2009 Tahoe - Need help with AFM/DOD full delete parts list.

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Just Fishing

Can't fix stupid
Joined
Aug 30, 2020
Posts
3,842
Reaction score
8,275
Location
Utah
Recently i had a sudden drop of oil pressure on my 09 tahoe...
while it's still in spec, and i have DOD disabled via tune, it's still nagging at me.
looks like i'm holding a steady 25-28psi at hot idle...

Main thing i don't like is following the 10psi per 1k RPM, when i get up in the 5k range, the oil pressure seems a tad too low.

Some background,
I had been running nice clean M1 5w30, and i had some seafoam in the oil before the oil change before that in order to resolve some lifter tick i heard.
(Later i learned about DOD/AFM)

Well, i had the truck on jackstands for a good solid week, front of the truck in the air in order to rebuild the valve body with a shift kit and new transgo valves, and a proactive pressure switch rebuild.

Starting her back up, i applied the stock program (and forgot to re-disable AFM).
Let it heat up, and i ran the transmission adapt program to learn the changes...

All went well, however i went from a solid 40psi at hot idle to the 28psi suddenly.

I also noticed my oil appears to be a little foggy looking, like it has air bubbles...
I replaced the pickup tube, but it didn't help much.


I did notice a bunch of crud in the bottom of the pan...

Now i believe that the bypass in the oil pump is stuck/has crud from the pan.
Likely sucked up when cold, and pushed right into the bypass...

I was going to leave it as is, but it's bugging the crap out of me.
:rolleyes:


So the plan this weekend, i'm moving my motorhome project out of the garage this weekend into a newly rented storage unit.
And the Tahoe is going in there.


I figure if i need to pull the pan, front diff, front cover, and oil pump...
Well then I might as well go all in! :biggun:

:Caffeine:


What i need help with is parts selection,
Oil Pump, timing chain, camshaft, head gasket, head bolts, etc.
:cheers:
 

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
19,582
Reaction score
26,255
Location
Treasure Coast, Florida
Recently i had a sudden drop of oil pressure on my 09 tahoe...
while it's still in spec, and i have DOD disabled via tune, it's still nagging at me. ...looks like i'm holding a steady 25-28psi at hot idle...

After my motor is warmed up with fresh oil, it runs about the same as yours and has since I got it. About 5000 miles later, it is down a few psi, low 20s at idle in gear. Switching oil filters was good for a few psi. My motor is the LC9 which runs a different oil pump which pumps more volume with less pressure because of the expansion of the aluminum block.


https://www.enginebuildermag.com/wp...es/03_01_2012/986163348GMGENI_00000054947.pdf
 
OP
OP
Just Fishing

Just Fishing

Can't fix stupid
Joined
Aug 30, 2020
Posts
3,842
Reaction score
8,275
Location
Utah
Main thing nagging at me is the sudden drop, and what appears to be some fine bubbles forming in the oil.

I also had my pan a tad overfilled, i decided to drain a good quart via the drain plug.
I saw what appeared to be brass sparkles...


However, that may not actually be a thing.
I had just honed the cylinder in my snow blower, and changed the oil.
Nothing in that snow blowers engine has anything to account for that color... :rolleyes:

And that pan was not exactly clean...

But it's nagging at me... lol


I'm slightly OCD when it comes to getting everything working perfectly...
I also noticed that my oil pressure over 5k rpm, will spike to 50psi after a big lag, and then will settle back down into the 40's...

After the oil pickup tube o-ring failed to fix this, i also tried two different brands of filters.
Mobil1, K&N (not the one with the nut, but still a premium), and a premium wix filter.


I figure it's worth while to toss an oil pump at it with the miles the engine has (about 180k).
(and i would like to tackle the timing chain)

And as long as i'm that deep into the engine, it's not that much more to just tackle the full delete...

I also want to look at the cam bearings while the camshaft is out, however I'm not quite sure how i'll check them with the block in the truck.... :D
If things look worn, then it's a fine time to pull the block...
Then it should get fun... "while it's out" list will grow! ;)
 

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
19,582
Reaction score
26,255
Location
Treasure Coast, Florida
Main thing nagging at me is the sudden drop, and what appears to be some fine bubbles forming in the oil.

I also had my pan a tad overfilled, i decided to drain a good quart via the drain plug.
I saw what appeared to be brass sparkles...


However, that may not actually be a thing.
I had just honed the cylinder in my snow blower, and changed the oil.
Nothing in that snow blowers engine has anything to account for that color... :rolleyes:

And that pan was not exactly clean...

But it's nagging at me... lol


I'm slightly OCD when it comes to getting everything working perfectly...
I also noticed that my oil pressure over 5k rpm, will spike to 50psi after a big lag, and then will settle back down into the 40's...

