What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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.

iamdub

Full Access Member
Joined
Apr 23, 2016
Posts
20,821
Reaction score
45,012
Location
Li'l Weezyana
You've done your research on this so I'm asking you. Can you leave the stock cam and change over to LS-7 lifters to do DOD delete or do you have to change to a non DOD cam?

It'll "run", but those four AFM cylinders will have lower compression and the imbalanced firing will throw misfire codes. You can tune it to help it and maybe avoid the codes, but the engine will still feel stupid.

For mine, I bought a Gen3 L33 cam since it has identical specs as the stock Gen4 AFM cam, but with all lobes matching. For that cam I got a 3-bolt cam sprocket with the Gen4 trigger setup, it's a GM part. There are center bolt Gen4 non-AFM cams but the specs aren't quite the same. Close enough to run without a custom tune, though.

Since you brought it up, my L33 cam may be up for grabs. A buddy has a TSP Stage2 low lift truck cam he's offering to me for next to nothing. I wanted to avoid custom tuning to keep costs to a minimum, but I'm having the heads worked over so I'll need a tune anyway. Since I'm already getting a tune, the cam would be "free/cheap" power.
 
Last edited:

pwtr02ss

Full Access Member
Joined
Apr 1, 2013
Posts
13,900
Reaction score
32,275
Location
Tennessee
It'll "run", but those four AFM cylinders will have lower compression and the imbalanced firing will throw misfire codes. You can tune it to help it and maybe avoid the codes, but the engine will still feel stupid.

For mine, I bought a Gen3 L33 cam since it has identical specs as the stock Gen4 AFM cam, but with all lobes matching. For that cam I got a 3-bolt cam sprocket with the Gen4 trigger setup, it's a GM part. There center bolt Gen4 non-AFM cams but the specs aren't quite the same. Close enough to run without a custom tune, though.

Since you brought it up, my L33 cam may be up for grabs. A buddy has a TSP Stage2 low lift truck cam he's offering to me for next to nothing. I wanted to avoid custom tuning to keep costs to a minimum, but I'm having the heads worked over so I'll need a tune anyway. Since I'm already getting a tune, the cam would be "free/cheap" power.

Thats what I Thought. Thank you for the info. I'll probably just hope to get another 50-100k out of a lifter swap. lol
 

R3cord303

Posse In Effect
Joined
Feb 28, 2019
Posts
1,166
Reaction score
1,421
Location
Oregon Valley
It'll "run", but those four AFM cylinders will have lower compression and the imbalanced firing will throw misfire codes. You can tune it to help it and maybe avoid the codes, but the engine will still feel stupid.

For mine, I bought a Gen3 L33 cam since it has identical specs as the stock Gen4 AFM cam, but with all lobes matching. For that cam I got a 3-bolt cam sprocket with the Gen4 trigger setup, it's a GM part. There center bolt Gen4 non-AFM cams but the specs aren't quite the same. Close enough to run without a custom tune, though.

Since you brought it up, my L33 cam may be up for grabs. A buddy has a TSP Stage2 low lift truck cam he's offering to me for next to nothing. I wanted to avoid custom tuning to keep costs to a minimum, but I'm having the heads worked over so I'll need a tune anyway. Since I'm already getting a tune, the cam would be "free/cheap" power.
low lift stg 2 is 10/10. I may have to get redynoed and we’ll compare numbers
 

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
21,299
Reaction score
30,254
Location
Treasure Coast, Florida
lol, no it was pieces of rebar or something similar, I'm pretty sure they are pieces of rebar for doing driveways since they are about 18"

Yikes, we've had people impaled with rebar down here; falling out of an uncovered truck and going through a windshield. Count your blessings. No tire damage?
 

iamdub

Full Access Member
Joined
Apr 23, 2016
Posts
20,821
Reaction score
45,012
Location
Li'l Weezyana
Thats what I Thought. Thank you for the info. I'll probably just hope to get another 50-100k out of a lifter swap. lol

Lifter swap as in swapping in regular lifters or replacing AFM lifters? There's an updated design of AFM lifter and installing those would make it a plug-and-play deal and you could keep your current cam, valley cover, etc. No custom tuning would be necessary. Having new lifters and keeping the system turned off may very well give you another 100K+ miles. I'd enable AFM to cycle the lifters for a while right after installing them, though. If you wanna do it on the cheap, this would just cost you the lifters, trays and gaskets.
 

iamdub

Full Access Member
Joined
Apr 23, 2016
Posts
20,821
Reaction score
45,012
Location
Li'l Weezyana
low lift stg 2 is 10/10. I may have to get redynoed and we’ll compare numbers

I'm trying to not get my hopes up a whole lot since there are some extenuating circumstances beyond our controls, but the deal's looking very possible. I really doubt I'll have dyno figures, but I live less than 5 miles from a 1/4 mile strip so I can calculate from that.

Now I'm wishing I had gotten some baseline runs at the track.






...Hmmm. I'm 8 miles shy of 200K. It'd be cool to hit 200K miles at WOT on the big end of the strip!
 

