darn afm, i wanna kick it in the teeth

[joshw1303]

I like the afm, its just GM its new to this technology. I drove a hemi and it was seamless, wish GM could've like that.

[uchi]

i wish mine stayed seamless. the thing is the afm isnt new tech, its been around for like 30 or 40 years, i think chrystler was one of the first to use it.

[MikeNH]

Have it completely disabled....you won't see a bit of loss in mileage and you won't start consuming oil either.

 

 

 

Wrong. People without AFM or with it disabled have had oil consumption issues as well.

 

 

OP- when in town use manual mode and keep the trans in M4 or M5. I've done this since day one and you get much better throtle response as the trans isn't lugging around in too high a gear. Almost everything is like this now, the trans is programmed to reach a high gear ASAP in the name of fuel economy.

[VT_Z71]

What we need is a FACTORY ORDER and a software program to turn the AFM off at the Dealer at the owners request. My concern with an aftermarket tune is apparantly the computer does record a "change event". You can turn the tune off before taking it to the dealer but if they dig deep enough they will know the truck was modified.

 

 

Buy some used computer modules for your truck. Tune those the way you want (including completely turning off AFM). Install and use the tuned modules on a daily basis, and simply swap in your stock ones whenever a trip to the dealer is necessary. Swap process takes all of 5 minutes (4 of which include gathering a socket set and disconnecting battery). There should be no trace of you tuning anything away from GM specs.

 

From everything I understand, the only vehicles that GM can completely track as far as 'change events' at this time are the newer Duramaxes.

[Morgan1986]

I like the afm, its just GM its new to this technology. I drove a hemi and it was seamless, wish GM could've like that.

 

dad has a hemi he likes the afm thing alot. He has never complained about it .

[SouthCo]

With the stock exhaust, I never noticed any difference between v4 or v8 with the afm. Since I put the Corsa Sport exhaust on, I do notice a different exhaust tone when I have slight pressure on the gas pedal when cruising and it's about to go from v4 to v8. Otherwise it's still pretty seamless. I'd prefer not to have it but for now it'll stay. My brother-in-law has a 2007 tahoe with 5.3 afm and he hasn't had any issues. So gm has been using these for going on 5 years that I know of. You'd think that would be long enough to have them perfected if in fact afm is causing some oil issues. But like another poster said, even some non-afm engines have oil issues. Again, I'm not tuning mine out yet, but would rather not have it even though it hasn't caused me any problems (knock on wood).

[NoMoreGM4Me]

Have it completely disabled....you won't see a bit of loss in mileage and you won't start consuming oil either.

 

 

 

Wrong. People without AFM or with it disabled have had oil consumption issues as well.

 

 

OP- when in town use manual mode and keep the trans in M4 or M5. I've done this since day one and you get much better throtle response as the trans isn't lugging around in too high a gear. Almost everything is like this now, the trans is programmed to reach a high gear ASAP in the name of fuel economy.

 

 

Well, my truck consumed oil on the stock tune and it didn't use a drop with the AFM turned off in my custom tune. I even went back to the stock tune for a couple of months and it once again started using oil....put the tune back in and not a drop!

 

Draw your own conclusion.

 

Also, if I am wrong, then why does GM have a TSB out for oil consumption in AFM engines to install an oil deflector to prevent oil mist from a valve from entering the combustion chamber?

 

Maybe you ought to inform GM that AFM is not the cause of oil consumption so they can stop wasting all that money fixing this problem that is not the cause.

[09Jimmy]

My truck with a 5.3 AFM burned oil from day one. When I started it in the morning a cloud of smoke would pour out the back and my Ford and Dodge owning neighbors would laugh at my brand new POS GM. The dealer did three oil consumption tests and finally replaced all the lifters and valve cover. It didn't help one bit, I still burned a quart of Mobil 1 every 600-800 miles.

I hated my tuck so much I tried to blow it up so I could just put a 6 or 6.2 liter in it. I took it on a 1000 mile trip through the Rockies and back, most of the time holding it in each gear until it bounced off the rev limiter for 10-15 seconds. I drove it at the top speed limiter for 10 miles at a time and that sucker wouldn't even go above operating temperature, let alone blow up.

I parked it and didn't drive it for 2 months, cursing it every day because I was ashamed to drive a smoker. Well, winter came and I couldn't drive my summer cars anymore so I had to drive the truck. On a whim, I drove it down to Wester's Garage and had Lyndon do a high octane tune on it and turn off the AFM.

Whithin 2 days it stopped burning oil and hasn't burned a drop since. So yes, I believe AFM is the culprit of the oil burning 5.3s. Now I love my truck again and it has blown the doors off my neighbor's trucks with the new tune.

[Quint]

I am at 20,400 miles odometer reading. With factory tune (nannies and all) and stock exhaust, I cannot hear or feel one bit of anything when the truck cycles between v8 and v4 modes. I have to rely on the DIC to know what mode it's in. I have tried and tried to notice any difference when watching the DIC display change from one mode to another, and to me it's completely seamless. Through observation I can glean exactly what conditions must be met for it to change mode, but I can't feel anything when it does.

 

I change oil every 5,000 miles and check the dipstick once a week. The level on the dipstick has seemingly never changed the whole time I've owned the truck. However when I change the oil and put the used oil back in the 5-quart bottle, the level on the bottle's 'sight glass' shows there's only 4.5 quarts of used oil in it. Since I doubt there's a whole half quart clinging to the drain pan, I figure I'm burning just a little bit off per 5k interval.

[RyanbabZ71]

I hated my tuck so much I tried to blow it up

 

So you tried to gernade your engine and it held up? Sounds like the 5.3 AFM engine is awful, great story illustrating that even with some issues it is a strong motor.

[NoMoreGM4Me]

I am at 20,400 miles odometer reading. With factory tune (nannies and all) and stock exhaust, I cannot hear or feel one bit of anything when the truck cycles between v8 and v4 modes. I have to rely on the DIC to know what mode it's in. I have tried and tried to notice any difference when watching the DIC display change from one mode to another, and to me it's completely seamless. Through observation I can glean exactly what conditions must be met for it to change mode, but I can't feel anything when it does.

 

I change oil every 5,000 miles and check the dipstick once a week. The level on the dipstick has seemingly never changed the whole time I've owned the truck. However when I change the oil and put the used oil back in the 5-quart bottle, the level on the bottle's 'sight glass' shows there's only 4.5 quarts of used oil in it. Since I doubt there's a whole half quart clinging to the drain pan, I figure I'm burning just a little bit off per 5k interval.

 

 

Your engine requires 6 qts, not 5.

[Quint]

Your engine requires 6 qts, not 5.

 

Incorrect.

[RyanbabZ71]

Your engine requires 6 qts, not 5.

 

Incorrect.

 

 

[NoMoreGM4Me]

Your engine requires 6 qts, not 5.

 

Incorrect.

 

 

I suggest you read your owners manual.

[Quint]

2008 Silverado owner's manual, page 5-133, Capacities and Specifications:

 

Engine oil with filter, 4.8L V8; 5.3L V8; 6.0L V8 | 5.0 qt

 

Looking right at it.