How to diagnose lifter failure before it really goes south?

[DK91105]

CTRL + ALT + DELETE

[DK91105]

Took the day off and made some big progress on the reassembly.   Man torquing those head bolts is not fun leaning over the radiator support.  Wore me smooth out today. 

Edited November 20, 2024 by DK91105

[Colin Zwaschka]

On 11/16/2024 at 12:57 PM, DK91105 said:

Here's proof you can do this with out a pan drop or pulling the oil pump forward.  Going back on was easier than removal.  Nailed the orientation in 1 try.    New cam and retainer plate installed prior obviously.  

It's doable. Also nailed timing on first try. 

[DK91105]

9 hours ago, Colin Zwaschka said:

It's doable. Also nailed timing on first try. 

 

 

Went on easier than it came off was my experience.   Looks like you are now at the point I was before yesterday's work.   Prep, prep, prep your surfaces.  Also make sure you chase all of the head bolt holes. I used a M12 x 1.75 long thread chaser from ARP.  P/N: 912-0016.  Attach a small hose to your shop vacuum and get in each bore to the very bottom and get all liquids / trash out.  I used a small $20 amazon special bore scope that plugs into my phone to verify all liquids were out of the head bolt holes.   This will take some time as getting the deck / head surfaces ready for reassembly is quite tedious work.  I found that acetone really cuts the old gasket material on the surfaces exceptionally well.  Carb cleaner I've seen people use in videos didn't even touch it.  

[Colin Zwaschka]

1 hour ago, DK91105 said:

 

 

Went on easier than it came off was my experience.   Looks like you are now at the point I was before yesterday's work.   Prep, prep, prep your surfaces.  Also make sure you chase all of the head bolt holes. I used a M12 x 1.75 long thread chaser from ARP.  P/N: 912-0016.  Attach a small hose to your shop vacuum and get in each bore to the very bottom and get all liquids / trash out.  I used a small $20 amazon special bore scope that plugs into my phone to verify all liquids were out of the head bolt holes.   This will take some time as getting the deck / head surfaces ready for reassembly is quite tedious work.  I found that acetone really cuts the old gasket material on the surfaces exceptionally well.  Carb cleaner I've seen people use in videos didn't even touch it.  

Yeah. Next up is cleaning surfaces. My least favorite part.

[DK91105]

Well  I'm all done, back together, and running.   Here's a few final thoughts about this job now that it's all done.  

 

If you have a decently stocked toolbox and your back is in decent shape you can do this by yourself without pulling the engine. You will need a couple specialty tools but nothing crazy.  

 

The GM cam that is recommended for this job if you delete the DFM is called a "L8T" cam.  I was concerned that the engine would need actual tuning but that is not the case, It runs fine.  You will need someone with HP tuners to turn off the DFM and tell it to ignore all codes associated with it that would cause a CEL. 

 

Beyond all that, if you have it apart already, it's a great time to go ahead and do a tuneup.  I put new plugs, wires, belts,  and hoses on since they were off anyways.  This of course adds some cost but worth it to me.  I also did a couple of frivolous things like put a new water pump assembly on and purchased my own HP tuners.

 

All in all I have just over $3500 in the whole job including all parts, fluids, machine work on the heads, catch can, and the HP tuners stuff.   Compared to the one quote I received from a GM dealership it's quite a savings.  They quoted me over $10k for the job if the cam was bad which turned out it was and that was just putting it back the way it was with DFM lifters.  

Edited November 25, 2024 by DK91105

[DK91105]

Quick little update, I have put about 100 miles on it since I finished it up. I don't know if it was cleaning all the gunk / buildup off of the valves, fresh plugs and wires, the DFM delete, or a combo of all of it but it certainly feels a lot more peppy.  Also at idle I have had to check several times if it had turned itself off. Its running so smooth its impossible to tell its even running at all 

 

Speaking of turning itself off..  I disabled auto start / stop in HP tuners. However the light on the button itself is still on. I believe the setting in HP tuners just denies the condition that would allow it to do the auto shut off but the truck is still looking. So basically it looks like its active but it will never shut itself off. I know with the Pulsar LT module it actually makes the truck think the button has been pushed and you get the notification on the dash and the light is turned off on the button. Just a little bit of info I found interesting. 

