New Silverado No throttle responce, bad gas milage, clunky transmissio

[SLOW3R]

SouthernSilveradoGuy85 I have 3.42 gears.

 

How many miles are on your truck?

[Spurshot]

Jeff,

I can't add value to the discussion on the mileage, but the throttle response seems to be a programming issue. The correlation of the throttle movement to butterfly position seems to be non-linear. That is they've programmed it to be less sensitive/responsive at the first portion of the pedal movement than other GM trucks I've had. Combine that with the torque management (limiting) and it feels pretty sluggish relative to pedal position...until you get way into the pedal. This may have been done for people that tow a lot. I know it's completely a dead feeling pedal in the first part of movement compared to either of my wife's cars (2013 Ford Flex, 2001 Infinity).

 

Once you are content to with the truck and feel it's not a lemon, I recommend you get ahold of Black Bear (Justin) and talk to him about a custom tune. I thought I saw one of the programmable parameters he showed me years ago in his laptop, while plugged into my truck, included pedal/butterfly ratio.

[SLOW3R]

Thank you for the info spurshot.

 

I worry that an aftermarket tune will void the warranty. I try keep my vehicles a long time. I have a 6 year 125k bumper to bumper on this. I dont want to risk voiding it.

 

I read reviews on the aftermarket tuners and most the feedback seems like they would cure my issues. Why cant gm offer these tunes, So frustrating, how bad they killed the drive-ability of these trucks. I want to love this thing, but its imposable. If I could get my 05 back right now, I would do so in a heartbeat.

[SouthernSilveradoGuy85]

SouthernSilveradoGuy85 I have 3.42 gears.

 

How many miles are on your truck?

 

 

A little over 8,600.

[Spurshot]

Thank you for the info spurshot.

 

I worry that an aftermarket tune will void the warranty. I try keep my vehicles a long time. I have a 6 year 125k bumper to bumper on this. I dont want to risk voiding it.

 

I read reviews on the aftermarket tuners and most the feedback seems like they would cure my issues. Why cant gm offer these tunes, So frustrating, how bad they killed the drive-ability of these trucks. I want to love this thing, but its imposable. If I could get my 05 back right now, I would do so in a heartbeat.

 

 

I understand about the warranty concern. GM does this programming for a reason/reasons. I'm guessing (nobody but the GM engineers know for certain) some of it has to do with ease of use when towing or lining up trailers, some to do with protecting the driveline (trans, driveshaft, etc), and some to do with concerns over liability for various reasons. Being in company that produces a product, I expect liability isn't as big as influence as most here would expect. It's much more likely to be concerns over utility and protecting the driveline. For example, torque management that limits torque from reaching maximum levels on a time/speed scale, keeps someone from trashing the trans when towing heavy loads and mashing on it.

 

Other things like the fact that the trans holds it in a high gear for a long time as you mash the pedal slowly, further and further, then drops down to a lower gear, only to give you a burst of power/rpm. This has a basis in fuel economy. Keeping the higher gear a lower rpm boosts BMEP (brake mean efficiency pressures) and fuel efficiency. Then when the pedal is continued to be mashed further, the ECM/TCM both reach thresholds that cause it to downshift, but limit torque to keep from slamming the trans/driveline. So it all works in harmony...theoretically.

 

If you're worried about the warranty on the driveline, you might also worry about larger tires. That probably will have a play in the warranty debate if you have a driveline problem. Especially a transmission.

[SLOW3R]

Update on the mpg. I filled up this afternoon. Hand calculated this tank was 12.92 MPG. This is mixed easy driving, city/highway.

 

Even if the truck isn't "broke in" yet, this cant be right.

 

As stated before I don't drive a truck for mileage, but when my dads 3/4 ton crew cab, long bed gasser is getting better fuel economy, theres an issue.

[ccheever]

I have a 2013 4.8l silverado and I straight piped it and got a k and n and I'm getting 21 mpg but I'm looking into bigger injectors and bigger pump but would a 2013 corvette injectors fit in my truck they look about the same size

[ccheever]

It also gave me more horse power

[Ventilator]

Update on the mpg. I filled up this afternoon. Hand calculated this tank was 12.92 MPG. This is mixed easy driving, city/highway.

 

Even if the truck isn't "broke in" yet, this cant be right.

 

As stated before I don't drive a truck for mileage, but when my dads 3/4 ton crew cab, long bed gasser is getting better fuel economy, theres an issue.

I agree, there is something wrong. I have had my truck since September 2013, the worst tank MPG to date is 17 MPG. Mine averages between 21 and 22 MPG in the summer and 18 to 20 in the winter, depending on how much snow there is to play in.

 

This is all on 87 octane! GMC Double Cab,5.3L, with 3.42 gears. 15,000 on the odometer now.

[Newell33]

I have 7,600 miles on my 2014 Silverado, and it has all of the same symptoms described in this thread. I traded a 2011 Silverado with the 6.2, and every time I get into my new truck, I wish I had my old one back. I'd gladly give up the slightly better ride and slightly quieter cab for the power, smoothness, and driveability of my 6.2 without AFM. That truck was a monster, and still averaged about 18mpg down the highway. It was so nice to be able to drive it like a normal vehicle, and not have the crappy hesitation, clunks, and poor transmission shifting. And by the way, in my experience, my new truck hasn't gotten any better with more miles.

[KARNUT]

My truck runs like a shot at dog, I have to be carful not to break the tires at take off. I run E 85 and get better MPG than the op. Something is wrong with the ops truck. I don't even have the tune in at this time getting ready for service, I would take it in and bitch. Ive had a few trucks in my time I wouldn't trade for any one of them new, not even my trailblazer SS.

[GMCustomerService]

Hi Newell33,

 

 

We are truly sorry to hear you feel this way about your new Silverado. I can certainly understand how you feel and we want you to be happy with your vehicle. Has your dealership made any attempts to resolve your concerns? I'm happy to discuss your concerns further. Please send me a private message with your VIN and contact information.

 

Andraya

GM Customer Care

[SLOW3R]

Hi Newell33,

 

 

We are truly sorry to hear you feel this way about your new Silverado. I can certainly understand how you feel and we want you to be happy with your vehicle. Has your dealership made any attempts to resolve your concerns? I'm happy to discuss your concerns further. Please send me a private message with your VIN and contact information.

 

Andraya

GM Customer Care

 

 

 

 

Thanks for reaching out to me, beings im the one that started this post...........

[OmniGLH]

 

 

I understand about the warranty concern. GM does this programming for a reason/reasons. I'm guessing (nobody but the GM engineers know for certain) some of it has to do with ease of use when towing or lining up trailers, some to do with protecting the driveline (trans, driveshaft, etc), and some to do with concerns over liability for various reasons.

 

That's probably some of it. I used to work for an engine manufacturer as a software engineer, we sold our engines to another large auto manufacturer for use in their 3/4 and 1-ton pickups. We had to program in a really dead-feeling pedal too, specifically because one day, a senior engineer at the truck mfr (who happened to be a relatively short, petite female) took one of the mules for a drive. She hopped in, stuck it in drive, hit the gas - and the truck LEAPED forward. The sudden movement of the truck caused her to slide back in her seat, and when that happened, her foot came off the pedal. She wiggled herself forward in the seat again, hit the pedal, truck leaped, she slid back. She did this dance 4-5 times before stopping, putting it back in park, and proclaiming the gas pedal was too touchy.

[KMGZ400]

Maybe he has the 3.08 and dosent know it? Do you have the build sheet OP?