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Afm/ Computer Issues

phxballer50

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phxballer50 New Member

phxballer50

Posted
Posted

I am new to the forum but have enjoyed ready about all of your trucks.

 

I bought a new 08 chevy silverado LT supercrew with 5.3l with AFM. I have always owned chevy but this truck and the dealer are about to push me to go buy a ford. I am going to try and explain the problem and maybe you guys will be able to help me explain it to the idiots at the dealership that keep telling me it is normal in chevy trucks.

When I pull up to red lights and come to a complete stop, the transmision will engage and slam the truck forward feeling like I have been rearended. This happened twice while the tech was driving my truck and he still swears it is not a problem. The service manager told me it is an issue that chevy is aware of and it is in the computer and has to do with timing but does not have a fix for it currently. The problem has gotten progressively worse and now I am worried that other parts are wearing and I will get stuck with a 36k piece of crap.

 

My fathers 2500 does not do this and neither does any of my buddies trucks. I am the only one that has the AFm and wonder if that has something to do with this. Maybe a tune turing it off will hel

VMax2007 Senior Enthusiast

VMax2007

Posted
Posted
I am new to the forum but have enjoyed ready about all of your trucks.

 

I bought a new 08 chevy silverado LT supercrew with 5.3l with AFM. I have always owned chevy but this truck and the dealer are about to push me to go buy a ford. I am going to try and explain the problem and maybe you guys will be able to help me explain it to the idiots at the dealership that keep telling me it is normal in chevy trucks.

When I pull up to red lights and come to a complete stop, the transmision will engage and slam the truck forward feeling like I have been rearended. This happened twice while the tech was driving my truck and he still swears it is not a problem. The service manager told me it is an issue that chevy is aware of and it is in the computer and has to do with timing but does not have a fix for it currently. The problem has gotten progressively worse and now I am worried that other parts are wearing and I will get stuck with a 36k piece of crap.

 

My fathers 2500 does not do this and neither does any of my buddies trucks. I am the only one that has the AFm and wonder if that has something to do with this. Maybe a tune turing it off will hel

 

GM doesn't make a "supercrew", that's a Ford. Interesting how someone who has "always owned chevy" would make that mistake. :thumbs:

 

And FYI, this is common and certainly nothing to worry about and it has nothing to do with AFM.

tobias Senior Enthusiast

tobias

Posted
Posted

You have a 5yr, 100K mile drive train warranty. Even if it takes a while to come up with a "fix", you'll be covered. Make sure you have proof that you've brought this issue to their attention and keep track of your visits and you should be fine.

phxballer50 New Member

phxballer50

Posted
  • Author
Posted
I am new to the forum but have enjoyed ready about all of your trucks.

 

I bought a new 08 chevy silverado LT supercrew with 5.3l with AFM. I have always owned chevy but this truck and the dealer are about to push me to go buy a ford. I am going to try and explain the problem and maybe you guys will be able to help me explain it to the idiots at the dealership that keep telling me it is normal in chevy trucks.

When I pull up to red lights and come to a complete stop, the transmision will engage and slam the truck forward feeling like I have been rearended. This happened twice while the tech was driving my truck and he still swears it is not a problem. The service manager told me it is an issue that chevy is aware of and it is in the computer and has to do with timing but does not have a fix for it currently. The problem has gotten progressively worse and now I am worried that other parts are wearing and I will get stuck with a 36k piece of crap.

 

My fathers 2500 does not do this and neither does any of my buddies trucks. I am the only one that has the AFm and wonder if that has something to do with this. Maybe a tune turing it off will hel

 

 

Your right, I meant to say crew cab.

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VMax2007 Senior Enthusiast

VMax2007

Posted
Posted

BTW, mine does this too, always has. Doesn't bother me anymore. I also had my AFM turned off (for other reasons) and it had no effect. I believe it's in the tranny, but one theory is the slip yoke.

rvsahs Senior Enthusiast

rvsahs

Posted
Posted
BTW, mine does this too, always has. Doesn't bother me anymore. I also had my AFM turned off (for other reasons) and it had no effect. I believe it's in the tranny, but one theory is the slip yoke.

:thumbs: And welcome to GMT!

brims Senior Enthusiast

brims

Posted
Posted

Like others, I have had this same issue, I too thought I got rearended a couple of times. If it breaks something, I'll be pissed, but if nothing happens, then I'm fine with it.

MS3DALE Senior Enthusiast

MS3DALE

Posted
Posted
but one theory is the slip yoke.

 

It is,Theres a bulletin on it on lubing the slip yoke splines.

 

Welcome aboard!!!

Z71kris Senior Enthusiast

Z71kris

Posted
Posted

We started noticing this in our TB, it has happened twice now, but its only the v6, and it (obviously) does not have afm.

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