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What did you do with your GMT400 today...or yesterday....

I read those will destroy the sensor upon removal, not sure I could install an new one with that tool. What say you?
I would say installation with that tool would be tough.

I'm guessing that installation would involve installing a T in the mix.

I believe there's 2 ports by the oil filter location.

When I did my first engine oil bypass filters, I used a port near the engine oil cooler lines.

I believe it was a 5/16 square female plug. 5/16 square male on the socket to get it out. I remember making a socket with a piece of key stock.

Still have it in my tool box
 
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I would say installation with that tool would be tough.

I'm guessing that installation would involve installing a T in the mix
Yeah I’ll check if I have a spare 1 1/16” 6 point socket I can cut up and modify instead, just gotta get the wood stove fired up in the shop. Took the day off to try and get this sorted out.
 
If it all goes well I’ll just borrow the fuel pressure gauge setup I put on the Ram; grease gun hose, gauge, and snubber valve (though the valve is unnecessary in this application) and T the pressure sensor off of the grease gun hose in a better, more accessible location. Will probably have to ground the sensor somewhere too...
 
Been away for a while folks, but now I’ve got a question.

On my 6.5, how do I check the ACTUAL oil pressure? I have no idea if my dash gauge is feeding me BS or if the oil pressure really is fluctuating wildly...
I fear damage may already have been done if the pressure is actually bad as it sat idling for a while before I saw what it was doing 😬
3 ports- behind driver side head coming out if the block next in line is the one in the middle of the valley where ops is hooked up. Last one is at the end of the oil circuit and therefore the lowest oil pressure location of the engine- where the turbo gets fed from the passenger front.

Pick your poison location and put in a mechanical gauge.

Engine At operation temperature, idle oil pressure needs 8psi.
 
Yeah I’ll check if I have a spare 1 1/16” 6 point socket I can cut up and modify instead, just gotta get the wood stove fired up in the shop. Took the day off to try and get this sorted out.
You'll need a 12 point socket. if there is an auto parts store nearby you'd be better and faster to run down there and snag up on the special socket. their price isn't too bad. even if there is a harbor freight or one of those cheap Chinese tool stores .
 
3 ports- behind driver side head coming out if the block next in line is the one in the middle of the valley where ops is hooked up. Last one is at the end of the oil circuit and therefore the lowest oil pressure location of the engine- where the turbo gets fed from the passenger front.

Pick your poison location and put in a mechanical gauge.

Engine At operation temperature, idle oil pressure needs 8psi.
8 psi! I get worried when my gauge goes under 25 on the dash! LOL

while on the subject of oil pressure for these engines. when you have a high mileage engine that still runs fine yet pressure might be suffering or not staying consistent as it might have once did during it's younger years, is there simple things one can do to increase the pressures giving a little more longevity into it?

this thought had come to me a while back and thinking about it again, if a person didn't want to touch the crank or cam but just swap in a high-volume pump or mod the pressure of the existing pump, would that increase pressures and not harm anything? an example is if you see a max of 25 idle and 40 at 2k + rpm and want to see it push 60 or so. just not so much it blows seals and what not.

I myself don't have too low of a pressure right now, but this has always been a curiosity of mine for if I was to ever pull the engine doing other things like replacing all gaskets and seals to stop leaks. I figured if I did this, might as well do the oil pump while it's accessible too.
 
8 psi! I get worried when my gauge goes under 25 on the dash! LOL

while on the subject of oil pressure for these engines. when you have a high mileage engine that still runs fine yet pressure might be suffering or not staying consistent as it might have once did during it's younger years, is there simple things one can do to increase the pressures giving a little more longevity into it?

this thought had come to me a while back and thinking about it again, if a person didn't want to touch the crank or cam but just swap in a high-volume pump or mod the pressure of the existing pump, would that increase pressures and not harm anything? an example is if you see a max of 25 idle and 40 at 2k + rpm and want to see it push 60 or so. just not so much it blows seals and what not.

I myself don't have too low of a pressure right now, but this has always been a curiosity of mine for if I was to ever pull the engine doing other things like replacing all gaskets and seals to stop leaks. I figured if I did this, might as well do the oil pump while it's accessible too.
Just my observation. But it seemed to me that engines run on full synthetic lasted longer and carried better oil pressure in their later, higher mileage years
 
I have settled and used the rotella 5-40 T6 for the last few oil changes. I was hooked on mobil 1 but I can't ever find it anymore, so I went with Rotella. I use the same T6 formula in the Jetta too for the high zinc content. :happy:
 
Yeah it’s kinda tight by the fuel filter, I shoulda relocated that years ago. There’s also too much grime by the oil filter to see any other ports in that location. Oh well I think I can cobble something together to get at the OPS with an old socket, possibilities are endless when you have a welder 👍🏼😁
Pull the manifold. Not that bad a job. While in there, clean up the valley, install new diesel rated fuel hoses to and from the IP and the FFM and an extension hose for the OPS.
Go to leroydiesel.com he has a real nice remote hose for the OPS already made up and the price is cheaper than the 1/4” hydraulic hose I had made up at NAPA.
 
