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

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iamdub

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Today, after sleeping in and dragging ass with breakfast and coffee all morning, I finally got outside around 1230 to replace the fuel pump. At 1400, it was idling on the lift as I walked underneath to check for leaks, etc.


My lift table was a little short, so I added some wooden blocks:

img_5962-jpg.278795



Only took about 30 minutes to get to this point:

img_5964-jpg.278796



Original compared to the new Delphi. I hope the change in design is an improvement:

img_5968-jpg.278797



Comfortable working height. I disconnected and blew out all the lines to ensure there weren't any remaining carbon pellets:

img_5971-jpg.278798





I replaced the pump because the Tahoe would sputter under hard acceleration, starting just under a 1/4 tank and would get progressively worse. I thought the bucket wasn't staying filled and it was losing fuel when it sloshed to the back under hard acceleration. After all this, I'm now thinking that my problem wasn't the bucket not holding fuel. When I started, my gauge was reading a hair over 1/4 tank. When I removed the original pump, the fuel level in the bucket was higher than what was in the tank, indicating that it was NOT leaking. Also, the tank was lighter than I expected. 1/4 tank of fuel should be almost 40lbs, but the tank felt much lighter than this as I wrestled it around to drop it. 40lbs isn't much, but when it's overhead and sloshing around, you'd feel it. When I backed out of the shop, running on the new pump, my gauge was reading about 1/16 tank. Now I'm thinking the level sensor was inaccurate and I was actually out of fuel- "running on fumes" as the saying goes. I went for a test drive, giving it a few WOT starts from a dig and from ~20mph so it'd downshift and accelerate at its hardest. Didn't miss a beat.
 
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cfmistry

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Dorman "updated" valve cover... leaking after 2 years?

Long story kept long, the ticking from my engine had been slowly getting louder over the years. I knew I had some broken manifold bolts, so I took it to a muffler shop to give me an estimate on the job.

While looking the truck over from underneath (and idling), sparkplug #5 was jumping around like it was about to fall out. The tech said "looks like you have a misfire, you should get that sorted out first." I went home and sure enough, plugs #5,7 were both very loose (easily removed with my fingers).

The plugs themselves looked fine but I did note a lot of oil in the area. Turns out my driver's side Dorman valve cover (with the updated baffle design) is leaking. I read around on Amazon and it turns out their gaskets are junk and routinely do this after some time (most posts note 2 years). Heads up for you other guys with this product. I re-torqued my plugs but I am sure the oil dripping on them helped them come out; time to buy the GM part like I should have the first time around!
 
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89Suburban

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Today, after sleeping in and dragging ass with breakfast and coffee all morning, I finally got outside around 1230 to replace the fuel pump. At 1400, it was idling on the lift as I walked underneath to check for leaks, etc.


My lift table was a little short, so I added some wooden blocks:

img_5962-jpg.278795



Only took about 30 minutes to get to this point:

img_5964-jpg.278796



Original compared to Denso. I hope the change in design is an improvement:

img_5968-jpg.278797



Comfortable working height. I disconnected and blew out all the lines to ensure there weren't any remaining carbon pellets:

img_5971-jpg.278798





I replaced the pump because the Tahoe would sputter under hard acceleration, starting just under a 1/4 tank and would get progressively worse. I thought the bucket wasn't staying filled and it was losing fuel when it sloshed to the back under hard acceleration. After all this, I'm now thinking that my problem wasn't the bucket not holding fuel. When I started, my gauge was reading a hair over 1/4 tank. When I removed the original pump, the fuel level in the bucket was higher than what was in the tank, indicating that it was NOT leaking. Also, the tank was lighter than I expected. 1/4 tank of fuel should be almost 40lbs, but the tank felt much lighter than this as I wrestled it around to drop it. 40lbs isn't much, but when it's overhead and sloshing around, you'd feel it. When I backed out of the shop, running on the new pump, my gauge was reading about 1/16 tank. Now I'm thinking the level sensor was inaccurate and I was actually out of fuel- "running on fumes" as the saying goes. I went for a test drive, giving it a few WOT starts from a dig and from ~20mph so it'd downshift and accelerate at its hardest. Didn't miss a beat.


Man I wish I had a lift, Nice work bro.
 

iamdub

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Dorman "updated" valve cover... leaking after 2 years?

Long story kept long, the ticking from my engine had been slowly getting louder over the years. I knew I had some broken manifold bolts, so I took it to a muffler job to give me an estimate on the job.

While looking the truck over from underneath (and idling), sparkplug #5 was jumping around like it was about to fall out. The tech said "looks like you have a misfire, you should get that sorted out first." I went home and sure enough, plugs #5,7 were both very loose (easily removed with my fingers).

The plugs themselves looked fine but I did note a lot of oil in the area. Turns our my driver's side Dorman valve cover (with the updated baffle design) is leaking. I read around on Amazon and it turns out their gaskets are junk and routinely do this after some time (most posts note 2 years). Heads up for you other guys with this product. I re-torqued my plugs but I am sure the oil dripping on them helped them come out; time to buy the GM part like I should have the first time around!

So, the cover is fine, it's just the gasket that's crap and an OEM one should be used?
 

cfmistry

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So, the cover is fine, it's just the gasket that's crap and an OEM one should be used?

That is what I read from most reviewers. Some still had leaks with a new FelPro gasket though, so not sure what that’s about. I can tell you my right gasket and cover are original and leak-free at 183k miles though.
 

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