Tuned out AFM 18 months ago... how long before lifter failure?

[NGAneer]

07 Yukon 5.3 LMG with AFM (deactivated 18 months ago), ~168k. Catch can was the first mod at 70k. Running synthetic, premium filters. Changing every 3-4k. Seafoam about once every 12 months or so. All in an effort to keep the motor clean. I'm probably forgetting a factor here so ask if you need to.

I read all the time of AFM failures, even more with higher mileage. I tuned out my AFM via BB Tune about 18 months or 40k ago. What is you opinion on how long I might go (mileage-wise) with AFM tuned out before an AFM failure?

 

[PG01]

Just from reading on here NGA, I personally believe its the luck of the draw dude.... i say keep doin wut you’re doin and if it goes, it goes. On the other hand do a mechanical delete.... if you’re that worried about it .....my opinion

 

[swathdiver]

Josh just did his and it failed, others go 200K+ miles. Take Pete's advice.

 

[08HoeCD]

There's no telling when, or if, such a failure will occur, so there's little use in fretting about it.

As others have stated, do your best and drive on.

 

[NGAneer]

10-4 guys. I'd love to delete the AFM parts now but me is broke. I'm saving my nickels until it does break or I push a head gasket or something else that requires me to crack open the motor.

 

[Infamous Ike]

I used to be an engine builder at a machine shop before I changed careers. I averaged 70-90 LSx engines a month. Whenever we sold an engine, we’d get the core back and rebuild it.

With all the experience I’ve had with Gen 3-4 LSx motor, I can agree with the previous poster that it’s all about the luck of the draw. Most of our cores were just factory units that no one modded, and lifter failures would range between 100-200k miles. Most of them were around 150-200k though. Not to scare you by any means, we had a few come through that pushed 230-240k before they tore up the cam and pushed metal through the motor.

I’ve had a few friends who have turned off AFM; a few had issues, others didn’t. Off hand, one of my buddies turned his off 40k miles ago and he currently has just under 200k on his Yukon. All stock except for a tune and he’s reported no issues so far.

I just had my Tahoe tuned and at 146k, turned off the AFM. I’m not super worried about lifter failure at this point being it had a great maintenance life prior to me taking possession, but if the thought is giving you gray hairs, I’d start saving up to pull the heads and replace the lifters/cam.

 

[randeez]

10-4 guys. I'd love to delete the AFM parts now but me is broke. I'm saving my nickels until it does break or I push a head gasket or something else that requires me to crack open the motor.

I would just ride it out, if anything keep an eye out for an entire engine to come along in the mean time cheap.
pulling the heads with that many miles i wouldnt be comfortable slapping it all back together without having the heads checked/decked, rebuilt with new guides and seals (you'd need springs if you went with a more agressive came anyway) if the heads have any warpage that means the block probably does also. new oil pump while its apart, etc etc etc.... which all equals downtime
you'd be better off slowing building another complete engine, slowly and cheaply

 

[Goodinblack]

Go ahead and build a engine in the mean time. When yours blows then you'll look forward to it.

In which case it may never blow. Hahaha

Sent from my SM-N910V using Tapatalk

 

[PG01]

Unlike you^^^^^lol

 

[09Magic]

I disabled my AFM about 20K ago on my 174,000 mile, 09 Tahoe and (knock on wood) everything seems fine. Keep in mind that AFM uses oil pressure to collapse the lifters. With the delete, your ride is not trying to collapse the AFM lifters, so it's behaving like a standard lifter. That being said, as long as there's no damage already, I'd think you can get some good miles out of your engine.