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

[Rocket Man]

For what it's worth mine is a 2005 flex fuel and does not have a separate FPR or a (serviceable) fuel filter.

Well. I wonder if there’s a way to find out from the RPO codes?

 

[iddqd]

Strange, my FPR is integrated into my fuel pump and is nothing like what's shown in the video. In older GMT800's, the FPR was located on the fuel rail close to the firewall and was easy to access and replace. I had to replace my fuel pump around 120k miles because the FPR was failing, and since it was built into the fuel pump assembly I didn't have a choice but to replace the whole thing.

In 2004 or 2005 GM went from return to return-less system. It depends on the production year of your rig. With the reurnless system they also eliminated a fuel filter under the belly of the truck, and change fuel injector flow map.

In return system, the flow numbers are constant regardless the intake manifold vacuum, and the fuel regulator makes necessary adjustments (that's why it has a vacuum hose from the intake manifold).

In returnless system, the regulator is too far away in the fuel tank to route a vacuum line there. So, the calibaration in the PCM now has different flow rates for different vacuum ##:

 

[Fless]

In 2004 or 2005 GM went from return to return-less system. It depends on the production year of your rig. With the reurnless system they also eliminated a fuel filter under the belly of the truck, and change fuel injector flow map.

In return system, the flow numbers are constant regardless the intake manifold vacuum, and the fuel regulator makes necessary adjustments (that's why it has a vacuum hose from the intake manifold).

In returnless system, the regulator is too far away in the fuel tank to route a vacuum line there. So, the calibaration in the PCM now has different flow rates for different vacuum ##:

View attachment 360342

This is mostly correct, with the exception of the 2004 Flex Fuel trucks. It's dependent on your model year AND if Flex Fuel or not.

From a post at ls1tech.com (https://ls1tech.com/forums/conversi...ck-fuel-pressure-regulators.html#post16979237).

"1999-2003 4.8, 5.3, 6.0 all had a fuel rail with 3/8" supply line and a 5/16" return line. The fuel pressure regulator is on the fuel rail, and has a vacuum line to the intake manifold. In 2004, All engines went to a single 3/8" supply line, with no return (returnless) except 5.3L L59 Flex Fuel vehicles. For 2004, Flex fuel engines KEPT the return line, BUT used a fuel pressure regulator with a lower pressure ratting. 2005 5.3L L59 Flex Fuel engines switched to a single 3/8" supply with NO RETURN line in 2005. Non flex fuel engines, fuel pressure spec is 55 to 62 psi with vacuum line disconnected, fuel pump running. 5.3L Flex Fuel engine 2004 and back, 48-54 psi with vacuum line disconnected, fuel pump running. 2005+ with returnless fuel rail all shared same fuel pressure spec, 55-62 psi. There is no vacuum reference on these, so fuel pressure should remain constant under all operating conditions. The computer is programmed differently for fuel flow rate depending on type of fuel rail. This is important to know when having a PCM programmed."

 

[ivin74]

During the holidays and on vacation one of neighbors is a mechanic. I had him change out the front sway bar bushings, all 4 control arms and most steering components. I used all oem GM parts. I painted all parts black prior to getting the work done. SUV rides like new now.

 

[Rocket Man]

During the holidays and on vacation one of neighbors is a mechanic. I had him change out the front sway bar bushings, all 4 control arms and most steering components. I used all oem GM parts. I painted all parts back prior to getting the work done.

Nice. Perfect timing.

 

[Rajsmoove]

I painted some panels and my doors to match my new interior. Slow process but im getting it done.

 

[ivin74]

I painted some panels and my doors to match my new interior. Slow process but im getting it done. View attachment 360420

Please post up more pictures of the interior, that new interior looks pimp!!

Did you stain the seat belts? Are you using the 03-06 second roll bucket seats?

 

[Tonyrodz]

I painted some panels and my doors to match my new interior. Slow process but im getting it done. View attachment 360420

How did you prep the plastic, and what did you use to paint/dye the interior plastics? Any prior experience with said product?

 

[mountie]

How did you prep the plastic, and what did you use to paint/dye the interior plastics? Any prior experience with said product?

One place to shop for plastic coatings is materials for motorcycle bodywork repair & paint.....

 

[Tonyrodz]

One place to shop for plastic coatings is materials for motorcycle bodywork repair & paint.....

I'm just interested in the name of the product, along with the process he used. I'd assume it was an SEM product.

 

[mountie]

probably SEM..

 

[Rocket Man]

probably SEM..

Smooth plastic is easier. You can sand it down so paint sticks easily, and then use normal automotive paint. Half of the exteriors of new cars are plastic nowadays and they use the same paint on the plastic parts as they do the metal parts. I had my bagger painted with normal automotive paint but I did have to cut and rake the fairing which required special plastic epoxies and fillers. Interior plastic is more difficult unless you sand it smooth which is a ton of work.

