Jump to content

Recommended Posts

Posted

Donstar-I didn't mind it really with my stock exhaust. With my new exhaust when going into V4 it sounds aweful so I want to avoid that.

 

I knew this before the purchase of the MBRP so at the moment this is my cure to that farting sound when in V4.

  • Like 1
Posted

I read what others have said but I am curious as to why you don't like your truck in V4 mode? You should only notice the change by the indicator in your DIC. Your truck has an abundant amount of power and it makes sense to reduce use when the need isn't there. I believe there is some stigma associated with running in V4 when we paid for a V8. I still feel the same way about driving a truck with an automatic transmission! If you're noticing any lack of responsiveness or power as a result of the technological advancement of AFM then your vehicle needs service, imo.

I'm with you on this one. I've often wondered why some don't like it as well. I never notice when it goes in/out of V4/V8 and if it saves some gas then all the better.

  • Like 1
Posted (edited)

A casual read thru various threads on all the GM related pickup forums should satiate your curiosity on why many folks despise the AFM thing. My basic understanding of hrydraulic lifters and how AFM does its thing and how the motor oil that is used in that function is affected was enough to convince me that I didn't care for AFM. I didn't do my homework as I should have before buying the 1500 or I wouldn't have. But it is a non issue now that I went back to a 2500.

Edited by Cowpie
Posted

I read what others have said but I am curious as to why you don't like your truck in V4 mode? You should only notice the change by the indicator in your DIC. Your truck has an abundant amount of power and it makes sense to reduce use when the need isn't there. I believe there is some stigma associated with running in V4 when we paid for a V8. I still feel the same way about driving a truck with an automatic transmission! If you're noticing any lack of responsiveness or power as a result of the technological advancement of AFM then your vehicle needs service, imo.

Some are more sensitive to their vehicles than others. Driving styles also vary. Does your 6 cylinder have afm?

 

 

Sent from my iPhone using Tapatalk

Posted

More stuff in the motor to break, 300K miles on a 5.3 without internal work not likely.

Posted

Some are more sensitive to their vehicles than others. Driving styles also vary. Does your 6 cylinder have afm?

 

 

Sent from my iPhone using Tapatalk

Yes the 4.3 has AFM. I can often predict when I may expect to see V4 light up but I can honestly say there is no feel or sound that indicates the change. My 09 Sierra had the 5.3 with AFM and it wasn't noticeable but I also didn't pay attention to it until reading concerns about AFM on this forum!

Posted

Yes the 4.3 has AFM. I can often predict when I may expect to see V4 light up but I can honestly say there is no feel or sound that indicates the change. My 09 Sierra had the 5.3 with AFM and it wasn't noticeable but I also didn't pay attention to it until reading concerns about AFM on this forum!

I can hear the difference, and feel a noticeable shudder when it switches back to 8 cylinder. Quite possibly the V6 has a smoother operation than the 8 cylinder.

 

 

Sent from my iPhone using Tapatalk

Posted

I can hear the difference, and feel a noticeable shudder when it switches back to 8 cylinder. Quite possibly the V6 has a smoother operation than the 8 cylinder.

 

 

Sent from my iPhone using Tapatalk

I have the 6.2 and honestly cannot tell when it moves in/out unless I happen to be looking at the dic.

Posted

A casual read thru various threads on all the GM related pickup forums should satiate your curiosity on why many folks despise the AFM thing. My basic understanding of hrydraulic lifters and how AFM does its thing and how the motor oil that is used in that function is affected was enough to convince me that I didn't care for AFM. I didn't do my homework as I should have before buying the 1500 or I wouldn't have. But it is a non issue now that I went back to a 2500.

 

need to bite the bullet and make the change to diesel

Posted

I have the 6.2 and honestly cannot tell when it moves in/out unless I happen to be looking at the dic.

Before my Corsa it was harder for me to tell, but I could still feel it slightly and the flapper valve would chirp. Now with the exhaust it is noticeable both with the change in exhaust tone and along the power train.

 

 

Sent from my iPhone using Tapatalk

Posted (edited)

 

need to bite the bullet and make the change to diesel

 

 

I already own enough diesels. I go thru around 20,000 gallons of diesel a year. I don't want the Dmax in my pickup. I never have had a fondness for V engines anyway, and I will not buy a V diesel, I don't care who makes it. My 2500 only racks up enough miles in a year to justify one oil change per year, and my oil change regimen is every 6000 miles or one year. A diesel under those circumstances would be stupid. My 2500 goes for weeks between startups sometimes.

Edited by Cowpie
  • 5 years later...
Posted
On 3/23/2017 at 4:03 PM, Dexter10 said:

Hey all. I am new to the forum with a 2015 Sierra 1/2 ton. I installed a cat back MBRP system and love it. Except when in V4 mode. I knew this before the install and plan on picking up a Range AFM if I can find a cheaper used one. Until then I am driving in M5 mode unless above 60mph.

 

Will this do any long term damage? I have not been shifting with the button and have let the computer shift for me if that makes sense. I start off in M5 and let it do its thing. What are people's thoughts?

 

Anyone have a used Range?

Is there a max mph I should adhere to? When in L5?

Posted (edited)
8 hours ago, Cujoxx67 said:

Is there a max mph I should adhere to? When in L5?

