

Posted (edited)

My truck is at 19,500km. Its a 2017 sierra 1500, 5.3. As you can tell from the low mileage, I'm a city driver.

 

I put in a range AFM disabler about two weeks ago to hopefully avoid this issue. I guess I'll never really truly know if my lifters would have failed if I hadn't blocked AFM, but I figure the odds are in my favor.

 

In the city, I've seen less than a 0.5mpg decrease in gas mileage.

 

One thing I have noticed is that it drives WAY better with no AFM. The transmission no longer does that schizophrenic, confused, back and forth thing it used to do, especially in large parking lots or suburban lane ways. No more hesitation when accelerating before a lane change too. The truck feels more responsive, and therefore safer.

 

There isn't much difference in the highway. I never noticed AFM there much anyway.

 

I plan to tune out AFM completely when my power-train warranty is up.  If I ever experience a lifter failure, I'll consider a mechanical AFM delete. Everything I've read is that software AFM delete (either range or tune) is as good as it gets for preventing lifter failure ahead of time. Mechanical delete is only worth the expense if you plan to take the engine apart anyway (like if your lifters and cam have already failed).

Edited by Baytrucker
  • 2 weeks later...
Posted

After 3 weeks of my truck sitting at the dealership waiting on parts they have now told me it was just a couple broken bolts on the exhaust manifold. After replacing the sounds have gone away. Seems to be a different story every time I speak to the service advisor. Picking the truck up tomorrow so I will see for myself in the coming weeks.

 

I like the idea of trying out the Range AFM disabler to prevent this type of issue from happening in the future. More responsive sounds good to me as I often experience the hesitation Baytrucker has mentioned.

 

 

 

 

Posted
7 hours ago, Melks said:

After 3 weeks of my truck sitting at the dealership waiting on parts they have now told me it was just a couple broken bolts on the exhaust manifold. After replacing the sounds have gone away. Seems to be a different story every time I speak to the service advisor. Picking the truck up tomorrow so I will see for myself in the coming weeks.

 

I like the idea of trying out the Range AFM disabler to prevent this type of issue from happening in the future. More responsive sounds good to me as I often experience the hesitation Baytrucker has mentioned.

 

 

 

 

That sounds awful fishy to me. Make sure you keep an eye on it before your warranty is up.

Posted
On ‎7‎/‎10‎/‎2019 at 11:35 AM, Kylebr1 said:

I have 105,000 km now with AFM turned off and have had zero issues . 

160,000 kilometers on mine with the AFM active. Have has zero issues. 

7.25 liters / 100 km lifetime metered average. 

 

I expect it to puke any day now. 

?

 

?

Posted
25 minutes ago, Grumpy Bear said:

160,000 kilometers on mine with the AFM active. Have has zero issues. 

7.25 liters / 100 km lifetime metered average. 

 

I expect it to puke any day now. 

?

 

?

On the V6 how many lifters are AFM? Just curious

Posted

Just an update - after 3 weeks of my truck sitting at the dealership waiting on parts (cam shaft, lifters, intake manifold) they finally began working on my truck and noticed broken exhaust manifold bolts. They replaced 5 bolts in total and the sound has gone away. No new parts were needed or used and the motor was not taken apart. False diagnosis.?

  • 11 months later...
Posted

Just got news that my 2019 Z71 Trail Boss needs Cam Lifters and a spark plug was fouled. so I'm not sure how this is going to work out. I contacted Chevrolet 1-800 today to start a case this truck has 35,500 miles. Anyone else has this happen to? This is still a new truck I take care of it really well.

  • 8 months later...
Posted
On 7/16/2019 at 2:15 PM, Baytrucker said:

My truck is at 19,500km. Its a 2017 sierra 1500, 5.3. As you can tell from the low mileage, I'm a city driver.

 

I put in a range AFM disabler about two weeks ago to hopefully avoid this issue. I guess I'll never really truly know if my lifters would have failed if I hadn't blocked AFM, but I figure the odds are in my favor.

 

In the city, I've seen less than a 0.5mpg decrease in gas mileage.

 

One thing I have noticed is that it drives WAY better with no AFM. The transmission no longer does that schizophrenic, confused, back and forth thing it used to do, especially in large parking lots or suburban lane ways. No more hesitation when accelerating before a lane change too. The truck feels more responsive, and therefore safer.

 

There isn't much difference in the highway. I never noticed AFM there much anyway.

 

I plan to tune out AFM completely when my power-train warranty is up.  If I ever experience a lifter failure, I'll consider a mechanical AFM delete. Everything I've read is that software AFM delete (either range or tune) is as good as it gets for preventing lifter failure ahead of time. Mechanical delete is only worth the expense if you plan to take the engine apart anyway (like if your lifters and cam have already failed).

I have been using the Range AFM disabler for about 2 years now.  It did not prevent the lifters from failing.  My truck is being torn apart at the dealership right now. 

Posted
On 7/29/2019 at 6:15 AM, Gagliano7 said:

On the V6 how many lifters are AFM? Just curious

Two cylinders. 

 

Sorry just saw this. 

Posted
20 hours ago, JC021 said:

I have been using the Range AFM disabler for about 2 years now.  It did not prevent the lifters from failing.  My truck is being torn apart at the dealership right now. 

Were they AFM lifters or non-AFM lifters? Both types fail. Just fail differently 

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