What did you do to your NBS GMT800 Tahoe/Yukon Today?

[Tonyrodz]

I was finally able to check my oil pressure with a manual gauge. That was an ordeal in itself.......
The oil pressure gauge kit that I purchased has about a dozen different adapters EXCEPT the one for LS engines!! After a quick Google search, it seems many oil gauge manufacturers do NOT include this adapter. Rather than order the needed adapter and wait several MORE days before I can test it, I decided to just make my own adapter by drilling and threading the old oil pressure sensor that I removed from the engine. Other than the cheap Harbor Freight tap handle breaking in the process, this plan worked out great. I was finally able to test my oil pressure once and for all and much to my dismay, the manual gauge reads the same exact pressure as the dash gauge, around 8-10 psi. I just ordered a Melling high volume oil pump abs screen kit, which should be here Monday or Tuesday, along with all the gaskets and seals that will need to be replaced in the process. So, the saga continues.........

I had the same exact issue in my Express van. Put a HV Melling pump and O ring in it. Internally, the motor has so much sludge, it looks like the oil was never changed. I bought it with 110k on it. I'm religious with oil changes. I do them every 2500 miles. Oil pressure is fantastic now. Iirc cold pressure is around 60, and hot is around 50.

I did it with help from my buddy, in his shop. Lol. Even using his lift for the a/c tensioner & belt, my back is an absolute wreck. I had planned to do it all myself, but my back just can’t take anything these days.

Did you get it tuned to turn the fans on? Or do you have it wired to a manual switch? I still need to do mine.

Oh man, that blows! I always knock one of the lug studs out and then use a bolt through the stud hole with a nut on the back side to push the hub free. Not gonna work there unfortunately...

I finally got it off with an air hammer. Literally took 2 mins, after banging on it awhile with a mini sledge.

 

[live2pull]

I did it with help from my buddy, in his shop. Lol. Even using his lift for the a/c tensioner & belt, my back is an absolute wreck. I had planned to do it all myself, but my back just can’t take anything these days.

Very nice job. A mod I always wanted to do. Sorry to hear about the back.

 

[Walchit]

I have a feeling my low oil pressure is sludge induced. Maybe I should grab one of those HV pumps.

 

[ScottyBoy]

I have a feeling my low oil pressure is sludge induced. Maybe I should grab one of those HV pumps.

I wonder if there's a chance that sludge is what's causing my low pressure. I replaced my oil pan gasket, pickup tube and O-ring in 2017. There was a LOT of sludge, but I sort of expected that because I ran a bottle of engine flush right before I dropped the pan. I'm pretty consistent with my oil changes, but I only go by the mileage, not the time. I have left the same oil in there for almost a year one time, but it had less than 4k miles on it, and even though it wasn't even 4k miles, the oil looked BAD. On average tho I seem to replace it about every 4-5k miles which is around 7-8 months for me. I usually run Amsoil XL series and a WIX filter.

 

[Rocket Man]

I wonder if there's a chance that sludge is what's causing my low pressure. I replaced my oil pan gasket, pickup tube and O-ring in 2017. There was a LOT of sludge, but I sort of expected that because I ran a bottle of engine flush right before I dropped the pan. I'm pretty consistent with my oil changes, but I only go by the mileage, not the time. I have left the same oil in there for almost a year one time, but it had less than 4k miles on it, and even though it wasn't even 4k miles, the oil looked BAD. On average tho I seem to replace it about every 4-5k miles which is around 7-8 months for me. I usually run Amsoil XL series and a WIX filter.

Definitely could be. You’re pulling the pan when you do your oil pump right? You can do the pump without doing it but it’s easier to pull the pan. That way you can clean the screen and see if there’s sludge in there.

 

[Tonyrodz]

My OP went to 0 in my van. Revving it would move the needle maybe to 10 psi--if that. It also developed a low knock.
O ring was fine, but swapped it out anyway. Here's what it looked like.
The sludge in the pan was really thick. Unfortunately I don't have a pic of the pick up screen, but it had gunk in the screen. It was pretty bad.

 

[Rocket Man]

My OP went to 0 in my van. Revving it would move the need6maybe to 10 psi--if that. It also developed a low knock.
O ring was fine, but swapped it out anyway. Here's what it looked like. View attachment 353426View attachment 353427View attachment 353428View attachment 353429View attachment 353430
The sludge in the pan was really thick. Unfortunately I don't have a pic of the pick up screen, but it had gunk in the screen. It was pretty bad.

Damn. I HATE sludge! No more issues after that?

 

[Jim Z71]

I drove my Tahoe to work EARLY this morning. Then home this afternoon. The best part! Not too eventful.

 

[ratled]

New Skips for it today. Cooper AT 3. Looking forward to see how they do in the snow soon enough. Next on the list is fluid for both difffs and the transfer case.............

 

[ScottyBoy]

Definitely could be. You’re pulling the pan when you do your oil pump right? You can do the pump without doing it but it’s easier to pull the pan. That way you can clean the screen and see if there’s sludge in there.

Yeah, I'm dropping the pan. I have a RWD so it's super easy, no 4WD stuff in the way to deal with. Also, I ordered a pump with a new screen/inlet tube so both are getting replaced even though I replaced the inlet tube in 2017. I had a Melling high volume oil pump in my shopping cart on Rockauto, then a day later when I went to actually place my order, my shopping cart was empty and the Melling high volume pump miraculously disappeared off the site. In it's place was a "kit" which was the same pump but also includes the screen/inlet tube, and said kit is about $30 more than the pump was by itself. So they basically force you to buy the inlet tube, Lol.