GM Truck Club Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
Guys and Gals. I bought a 2012 Silverado last year, crew cab 5.3 with the 6 speed auto. I am quite disappointed with it. This thing lugs when accelerating from a slow speed, hunts for gears in traffic, etc. I put it in manual mode just so it'll shift right when driving in town. To get it into passing gear on the highway I have to dick around with the gas pedal or stomp on it to shift up. No codes coming up when I take it for oil change, and the dealership says "hay we can't find anything wrong". My 1996 tahoe (only 75k miles on it) shifts so much tighter and better than this 2012. Only thing I've done to the truck is put a Volant cold air intake kit on it. It has increased overall power but anemic tranny remains. Any advice?
 

Attachments

·
Registered
Joined
·
224 Posts
If you dont like the shift points get a tune. Right now fuel econ is the main thing so that trans will keep the engine at low rpms as long as it can.
 

·
Registered
Joined
·
1,047 Posts
My 2013 feels slightly slow unless I push the pedal down. I'm used to it and it looks like GM want to keep the PRMs down as much as they can for fuel economy. I'm used to it, and I like that I'm getting combined ~19MPG.

You can get hand held tuners that you can modify shift points if you wish, just know that your fuel economy will probably suffer.
 

·
Registered
Joined
·
5,839 Posts
Guys and Gals. I bought a 2012 Silverado last year, crew cab 5.3 with the 6 speed auto. I am quite disappointed with it. This thing lugs when accelerating from a slow speed, hunts for gears in traffic, etc. I put it in manual mode just so it'll shift right when driving in town. To get it into passing gear on the highway I have to dick around with the gas pedal or stomp on it to shift up. No codes coming up when I take it for oil change, and the dealership says "hay we can't find anything wrong". My 1996 tahoe (only 75k miles on it) shifts so much tighter and better than this 2012. Only thing I've done to the truck is put a Volant cold air intake kit on it. It has increased overall power but anemic tranny remains. Any advice?
what to do is get the NON AFM engine. no one with the 1999-2006 vehicles have this issue.

I am sure you already were told by the dealership service manager that " THEY ALL DO IT ".

I know of a company that purchased a fleet of 6 cyl vehicles just because of these issues you have. prior to that they had the 5.3 L NON AFM ENGINES.
 

·
Banned
Joined
·
291 Posts
Right now fuel econ is the main thing so that trans will keep the engine at low rpms as long as it can.

I asked about the low RPM shifts and holding gears too long, I was told it was a reprogramming of the TCM because there were so many complaints regarding too much shifting in the previous versions. I asked this at the dealer I bought the truck from and the local dealer, just to verify...same answer from both. I sometimes wish mine shifted sooner than it does, but as for driveability; I have no other complaints...but its also not an AFM.

One thing to keep in mind is they aren't a car...as much as we want them to behave like a car, drive like a car, handle like a car...
 

·
Premium Member
Joined
·
6,542 Posts
Have you tried running the trans in tow mode?
Some dealerships recommend trying that vs getting a tune that may or may not void warranty.
In tow mode the trans will shift at higher rpms and has a more crisp shift.
The Hydramatic 6L80 is designed to automatically upshif if you mash the pedal and hit 5500rpms.
But like posted the main design of this trans in any application (AFM or Non AFM) is to reduce fuel consumption by keeping engine rpms low and making use of energy already spent by coasting, notice they dont do a real good job with engine braking?
The GM powertrain site can give you better specifics on the engine trans capabilitys.
http://gmpowertrain.com/VehicleEngines/PowertrainProducts.aspx
 

·
Registered
Joined
·
5 Posts
I bought Diablosport Intune for my 2012. I used it to turn off the AFM and retune the Transmission Control Module. It drives much better now, a whole lot closer to my 2005, than it did before.
 

·
Registered
Joined
·
2,378 Posts
Have you tried running the trans in tow mode?
Some dealerships recommend trying that vs getting a tune that may or may not void warranty.
In tow mode the trans will shift at higher rpms and has a more crisp shift.
The Hydramatic 6L80 is designed to automatically upshif if you mash the pedal and hit 5500rpms.
But like posted the main design of this trans in any application (AFM or Non AFM) is to reduce fuel consumption by keeping engine rpms low and making use of energy already spent by coasting, notice they dont do a real good job with engine braking?
The GM powertrain site can give you better specifics on the engine trans capabilitys.
http://gmpowertrain.com/VehicleEngines/PowertrainProducts.aspx

X2 on tow mode, I drive my '05 in tow/haul most of the time until I hit the highway. Gas mileage suffers but I don't really care, its a truck.
 

·
Registered
Joined
·
433 Posts
I purchased a SCT tuner (gm specific) http://www.sctflash.com/ and turned off the AFM. I normally drive in Tow mode and am slightly happy but a Gear Change will be the kicker for me. Yep the Tranny is the weak link to me being a happy driver of a stock gm truck.
 

·
Registered
Joined
·
555 Posts
I did the Range module thing to disable the AFM before my 2013 had 250 miles on it. Since I primarily run two lanes, gravel roads, and such with only a little in town thrown in, we pretty much use manual mode just about all the time. Only when we hit the freeway and head somewhere do we go to normal Drive. Mine does pretty good overall. Lot's of other things I find I don't like about the specs on my pickup, but the trans and rears are not on the list. The engine isn't either now that the AFM block is there and I put an oil catch can on the PCV line. Because the pricing is right, we have been using E85 ever since the first two tank fills. $2.49 (E85) vs $3.46 in my area. We averaged 17-18 mpg doing our normal two lane, gravel road thing. E85, we only dropped to 14-15 mpg, so cost per mile is cheaper using the E85. Darn good performance with that stuff also.
 
1 - 11 of 11 Posts
Top