I’ve spent most of my life pulling heavy from half tons to one tons. They when pulling would be in the next lower gear stick or automatic once transmissions had over three speeds. Once the engines got smaller and we got more gears it seems even empty they don’t stay in high gear long anyway. The RPM dance all over at the slightest incline. My CRV with the CVT transmission spends more time at 3K RPMS at 70 than 2K. Besides possible gas mileage hit and maybe more transmission heat that test would be interesting. Maybe you should start a thread. Something like who drives in the next lowest gear? What are the effects?

Edited by KARNUT
Posted
2 hours ago, KARNUT said:

I’ve spent most of my life pulling heavy from half tons to one tons. They when pulling would be in the next lower gear stick or automatic once transmissions had over three speeds. Once the engines got smaller and we got more gears it seems even empty they don’t stay in high gear long anyway. The RPM dance all over at the slightest incline. My CRV with the CVT transmission spends more time at 3K RPMS at 70 than 2K. Besides possible gas mileage hit and maybe more transmission heat that test would be interesting. Maybe you should start a thread. Something like who drives in the next lowest gear? What are the effects?

I have been doing this for about 2 weeks now, with no obvious issues, keeping my speed below 80mph, usually 75-76mph. My rpms usually range between 2200 and 2500 sometime s bit higher, but no engine whine that I can detect. I'll do a few more weeks and update. Thanx for the feedback

Posted (edited)
9 minutes ago, Cujoxx67 said:

I have been doing this for about 2 weeks now, with no obvious issues, keeping my speed below 80mph, usually 75-76mph. My rpms usually range between 2200 and 2500 sometime s bit higher, but no engine whine that I can detect. I'll do a few more weeks and update. Thanx for the feedback

I have one car that is factory stock at 70 mph is at 4K RPMs in 5th gear it’s highest gear. It’s 22 years old.

Edited by KARNUT

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Latest Articles

  • Posts

    • Common failure.  You need to replace the fuel door housing.   The painted cover transfers over to the new housing.  To remove the old one there is 4 spots where you poke the plastic to release it.  
    • No such thing as regenerative braking on a pure ICE vehicle.     Regenerative braking is the re-capture of energy from electric motors and stores it in the battery pack.  So hybrids, PHEV and EVs have regenerative braking.     What you are seeing is the charging system changing modes is all.  Its likely entering charge mode for some sort of reason is all.  All of the charging modes will be listed below.   As for L10 vs D.  L10 turns off automatic grade braking.  L10 puts you in control of grade downshifts where in D it will automatically do it based on brake pedal position and other factors.  Otherwise L10 and D drive exactly the same aside from that one aspect.    Battery Sulfation Mode The BCM will enter this mode when the interpreted Generator output voltage is less than 13.2 V for 45 minutes. When this condition exists the BCM will enter Charge Mode for 2–3 minutes. The BCM will then determine which mode to enter depending on voltage requirements.   Charge Mode The BCM will enter Charge Mode when ever one of the following conditions are met:   Windshield wipers are ON for more than 3 s. Climate Control Voltage Boost Mode Request is true, as sensed by the HVAC control module via serial data. High speed cooling fan, rear defogger, and HVAC high speed blower operation can cause the BCM to enter the Charge Mode. The estimated battery temperature is less than 0°C (32°F). Battery State of Charge is less than 80%. Vehicle speed is greater than 145 km/h (90 mph) A current sensor malfunction exists. System voltage is determined to be below 12.56 V When any one of these conditions is met, the system will set targeted generator output voltage to a charging voltage between 13.9–15.5 V, depending on the battery state of charge and estimated battery temperature.   Fuel Economy Mode The BCM will enter Fuel Economy Mode when the estimated battery temperature is at least 0°C (32°F) but less than or equal to 80°C (176°F), the calculated battery current is less than 15 A and greater than −8 A, and the battery state-of-charge is greater than or equal to 80%. Its targeted generator output voltage is the open circuit voltage of the battery and can be between 12.5–13.1 V. When fuel economy mode is active, the generator is not charging, only maintaining open circuit battery voltage. The BCM will exit this mode and enter Charge Mode when any of the conditions described above are present.   Headlamp Mode The BCM will enter Headlamp Mode when ever the head lamps are ON (high or low beams). Voltage will be regulated between 13.9–14.5 V.   Start Up Mode When the engine is started the BCM sets a targeted generator output voltage of 14.5 V for 30 s.   Tow/Haul Mode (if applicable) Pressing the Tow/Haul Mode button located on the center stack, the vehicle system voltage is raised and the remote (non-vehicle) battery will be charged. Having the headlamps on will raise the system voltage and if the Tow/Haul button is applied it will not serve any purpose. The voltage is regulated between 13.9-14.5 V.      
    • Hello from Australia Just sharing that there is now a way to delete the active shutters entirely with just a plug in module. Opens up tons of room to light bars etc.
    • I have an observation and a question... 1) I watch the voltage closely because I have had to dial in the cut-in/cut-out voltages of the battery separator to my camper.  The "smart" charging drives me nuts.  Anyway, I noticed that when coasting for a while, and especially if lightly using the brakes (though not necessary), the voltage goes up from mid/high-13 volts to mid/high-14 volts.  Then it drops back down after stopping or going again.  Consistently!   The only explanation I can come up with is REGENERATIVE BRAKING!  Well, maybe that's a little bit of an exaggeration, but it's certainly free extra battery charging.   2) Driving on mountain roads I will use L and vary the max gear.  Things straighten out and I end up in L10.  Sometimes I leave it there for a while.  Is there any difference between L10 and D?   
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...