Doubeleive

Wes
Supporting Member
Joined
Nov 7, 2017
Posts
30,563
Reaction score
48,043
Location
Stockton, Ca.
Yikes, we've had people impaled with rebar down here; falling out of an uncovered truck and going through a windshield. Count your blessings. No tire damage?
yes, 2 pieces impaled the truck and the 3rd impaled the tire then spun and ripped the splash guard almost in half, I posted pictures yesterday. the tire shop was able to fix the Tire with a patch
 

pwtr02ss

Full Access Member
Joined
Apr 1, 2013
Posts
13,900
Reaction score
32,275
Location
Tennessee
Lifter swap as in swapping in regular lifters or replacing AFM lifters? There's an updated design of AFM lifter and installing those would make it a plug-and-play deal and you could keep your current cam, valley cover, etc. No custom tuning would be necessary. Having new lifters and keeping the system turned off may very well give you another 100K+ miles. I'd enable AFM to cycle the lifters for a while right after installing them, though. If you wanna do it on the cheap, this would just cost you the lifters, trays and gaskets.

Yes, that's the plan. Just spend the extra money on AFM lifters and save the labor. It had the "updated" lifters installed at around 30k miles. They have lasted well. I'm at 198k, maybe close to 199k.
 
Last edited:

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
21,299
Reaction score
30,254
Location
Treasure Coast, Florida
...Hmmm. I'm 8 miles shy of 200K. It'd be cool to hit 200K miles at WOT on the big end of the strip!

Yeah Chris! Get some runs in this week to baseline the truck!

I think we'll be up there towards the end of May, maybe we can get our trucks together at the track for some runs and photos?
 

89Suburban

Bull in the china shop
Space X Supporting Member
Joined
Jan 10, 2013
Posts
17,856
Reaction score
50,895
Location
SE PA
I generally drive using the other 99.86% of the windshield that the wipers cover. That small area on the far end of the passenger side doesn't make a damn to me.


Also because of the edge lift, you wind up getting this dirt/dust smudge mark on the outer edge of that wiper path up the windshield instead of a clean line and looks like chit. SO there... :p
 

Rocket Man

Mark
Supporting Member
Joined
Dec 25, 2014
Posts
26,679
Reaction score
52,949
Location
Oregon
Preparing for a new air management system on the Silverado.

41FAA49D-D938-4A48-B285-1543FBDB0718.jpeg EBD0D31A-1EE9-40F8-B850-ECA5158B50BC.jpeg 15AB1B17-B134-45BD-BAA4-427250DB9AFF.jpeg
 

iamdub

Full Access Member
Joined
Apr 23, 2016
Posts
20,821
Reaction score
45,012
Location
Li'l Weezyana
Yeah Chris! Get some runs in this week to baseline the truck!

I think we'll be up there towards the end of May, maybe we can get our trucks together at the track for some runs and photos?

If y'all make it up this way, then come on with it! What's funny is that sometime towards the end of May, we may be headed to Tampa! lol
 

iamdub

Full Access Member
Joined
Apr 23, 2016
Posts
20,821
Reaction score
45,012
Location
Li'l Weezyana
Also because of the edge lift, you wind up getting this dirt/dust smudge mark on the outer edge of that wiper path up the windshield instead of a clean line and looks like chit. SO there... :p

80MPH + rain seems to wash that off just fine. Coincidentally, it just so happens that during a rain is actually when I'm running my wipers! How convenient!
 

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
21,299
Reaction score
30,254
Location
Treasure Coast, Florida
Paint Correction today! My girls used a Dupli-Color pen to clean out some rock chips and filled them in, along with a couple of scratches from the woods and mailboxes striking the truck. Also had a little patch of clear coming off the front bumper, so we wet-sanded that with 800 grit sandpaper and then taped it off and put 3 coats of Dupli-Color clear on top of that. In two days we'll wet-sand that area and maybe some of the scratches with 2000 grit sandpaper.
 

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
21,299
Reaction score
30,254
Location
Treasure Coast, Florida
If y'all make it up this way, then come on with it! What's funny is that sometime towards the end of May, we may be headed to Tampa! lol

I was supposed to be in Tampa today, a relative had surgery at the Moffitt Cancer Center. I'll keep ya posted on when plans get finalized to head up your way.
 

HiHoeSilver

Away!
Joined
Feb 28, 2017
Posts
10,918
Reaction score
14,578
Location
Chicago
Paint Correction today! My girls used a Dupli-Color pen to clean out some rock chips and filled them in, along with a couple of scratches from the woods and mailboxes striking the truck. Also had a little patch of clear coming off the front bumper, so we wet-sanded that with 800 grit sandpaper and then taped it off and put 3 coats of Dupli-Color clear on top of that. In two days we'll wet-sand that area and maybe some of the scratches with 2000 grit sandpaper.

Take any pics of the spots?
 

Forum statistics

Threads
137,781
Posts
1,992,153
Members
102,777
Latest member
wwiizz
Back
Top