@J_dude if your climate allows (doesn't get cold enough to need a fuel heater) you can do the remote mount fuel filter on the firewall and eliminate the FFM completely. when I pulled my intake to address the old fuel lines and do my valve cover gaskets, I installed this fuel filter on the firewall up by the trans dipstick tube. ran my fuel hoses over the top of the intake so they weren't down under there in the heat of the engine valley and are easy to get to in the event a leak happens. Plus the added benefit of easy access to the OPS too!

 
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I will try to post up a pic of how I have mine mounted. the down side is I don't have the sensor anymore that lights up the WIF light. (water in fuel) but it's easy to open the power barn to have a looksee every once in a while :happy:

the clear bowl does have a threaded provision to install a universal WIF sensor if you would like to keep the dash warning light.
 
Nick got his ladder rack welded how he wants it. He wiped it down with mineral spirits. He started hitting it with the shake and shoot spray paint. I seen some areas the MS had not dried, stopped him, give it a shot of B&P cleaner. That dried it mighty fast. Got it painted.
He took off for a doc appt, i went snow cleanup, waiting for his return to load it back onto his service truck.:
Then the K3500’ll be back into duh garage and some more dismantle time on it.
 
You'll need a 12 point socket.
Wanna bet? Lol 5700C478-53A3-491D-A680-DC23B635F120.jpeg
Everything I read says 12 point will just round it off anyway.

Pull the manifold. Not that bad a job. While in there, clean up the valley, install new diesel rated fuel hoses to and from the IP and the FFM and an extension hose for the OPS.
Go to leroydiesel.com he has a real nice remote hose for the OPS already made up and the price is cheaper than the 1/4” hydraulic hose I had made up at NAPA.
Too late! Already built my “special tool”. Don’t look at my welds! 🙈

Just waiting for the thread sealer to cure and then the hose and gauge setup is going in, had to run to town and grab a couple fittings though.
61C98F6F-03FC-419E-B154-0E63CC728045.jpeg
 
8psi is their low spec- mind you they had to pick a level that if it were below that under warranty- then they were responsible for repairs. I am amazed it is not 1psi. Haha.

Under 20 I get worried btw.

So say you have low pressure and want to see what to do.

You could remove the drain hose from turbo and monitor the volume of oil coming out. But without something to compare it to- is what you see enough? Here is the thing- if you have bad flow, thicker oil will make it worse, if great flow then thicker oil can help.replacing 1 pint of 40 wt with 80/90 does wonders for tire old engines in the desert. I’ve known more than one rig to run 1 quart 80/90 wt. this doesn’t help the oil going through the lifters, but can help everywhere else if normal bearing wear is the problem.

Remember pressure is just the resistance to flow. N/A engines saw higher psi do to no open feed line to turbo.

You can always buy a new oil pump. Before installing, do some tricky tricky like shimming the spring for more pressure. Clean up and clearance the pump internals for optimal oiling.

I am still waiting to see some custom pumps made- taller gears, longer spafer and longer bolts. We know the difference of standard pump to high volume pump.
If you keep the pressure spring the same but taller gears= more volume same pressure.

Always replace that stupid plastic drive connector and please someone get some metal ones made before I put this engine together. I have never understood why thats plastic. Pump grinds to a stop from debris and you are worried to save the camshaft teeth or something? Engine is toast already. VS plastic connector breaks because…PLASTIC, and oil pump stops. SMH. Ok, train back on track….

Engine Restore oil treatment in a can ACTUALLY WORKS. Been tested three ways from Sunday by multiple outfits including US Military- and zero drawbacks. Its even same cost by volume as any mid level oil. So not like its expensive.

Remember oil loss is cumulative. So if you have the pan off and want to slip in bearings from underneath- that is how big boy diesels are done- we call it an inframe.
 
I just eliminated everything the factory put on the truck for a fuel system. Pressure gauge is pegged because I didn't have it hooked the the regulator yet. It idles at 7psi.
 

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@Will L. I was thinking in the terms of a higher volume pump when oil is slipping out of worn bearings and other crevices due to a a tired worn enging that it might push that extra amount having more oil going up into the valve train and turbo also creating slightly more pressure because it's pushing more. not more pressure than it's supposed to but closer to what it was when the tired engine wasn't so tired. lol..

for me, I'm actually a chicken to attempt removing main and rod caps to stick in new bearings on these engines due to the web cracks that form. on top of if the journals have uneven wear or ridges from that, a new bearing might cause more issues than just leaving them alone and let it ride till it can't no more... 🏇🏇
 
Ok boys, I have good news!
We’ve got a steady 40psi on the mechanical gauge at idle!

The bad news is, I shoulda called GM this morning, now I won’t be able to get the new sensor till Monday. Oh well, if that’s the worst news out of this situation we’re doing pretty well I’d say!
That's awesome news. try looking on amazon for the delco part number. you might be able to have it delivered overnight. and SOME auto parts... not many carry Delco parts
 
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