After the oil pickup tube o-ring failed to fix this, i also tried two different brands of filters.
Mobil1, K&N (not the one with the nut, but still a premium), and a premium wix filter.


I figure it's worth while to toss an oil pump at it with the miles the engine has (about 180k).
(and i would like to tackle the timing chain)

And as long as i'm that deep into the engine, it's not that much more to just tackle the full delete...

I also want to look at the cam bearings while the camshaft is out, however I'm not quite sure how i'll check them with the block in the truck.... :D
If things look worn, then it's a fine time to pull the block...
Then it should get fun... "while it's out" list will grow! ;)

Those crankcase additives have a habit of breaking sludge loose which then wreaks havoc on the oiling system. Think of little blood clots passing through the galleys and getting stuck in AFM screen, then passing through like The Blob and messing with the AFM solenoids and lifters.

Might as well yank it and put new rings and bearings in it if everything mics out and doesn't need turning!

The M1 EP filter dropped my oil pressure 2-3 psi over the K&N with the nut.

I made this list in 2017 while contemplating deleting AFM in mine, might have to update some part numbers:

upload_2020-11-3_17-15-41.png

No camshaft in this list, the ones I like are too small for most folks. Chris' Tahoe seems to like the one he selected for his. @iamdub
 
OP
OP
Just Fishing

Just Fishing

Can't fix stupid
Joined
Aug 30, 2020
Posts
3,842
Reaction score
8,275
Location
Utah
I was kinda thinking that, if the engine gets pulled... then might as well have a full service done at the machine shop...
If i'm lucky, it just needs rings and a hone.
:beer:

And yeah, i'm figuring i plugged crap up.
Atleast the screen on the oil pressure sending unit was pretty clean.
:fishing1:

I figure new valve seals and maybe springs while the heads are off.
 

iamdub

Full Access Member
Joined
Apr 23, 2016
Posts
20,821
Reaction score
44,923
Location
Li'l Weezyana
Main thing nagging at me is the sudden drop, and what appears to be some fine bubbles forming in the oil.

I also had my pan a tad overfilled, i decided to drain a good quart via the drain plug.
I saw what appeared to be brass sparkles...


However, that may not actually be a thing.
I had just honed the cylinder in my snow blower, and changed the oil.
Nothing in that snow blowers engine has anything to account for that color... :rolleyes:

And that pan was not exactly clean...

But it's nagging at me... lol


I'm slightly OCD when it comes to getting everything working perfectly...
I also noticed that my oil pressure over 5k rpm, will spike to 50psi after a big lag, and then will settle back down into the 40's...

After the oil pickup tube o-ring failed to fix this, i also tried two different brands of filters.
Mobil1, K&N (not the one with the nut, but still a premium), and a premium wix filter.


I figure it's worth while to toss an oil pump at it with the miles the engine has (about 180k).
(and i would like to tackle the timing chain)

And as long as i'm that deep into the engine, it's not that much more to just tackle the full delete...

I also want to look at the cam bearings while the camshaft is out, however I'm not quite sure how i'll check them with the block in the truck.... :D
If things look worn, then it's a fine time to pull the block...
Then it should get fun... "while it's out" list will grow! ;)


First thing is to SET A LIMIT! Either limit yourself to a dollar amount and see how far that will take you or set an honest parts and/or upgrade limit.

At ~200,035 miles, I set out to do an AFM delete with an L33 cam and all stock parts. I didn't wanna invest any more than the bare minimum into the old 5.3 since my ultimate goal is a built 6.0 or 6.2. I already had AFM disabled in a tune, and the L33 cam has the same profile as the AFM cam, just without the AFM lobes. So, it would've been a bolt-on-and-go deal. I had all the parts for the delete and new parts as a refresh (stock-replacement oil pump, timing chain, all seals/gaskets, LS6 valve springs leftover from a past project, etc.). I wanna say it was about $800 in parts and should've been finished in a weekend or two, depending on distractions. I planned to pull the engine out since I was replacing the rear main seal and rear cover gasket. Since I had to have the heads off anyway, I pulled them in the engine bay so I'd have easy access to the top four bellhousing bolts.