[KARNUT]

This thread brings back memories of my younger days. The only difference the tear down was for performance modifications. Not longevity modifications removing junk that shouldn’t be there in the first place. As far as my lifter tap that happens only when the temperature falls below freezing. I just don’t start the 23 year old truck with the original engine until it warms up. You now made your ride bulletproof, good work.

[Colin Zwaschka]

What pushrod length did you put back in? You used the LS7 lifters with the L8T cam, right?

 

ETA: You also took 0.003 off the heads. Assuming stock head gasket thickness?

Edited November 30, 2024 by Colin Zwaschka

[Polo08816]

On 11/25/2024 at 11:51 AM, DK91105 said:

Well  I'm all done, back together, and running.   Here's a few final thoughts about this job now that it's all done.  

 

If you have a decently stocked toolbox and your back is in decent shape you can do this by yourself without pulling the engine. You will need a couple specialty tools but nothing crazy.  

 

The GM cam that is recommended for this job if you delete the DFM is called a "L8T" cam.  I was concerned that the engine would need actual tuning but that is not the case, It runs fine.  You will need someone with HP tuners to turn off the DFM and tell it to ignore all codes associated with it that would cause a CEL. 

 

Beyond all that, if you have it apart already, it's a great time to go ahead and do a tuneup.  I put new plugs, wires, belts,  and hoses on since they were off anyways.  This of course adds some cost but worth it to me.  I also did a couple of frivolous things like put a new water pump assembly on and purchased my own HP tuners.

 

All in all I have just over $3500 in the whole job including all parts, fluids, machine work on the heads, catch can, and the HP tuners stuff.   Compared to the one quote I received from a GM dealership it's quite a savings.  They quoted me over $10k for the job if the cam was bad which turned out it was and that was just putting it back the way it was with DFM lifters.  

 

Would turning off the CELs prevent someone's vehicle from passing OBD2 style emissions test?

[DK91105]

1 hour ago, Colin Zwaschka said:

What pushrod length did you put back in? You used the LS7 lifters with the L8T cam, right?

 

ETA: You also took 0.003 off the heads. Assuming stock head gasket thickness?

I reused the stock pushrods.  No change in length is necessary with ls7 lifters and the L8T cam.  They removed .003" from the heads and I used stock thickness head gaskets.  It's not enough of a difference to really matter.  If you go more, you might start to get into the range of having to take it into consideration.   I'd ask the machine shop to be sure.  

Edited November 30, 2024 by DK91105

[DK91105]

4 hours ago, Polo08816 said:

 

Would turning off the CELs prevent someone's vehicle from passing OBD2 style emissions test?

I have heard no, the DFM system isn't looked at with that style of emissions test.  My inspection literally expires today so I'll let you know what happens in the next day or so.  

 

I had to edit my comment, I just went back out and plugged in my OBDII reader and some of the items are not showing "ready"  I'm going to look into it.  

Edited November 30, 2024 by DK91105

[DK91105]

On 11/30/2024 at 8:54 AM, Polo08816 said:

 

Would turning off the CELs prevent someone's vehicle from passing OBD2 style emissions test?

I figured it out. All emissions systems finally went into a "ready" status and it passed emission inspection in TX which is a OBDII plug in inspection.  So to answer your question, no this will not cause a truck to fail emissions inspection. 

Edited December 9, 2024 by DK91105

[Offroad9730]

GM should be ashamed of themselves but they don't give a rats ass.

That is A HELLUVA lot of work !  I've seen it done.  And that's just the DIS-assembly.  Then it all has to be put back together...........codes all checked.  blah blah blah

Myself...........I'd drive it until it blew.  Then drop a performance crate engine in it WITHOUT any fuel management bullshit.  I have a 2020 with a 5.3.  28,000 miles.  Lucky so far I guess,  BUT I

Change the oil A LOT.  It's all a guy can do, or  what you're doing, or........get a crate and drop it in.

GM really dropped the ball on this one.  Isn't there a class action law suit going yet?

[Gangly]

On 11/19/2024 at 6:33 PM, DK91105 said:

Took the day off and made some big progress on the reassembly.   Man torquing those head bolts is not fun leaning over the radiator support.  Wore me smooth out today. 

I agree.  The driver's side rear and passenger's side rear WORE ME OUT.  The angles are just all wrong for torqueing and adding additional degrees of turn.  I wound up moving a bench to the front of the truck and standing on that after my ribs and stomach got too sore to lean over the radiator support.