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

[Sam Harris]

Took it for a shakedown run and to test the exhaust, then to get dinner, then to Walmart.

The mufflers are actually quieter than before, when I had cats, as I thought they should be. I just couldn't figure out how having an extra 22" of muffler wouldn't make much a difference. The noise is what little leaks past the cutout since it doesn't seal up 100%. I stuffed a couple wadded-up rags in it and went for a test drive. It was almost as quiet as stock. I floored it and, as expected, the rags shot out somewhere around 5,000 RPM and the noise was back. I turned around to retrieve the rags and went home, satisfied that all that muffler work actually was a success. I have a plan and parts to move forward in this, but it can wait until cooler weather.


... Besides, I now have something much more pressing to be concerned with:

A couple hours ago, on my way back from Walmart, I turned onto the road that my street is off of. As I accelerated, I heard and a sharp clunk and felt it in the steering wheel. I slowed and looked in the mirror to see if I ran over something, but the road was clear. I let it idle forward and could hear an intermittent clinking. Stopped and revved it in neutral to see if it was the trans- nope. It only does it when rolling. I idled the ~3/8 mile home and parked it. I'll pull the front wheels tomorrow and assess. It's either a blown hub or a broken hub bolt. The hubs have always felt and sounded fine, so I doubt one would just go from fine to this bad with no warning. I think I know what it is since there's nothing else up there to cause these symptoms.

Sounds like great progress man! Too bad we can’t hear it to have a better idea.. but sorry about the mystery noise. I’m hopeful it’s a fairly easy fix.

 

[osiris94ej]

I like these. What rim is that?

MKW M96. 20x9 +15mm

Sent from my SM-N950U using Tapatalk

 

[iamdub]

I guess you don’t have a diff up there to worry about. Or CV axles.

Nope! Burnouts in reverse all day long...

 

[iamdub]

Sounds like great progress man! Too bad we can’t hear it to have a better idea.. but sorry about the mystery noise. I’m hopeful it’s a fairly easy fix.

I was gonna wait 'til I had the cutout wired up before I made a video. But I may go ahead and upload some for comparison.

Speaking of, does anyone know how I could edit videos on my phone before uploading to YouTube? I'd much rather upload one video that has the before and after (rag stuffed in cutout dump) comparisons in it.

 

[08z71bgm]

I was gonna wait 'til I had the cutout wired up before I made a video. But I may go ahead and upload some for comparison.

Speaking of, does anyone know how I could edit videos on my phone before uploading to YouTube? I'd much rather upload one video that has the before and after (rag stuffed in cutout dump) comparisons in it.

Only thing you can do without downloading an app on an iPhone is change the length. I’m unsure what an android can do. I’m sure you could find editing app for any platform.

 

[wjburken]

Speaking of, does anyone know how I could edit videos on my phone before uploading to YouTube? I'd much rather upload one video that has the before and after (rag stuffed in cutout dump) comparisons in it.

On an iPhone, you can use the app Clips or iMovie.

 

[08z71bgm]

On an iPhone, you can use the app Clips or iMovie.

Well shit I forgot about iMovie!!!

 

[iamdub]

On an iPhone, you can use the app Clips or iMovie.

Well shit I forgot about iMovie!!!

I wasn't sure if there was a way to do this type of editing (combining videos?) with the YouTube app. I tend to miss things in plain sight. I'll check out those other apps. Thank ya!

 

[992dr]

I finally changed my abs sensor, its only been a year or three.

Anybody have experience with rear mains?
My mechanic said I have some signs of a leaky rear main and while changing my sensor took a peak. There's definitely some drips on the rear of the oil pan, bell housing and the sway bar. My wife told me the spot on the driveway are pretty noticeable to.

 

[iamdub]

I finally changed my abs sensor, its only been a year or three.

Anybody have experience with rear mains?
My mechanic said I have some signs of a leaky rear main and while changing my sensor took a peak. There's definitely some drips on the rear of the oil pan, bell housing and the sway bar. My wife told me the spot on the driveway are pretty noticeable to.

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Super easy to replace once you have the transmission pulled away and flexplate removed.

For an in-car replacement, I highly recommend using a rear cover alignment tool. Might wanna check that oil pan gasket while you're there. Actually, the oil pan should go on after the rear cover, meaning it should at least be loosened to hang down a little as to not push upward on the rear cover while you're centering it. At that point, you may as well replace the oil pan gasket. Which, at that point, you may as well replace the oil pump pickup tube O-ring.

 

[Sam Harris]

Super easy to replace once you have the transmission pulled away and flexplate removed.

For an in-car replacement, I highly recommend using a rear cover alignment tool. Might wanna check that oil pan gasket while you're there. Actually, the oil pan should go on after the rear cover, meaning it should at least be loosened to hang down a little as to not push upward on the rear cover while you're centering it. At that point, you may as well replace the oil pan gasket. Which, at that point, you may as well replace the oil pump pickup tube O-ring.

Thanks for the tips. I presume this all applies to the GMT800 platform as well..?

 

[08z71bgm]

Well I just got a p2270 code. Anyone get this or have some ideas where to start looking at?

 

[PG01]

Well I just got a p2270 code. Anyone get this or have some ideas where to start looking at?

You pull or break any wires on the o2 sensor doing the trans pan? If you unplugged check connector....

 

[08z71bgm]

You pull or break any wires on the o2 sensor doing the trans pan? If you unplugged check connector....

No. Didn’t do anything near them. No prybar in that area at all. When I got the truck tho I know the CEL was cleared. This could be why but was told that the tpms threw a code and had it fixed the day before.

 

[Doubeleive]

No. Didn’t do anything near them. No prybar in that area at all. When I got the truck tho I know the CEL was cleared. This could be why but was told that the tpms threw a code and had it fixed the day before.

lol, tpms won't even show as any kind of code, it's a dummy light like the brake light, it's commanded on or not depending on data feedback

 

[08z71bgm]

lol, tpms won't even show as any kind of code, it's a dummy light like the brake light, it's commanded on or not depending on data feedback

Yeah I figured as much. Oh well. At least I’m mechanically inclined so I can fix it myself.

 

[Doubeleive]

Yeah I figured as much. Oh well. At least I’m mechanically inclined so I can fix it myself.

how many miles on it?

 

[89Suburban]

Can you guys see this bump stop pounding away on my brake cables? Causing another potential repair because I see the one cable sheath looks to be busted open and some rust on it?


Does anybody have pics of that area on your truck and how it looks like they should be routed??? Something is not right there.

 

[George B]

Mine go under the axle.

 

[89Suburban]

Mine go under the axle.

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**** me!!!!!!!!!!!! Thanks.