 

[SnowDrifter]

Got that replacement block heater. And she works!
Not sure yet how warm it gets. Letting the thing cool down and will plug it in tomorrow

 

[SnowDrifter]

Also tossed in a new t-stat on a whim. Something that's been bothering me for a while. I'd get larger temp swings than I'd like. 206 on the freeway, 214 in traffic. Stuff like that. Strictly speaking, nothing wrong.... But, killing my CDO

Put an OEM one in there and... It's rock ******* solid between 194 and 196. This isn't the first time I've had issue w/ aftermarket tstats either. Sigh.... Shoulda known to just go factory from the start

Old one (aftermarket)

Compared to OEM

 

[Teamiez]

I have noticed my OP @ about 30 at idle and just over 45 psi when rolling. My rig over 260k but the pump and timing set were done before I took ownership of it about 3 years ago

Going by the dash not a mechanical gauge I am at 40+ cold (50ish) and warmed up at idle a hair above 40. Driving I can see 60 + Depending on rpm. I had low oil pressure issues while using delco PF 46E filters, I have switched to wix 51042xp I believe they are and haven’t had a problem since. And used valvoline high mileage synthetic blend 5w30 since 100k, just flipped 200k. 3,000 mile changes.

 

[SnowDrifter]

low oil pressure should not be causing misfires or cat codes.

if its not knocking yet, op is not that low. most gm techs will tell you 6-7 psi at idle is acceptable. as long as it goes up when driving it.

then again, these trucks are known for the o ring going bad on the oil pump pick up tube to pump.

05 Tahoe LT

Just going to chime in here:
(oh god it was supposed to be a quick sentence but oops I saw a squirrel)


GM's spec for this should be thrown out the window tbh. Anything less than 20-25psi at hot idle, using the appropriate viscosity oil, is going to cause issues in not that much time. Use an oil pressure gauge, or pull the PID with a bluetooth scanner + torque. Gauge is meh.

You can cheese higher pressure by putting thicker oil in it... But that's ill advised as a fix. That's one of those things you do if you're trying to limp a couple thousand more miles out of an engine before you scrap it. Barring extremes - flow rate is more important than a static pressure.

Hell you could run diff fluid in the crank case and get 50+ psi of oil pressure. But that's going to fry your motor in short time. Why? Because the bypass valve opens, and despite higher pressure, you get less flow in the system. Which means you're at risk of not pumping enough volume to replenish the boundary layer when the engine starts spinning. It's for this reason that 'lucas' is a sham - it's just a thickener. But worse off than just using a thicker oil - regardless of what the marketing says, it's lacking on additives(dilutes your oil), and likes to make the oil foam (find their display and turn the gears for a minute you'll see what I mean). Foam in a hydraulic system is a nono.

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I replaced my oil pump a bit ago. Melling M295HV. My oil pressure at idle wasn't low. But it was fluctuating. What I found on teardown, was that my oil pump gears had light cavitation damage, and that my bypass valve had some abrasion marks at it - presumably was sticking and causing issues.

FWIW.. With that pump, some euro-spec 0w40 oil(right on the border between a thick 30w and thin 40w). My hot pressure is 47-52psi depending on various factors. I expect to get a UOA on that this year

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The o-ring can be a touch bit of a pain if you aren't paying attention. It's not difficult, but it can be a REALLY tight fit to get the thing to seat. I had to apply probably around 40lbs of pressure to the thing to get it to go 'thunk' and seat in there. If you don't feel the 'thunk' - it ain't seated. Also be mindful of different o-ring sizes / colors (youtube this one).

If you want to sanity check the o-ring: Get your engine up to full operating temp. Oil temp lags behind oil coolant temp. Coolant might come up to ~200 in 10 minutes of driving. But oil temp will take another 10 minutes beyond that. Don't rush it.

AFTER the engine is warm, park it facing downhill on the steepest spot you can find, or jack the ass-end up as high as possible. Overfill the **** out of it. Like, pour an additional 4-5 quarts in there. I don't remember what the 'critical level' is for oil to submerge the o-ring, but for the sake of a diagnostic test - the goal is to overfill it so you can get the level of oil in the crank case to cover the oil pump pickup.

Give 'er a start and note oil pressure. Don't run it like this for any length of time - the crank is going to whip up the oil and you'll probably overload your oil control rings. BUT, if you see a sharp increase in idle pressure, you've found your issue.

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Oil pressure fluctuation on my OEM pump. To reiterate: o-ring was good. The pump was just worn. Engine had ~140k on it and 4400 hours.

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Torque settings, if you want to get a digital read on your oil pressure:

 

[Fless]

If you want to sanity check the o-ring: Get your engine up to full operating temp. Oil temp lags behind oil temp. Coolant might come up to ~200 in 10 minutes of driving. But oil temp will take another 10 minutes beyond that. Don't rush it.

Slight correction: oil temp lags behind coolant temp.

 

[SnowDrifter]

LOL this flipping rig

Stepper for the coolant temp in the dash just shat out

Just.... Let me love you ffs

 

[SRQYukon]

Replaced my oil pan gasket, adjusted my front coilovers up 3/8", finished my AirLift setup with compressor and remote, replaced leaking Raybestos rear caliper that was only 4 months old. This week doing complete tune-up, trans and intake service. This past week I went to two local body & paint shops for a repaint estimate and was told that it is over a year before I can get on their schedules. It seems everyone is only interested in collision work anymore. No real repaint shops left except the classic car restoration guys and they are out two or more years.

 

[mountie]

Replaced my oil pan gasket, adjusted my front coilovers up 3/8", finished my AirLift setup with compressor and remote, replaced leaking Raybestos rear caliper that was only 4 months old. This week doing complete tune-up, trans and intake service. This past week I went to two local body & paint shops for a repaint estimate and was told that it is over a year before I can get on their schedules. It seems everyone is only interested in collision work anymore. No real repaint shops left except the classic car restoration guys and they are out two or more years.

A complete paint job.... Have you considered a boat paint shop? They are as good & very capable.
Maybe they have a better time frame?