Right after pulling the engine out, a buddy offered me a nice mild cam for $100. Of course, this meant custom tune, possibly pushrods, maybe a slightly looser converter, etc... I decided to just roll with it. The heads were already at the shop to be cleaned, resurfaced, valve stem seals replaced and LS6 springs installed, so I just had him shave .020" off (should've went .025"-.030") and blend in the bowls for an extra ~$150. Then I decided on thinner head gaskets. Between the cam, shaved heads and thinner gaskets, I needed push rods. Factory ones flex, so I got some fat 3/8" one-piece rods as cheap insurance. New oil pump was in hand and the Dremel was nearby- so the new pump got ported/smoothed. Block was out and I didn't trust the gasket on the LS3 valley cover to seal off the AFM towers, so I tapped and plugged the towers. Capped off the AFM pressure release valve port in the oil pan since it was no longer needed. Since the engine was out and the torque converter was easily accessible and it would complement the cam, it got swapped for a CircleD 2800. Figured I may as well throw a few cheap bolt-on upgrades at the trans, so it got a Corvette servo and Sonnax Super Hold 3/4 servo. These don't apply to your 6L80E, though. Since I was already blowing money and was offered a decent deal, I added headers into the mix.

Most of this stuff was small and relatively cheap upgrades, and many of the parts can be sold or used on the 6.0+ build when that time comes, so it's not like I invested solely into a high-mileage engine that I won't have forever. This is why I didn't completely disassemble the bottom end and have the bearings replaced. If the block went to the shop for that, it would've gotten bored to 5.7L and who-knows-what more. The cam bearings looked used as expected, but not unusable. Since my oil pressure was good and was going to be even better, I figured they'd be fine for a long time. There are many 300K+ Gen4s on the road with their original cam, crank and rod bearings in place. Still, I ended up spending an additional ~$1,600 thanks to my buddy selling me that cam and due to the WIHIMAW syndrome.

I have no regrets. She runs strong and gets better fuel economy than with AFM. Oil pressure was always "good" before, like high 20s at hot idle to high 30s hot cruising. But, now it stays around 37 hot idle and 47 hot cruising. It'll almost hit 80 near the 6,000RPM redline.


So, what're your plans?!
 
Last edited:
OP
OP
Just Fishing

Just Fishing

Can't fix stupid
Joined
Aug 30, 2020
Posts
3,842
Reaction score
8,275
Location
Utah
i'm perfectly willing to drop a few k into this build.
I would like to stay right around 1k...

Should i pull the engine, i'll also replace the converter for my 6 speed... that should suck a good 500-800 from what i have skimmed over...

Looking at just a basic AFM disable kit with cam say at Texas speed, i'm looking at like $900 right there.

What i would really like to do is to clone someone's build, especially if i can "borrow" a copy of their tune to copy paste onto my stock tune...
otherwise i'm factoring trying to find someone competent to do the tune, and it would be awesome if I could use my current hp tuners license to save me a few bucks...
:D

Pretty much I'm open to ideas, but would like to stay under 2500 max.
Always room to expand...


My vette build for instance, i started with like 2k budget, but that expanded.
Head ports required headers, that turned into a full exhaust...
Blew the trans due to a pos aftermarket tv cable, that turned into one hell of a quick shifting trans.
A riot when shifting manually, 9.5in 3200 stall = very easy to spin the tires... :angels2:
it's also obnoxious/loud.
I love that car.
:beer:
However, that car is exempt from emissions...

The Hoe is not. :nolol:
 
OP
OP
Just Fishing

Just Fishing

Can't fix stupid
Joined
Aug 30, 2020
Posts
3,842
Reaction score
8,275
Location
Utah
I would like to play around with hp tuners more...
I understand there is an addon in order to do some fuel learning, but i haven't looked much into it as of yet...
 

iamdub

Full Access Member
Joined
Apr 23, 2016
Posts
20,821
Reaction score
44,923
Location
Li'l Weezyana
You have HPT and you'll be inside it already- you may as well get a performance cam and all the little supporting mods to one-and-done it. Getting the short block rebuilt (bearings, rings and honing) are up to you. If it's been maintained well for that 180K miles, you may decide it's not a necessity and can save the cash or spend it elsewhere in the build. My cylinder walls looked great and compression across the board was 210-215 psi with 6 rotations, reaching that after 3 rotations. Although, I have to say that I can't ascertain that my short block was original.
 
OP
OP
Just Fishing

Just Fishing

Can't fix stupid
Joined
Aug 30, 2020
Posts
3,842
Reaction score
8,275
Location
Utah
I figure i'll take a good look at the bore while i have the heads off.
If it looks like the cylinder needs to be bored or honed, then the block will likely come out.
Same for the cam bearings, depending on how they look.
I'm not totally sure how to check them with them in the truck, but i'm sure there is a youtube video to cover the basics....

i'm hoping i won't have to pull the engine.
It would be great if this turned into a 2-3 weekend task (taking it nice and slowish) :D

more power would be great, i would like a slightly more noticeable idle as well.

I would like to still use 87/85 octane...
 

Forum statistics

Threads
131,755
Posts
1,856,280
Members
96,017
Latest member
CountryRoads
Top