Afm Lifter Replacement Results

rckt442 · January 16, 2009

I went to the dealer today to pick up my truck after having all 16 lifters replaced. And by the way, for those that were questioning whether or not the heads have to be pullled - they do.

So I sign the papers, get my keys, start it up (no apparent lifter noise), and then start to drive home. 10 miles later a very loud knocking noise starts, coming from the top of the motor that sounds to me like a lifter completely collapsed or a rocker arm pulled loose. I pull over to the side of the road and call the dealer, get towed back and another rental car. I was pretty pissed off, but bit my tongue and was very polite with the service writer and the technician since now its on their dime (and not GM's unless its a faulty part) and I don't want them to cut corners. They will be pulling it back apart tomorrow to see whats going on. I'm hoping whatever it is, it didn't damage anything else (e.g.the camshaft). So basically, I don't really know if replacing the lifters fixed the issue, since the truck was still warm from the mechanic's test drive by the time I got there.

They told me that this was the second Vmax that they had replaced lifters on and they did use the TSB on the AFM lifter issue. The other truck that had the lifters replaced was done by the same tech and it did not have any issues with the repair (or so they tell me).

Wish me luck, guys. The truck only has 8,000 miles on it and is mainly used for towing my 6500 lb travel trailer.

jrrod2004 · January 16, 2009

I went to the dealer today to pick up my truck after having all 16 lifters replaced. And by the way, for those that were questioning whether or not the heads have to be pullled - they do.

So I sign the papers, get my keys, start it up (no apparent lifter noise), and then start to drive home. 10 miles later a very loud knocking noise starts, coming from the top of the motor that sounds to me like a lifter completely collapsed or a rocker arm pulled loose. I pull over to the side of the road and call the dealer, get towed back and another rental car. I was pretty pissed off, but bit my tongue and was very polite with the service writer and the technician since now its on their dime (and not GM's unless its a faulty part) and I don't want them to cut corners. They will be pulling it back apart tomorrow to see whats going on. I'm hoping whatever it is, it didn't damage anything else (e.g.the camshaft). So basically, I don't really know if replacing the lifters fixed the issue, since the truck was still warm from the mechanic's test drive by the time I got there.

They told me that this was the second Vmax that they had replaced lifters on and they did use the TSB on the AFM lifter issue. The other truck that had the lifters replaced was done by the same tech and it did not have any issues with the repair (or so they tell me).

Wish me luck, guys. The truck only has 8,000 miles on it and is mainly used for towing my 6500 lb travel trailer.

fawk, that seriously sucks

mattgob86 · January 16, 2009

That sounds truly awesome.......NOT, . I wish you luck. My dads 08 tahoe has 20000 miles on it and had the fuel pump go out and was at the dealer for like 4 weeks because GM was either reworking the pumps or hadn't issued replacements. I sure hope these type of things aren't widespread or there will be some really pissed of GM owners

Spurshot · January 16, 2009

Really a pisser, Todd. Sorry to hear that.

Matt, an 08 Tahoe has a GM fuel pump that is used in millions of other vehicles. Someone isn't telling it telling your dad like it really was.

mattgob86 · January 16, 2009

yea well he has had it back for a couple months and it runs fine and but when it was starting to go out it started hard and on the GMT900, the starter just takes over until the engine starts and it would just crank and crank so we would just go through that a couple times and it would start. He would be driving around and all of a sudden the trac control would say it is off w/o touching the button and then it would come back on, that continued plus the stabilitrak would do the same. Brought it to the dealer and they said that the fuel pump is on the same relay as the stabilitrak and trac control and that is the vehicles way of saying that the fuel pump is dying. So it was at the dealer for a couple weeks and he got tired of waiting because they said that they did not have a pump on hand because GM was reengineering it so he took it and just delt with it till the pump came in. Sorry for jacking your thread Todd,

mr_bots · January 16, 2009

That really sucks. Hopefully no serious damage was done and they get it back to you in mint condition.

mattgob86 · January 16, 2009

yea its running like a champ now but i think my dad has a lead foot because the fuel mileage has never been what it shoud be but o well

J-man67 · January 16, 2009

That sucks man, hope it works out for you. I had mine in for the lifter ticking. Long story short, they couldn't replicate it over 3 days. I get there to pick it up and it does it. I show them, they hear it, then tell me they can't replace b/c the bulletin tells them not too as GM is redesigning them. I am calling other dealerships as I type this. I am fuggin LIVID!

That really sucks. Hopefully no serious damage was done and they get it back to you in mint condition.

yea its running like a champ now but i think my dad has a lead foot because the fuel mileage has never been what it shoud be but o well

HA, I am pretty sure he was saying that to the original poster of this thread....

BuckFeverZ · January 16, 2009

That truly sucks. My truck was in the shop for just about two weeks about a year ago because the CEL light came on and the AFM was not kicking on. They figured it was something internal in the motor, and they tore it all apart. After replacing numerous parts, the problem still wasn't fixed. So, on a whim, they replaced the ECM and bingo! No more CEL light

bubba33 · January 16, 2009

That truly sucks. My truck was in the shop for just about two weeks about a year ago because the CEL light came on and the AFM was not kicking on. They figured it was something internal in the motor, and they tore it all apart. After replacing numerous parts, the problem still wasn't fixed. So, on a whim, they replaced the ECM and bingo! No more CEL light

They tore apart the motor for a electrical problem. I would not go back there and let them work on my truck.

BuckFeverZ · January 16, 2009

The code it was giving was something related to the AFM. Neither they nor GM, could figure out what was causing the code. GM were the ones that told them to tear into the motor and replace parts, it wasn't the dealers idea. The dealer was the one who eventually fixed the problem with the new ECM, not GM.

rckt442 · January 16, 2009

Update - they pulled the driver's side valve cover and used a boroscope to get a look at each lifter. They found one that had come apart at the top. So basically its a bad part and they will be getting a new lifter and all of the gaskets to pull the intake and head again. Although its still not good, at least they will be getting paid by GM to fix it (read as "no shortcuts"). It could have been worse.

After all of this, I really hope that the original problem is fixed. I'm still a bit skeptical about the lifters being the source of the clattering noise.