Rattle/grinding noise at 25-35 mph, mechanic told me AFM and lifters need to be changed.

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iboughtatahoe23

iboughtatahoe23

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And I wish I could just not drive it but it’s my only car and my job is 3 miles away from my place.
 

Trey Hardy

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2014 Tahoe 167k miles.

I’ve posted one thread about this recently that seems to have gone dead. So I’m making a new one.

Noise I’m having will usually happen from 25-35, mph when i accelerate around those speeds lightly. It seems to only happen in v4 mode and then when it “jerks” into v8 mode the rattle goes away. It’s a very audible rattle/scrape like dragging solid metal behind you. People look at me when driving down Main Street.

8/15/23:
Went to the shop again and took a ride. The mechanic told me i most likely will need lifters changed and it’s gonna run about $2500 or more.

On the other hand: My dad told me I should run 15w40 Rotella and I should be able to get another 150 K out of it but I think he’s blowing smoke just a little bit haha.


Wht you guys think? I’m kind of nervous to just take out a loan and throw money at some thing. But I’m pretty sure if it only happens when switching out of v4 and going into full V8 then I’m almost 90% sure it’s AFM related.
I have prolonged my afm lifters by swapping to 10w40 Mobil one with a quart or marvel mystery oil
Along with disabling my flex fuel with a custom tune but you can also get a afm disabler that plugs into your obd2

I had a lifter stick on me twice now and both times I got it broke loose with the marvel mystery oil and driving it like I stole it. Try this at your own Risk but I’m almost 2 years into it with no issues what so ever
Just step up a weight in oil as the mmo thins the oil
 

the 18th letter

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And I wish I could just not drive it but it’s my only car and my job is 3 miles away from my place.
I'd probobly never drive to work if I lived 3 miles from my job. Everyone's situation is different which I can respect. Buy the lower cost disabler and start trying to get a repair savings fund going.
 

NickTransmissions

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I’m a bit confused because a lot of people recommend the plug in Disablers and they work fine they say.


But if my problem is worse , like an already failed lifter I could see why it wouldn’t work really. It might stop my noise and stop further damage?

Or I can do that Texas speed AFM delete kit or WhatVer with the new lifters
In many cases, web-based diagnosis from well-meaning members will only get you so far and eventually it comes to a point where you need a full, hands-on diagnostic work up from a competent shop/service center who will spell out the problems as well as cost to cure in writing.

You can try any of the suggestions above however I'll echo @wjburken and recommend you obtain a complete diagnosis so you can determine what it's going to cost to fix. This way, you can take next steps with financing and logistical arrangements confident you have a complete, accurate picture of the situation and fix it once and for all the right way.

I'd rather deal with a potential $2500-$3000 problem now, install a full and proper AFM/DOD delete kit (new cam, lifters, OEM lifter trays) from whomever (TSP for example) and anything else needed (maybe even scope in an oil pump/pump pick-up O-ring and exhaust manifold leak repair as part of the service) vs spending $6000-$8000+ later on a full engine rebuild/replacement because one or more of your lifters completely failed, little lifter roller's needle bearings sent through the engine like shrapnel tearing up your main/rod/cam bearings, destroying your cam and turning the thing into 600 lbs or so of scrap metal, oil and aluminum.

My .02
 
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iboughtatahoe23

iboughtatahoe23

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I have prolonged my afm lifters by swapping to 10w40 Mobil one with a quart or marvel mystery oil
Along with disabling my flex fuel with a custom tune but you can also get a afm disabler that plugs into your obd2

I had a lifter stick on me twice now and both times I got it broke loose with the marvel mystery oil and driving it like I stole it. Try this at your own Risk but I’m almost 2 years into it with no issues what so ever
Just step up a weight in oil as the mmo thins the oil
What year?
 
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iboughtatahoe23

iboughtatahoe23

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I'd probobly never drive to work if I lived 3 miles from my job. Everyone's situation is different which I can respect. Buy the lower cost disabler and start trying to get a repair savings fund going.
Ok, does anyone know if it’s ok to drive In M5 in Manuel?
 

lightflyer1

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You can drive in M but economy will drop some. The disabler isn't a fix all. It just stops the lifters from opening and closing all the time and keeps them locked all the time. If there is damage there is damage and wear will continue until it quits or fixed. I bought mine with a tick at a discount and repaired it back to stock with new parts. Then added the diabler to keep it in V8 mode all the time. Still no guarantee from my reading but the chances seem to be less. It is an extra vehicle for me so should last its/my lifetime hopefully. Mine had a bent pushrod on the intake of number 4 cylinder.
 
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iboughtatahoe23

iboughtatahoe23

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You can drive in M but economy will drop some. The disabler isn't a fix all. It just stops the lifters from opening and closing all the time and keeps them locked all the time. If there is damage there is damage and wear will continue until it quits or fixed. I bought mine with a tick at a discount and repaired it back to stock with new parts. Then added the diabler to keep it in V8 mode all the time. Still no guarantee from my reading but the chances seem to be less. It is an extra vehicle for me so should last its/my lifetime hopefully. Mine had a bent pushrod on the intake of number 4 cylinder.
Can I pop the valve cover off and see what’s wrong?
 
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iboughtatahoe23

iboughtatahoe23

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In many cases, web-based diagnosis from well-meaning members will only get you so far and eventually it comes to a point where you need a full, hands-on diagnostic work up from a competent shop/service center who will spell out the problems as well as cost to cure in writing.

You can try any of the suggestions above however I'll echo @wjburken and recommend you obtain a complete diagnosis so you can determine what it's going to cost to fix. This way, you can take next steps with financing and logistical arrangements confident you have a complete, accurate picture of the situation and fix it once and for all the right way.

I'd rather deal with a potential $2500-$3000 problem now, install a full and proper AFM/DOD delete kit (new cam, lifters, OEM lifter trays) from whomever (TSP for example) and anything else needed (maybe even scope in an oil pump/pump pick-up O-ring and exhaust manifold leak repair as part of the service) vs spending $6000-$8000+ later on a full engine rebuild/replacement because one or more of your lifters completely failed, little lifter roller's needle bearings sent through the engine like shrapnel tearing up your main/rod/cam bearings, destroying your cam and turning the thing into 600 lbs or so of scrap metal, oil and aluminum.

My .02
Ugh… it sucks! Just got this tbinfs in February
 
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iboughtatahoe23

iboughtatahoe23

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So spend the money on a diagnosis from a Chevy delaer? Or go local. Seems local shops can never find the issue. Took 4 trips for them to find a noise
 

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