DOD delete low oil pressure beat!

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Coolman1987us

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I have a 2011 Tahoe SSV 4x4 5.3l/6L80e with enhanced cooling package, , electric fans, factory lift, louvered hood, chrome spotlight, front and transmission skid plates. I just changed the stereo with a 10" Android touchscreen with a hardwire backup camera and GPS. I changed the steering wheel position sensor and got Stabilitrack working. I took apart my guage cluster to replace the oil pressure stepping motor- ordered the wrong one from Amazon- wasnt the problem anyway. I opened the dash again to fix the rattle. Changed all the window regulators. Changed headlamps.

My transmission went out at 155,000mi. I had it rebuilt by others and added a TruCool tranny fluid cooler in series with the new enhanced cooling package radiator (9 ports) that I had just put in a month before. He hit my AC cooler with a sawzall while installing the TruCool and replced it. Charged the AC. Now it has a new front cooling stack. Transmission cooler, AC cooler, and radiator. Nice. A month later a lifter went out. .



I installed all new;

valley cover, LS1 lifters, lifter trays, LS1single bolt camshft(California smog sucks), removed VVT, timing chain, chain tensioner, timing gears, LS1 timing cover, oil pan filter bypass delete(I had to remove the front differential 2 times because I forgot to add the bolt the first time I had the pan off when changing the oil pump- good times), oil tower steel plugs, one time use bolts include camshaft- harmonic balancer- head bolts- exhaust bolts, spark plugs, wires, replaced driver side valve cover with the Pressure Control Valve, added an oil catch can from PCV to intake plenum, added Rough Country cold air intake and use a oven range filter for the bottom hole under the filter box(air gets sucked in from the louvered fender hole only), added Rough Country 1.5" alluminum under spring leveling kit.

I did it all myself and by myself. ASAP on weekends from early morning until flashlight. I had a helper on the jack for the front differential. All of the rebuild was done with the engine in the truck in my backyard during rainy season and I was still in bad shape from a rescent back injury. I tore a muscle in my left shoulder and had to go to the E.R. Exhaust still assembled. Do yourself a favor and seperate the exhaust. But hold on.

I had a severe low oil pressure that would cuase shut down warning. I feathered brake and gas. I knew it needed a higher idle speed. I could not find a mechanical idle adjustment. I guage tested oil pressure via driver side block heater port. There was higher pressure there being near the oil pump. I read the bolt specs and found the oil pressure sending unit was the same size. I cut the harness and extended it from the valley to the block heater port. Drivable at that point but oil pressure still about 8psi at idle and a bit shakey. I changed the oil with 20-w50. Oil pressure at 12psi. Very drivable and sluggish, heavy feeling but solidish.

Then I found HPtuners MPVI3. Earlier I had AFM and VVT programmed out by mail. I hooked the truck up to the laptop with HPtuners. I found my idle speed was set at 525rpm at idle from factory. I raised the idle to 625rpm and changed my oil back to 5w-30. I raised my in gear idle speed to match my idle in park. Oil pressure is now 22 to oil pump bypass at 75psi. I made my throttle more responsive.

My truck drives better than it ever has. It can breathe and it doesnt have oil dripping in past the PCV to burn and corrode the valves with the oil catch can in place. Gas milage is the same but I gun it more to hear it now so I dont know. Tows the 28' trailer better than ever. It tows without a hitch! Ha!

8 cilindars all the time like God intended.



Any questions?
 

Marky Dissod

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Don't know anyone who can command V4 mode at will or whim.
However there are 'Enable Thresholds', coolant temp, engine speed, road speed, and throttle being the most relevant.

Back when I was a livery driver / chauffeur in NY / NJ / PA / CT, I figured, since I was NOT keeping 'my' GMC YXL beyond the initial lease,
I tried to INCREASE the V4 mode duty cycle during lazy 'Miss Daisy' driving, to try to increase MpGs, specifically in New York City.
It was worth a SMALL net city MpG improvement, and a SMALLER net highway MpG improvement.
I changed my oil every 2500-3000 miles, and experienced no signs of lifter issues.
BUT!
Oil consumption increased after about two years of 'more V4 mode' than most of you that just left it enabled.
Though unproven, piston ring coking seems the most likely culprit,
because the lazy cylinders quickly cool off compared to the fulltime cylinders.
(Early Hemis with V4 mode let the lazy cylinders cool off for far too long, enough to crack engine blocks.)

Based on my considerable experience with (more) Engine Half@$$,
the only defensible use of V4 mode, would be to delay or mitigate overheating, by raising the
'V4 Mode Coolant Temp Enable Threshold' to somewhere between 221F / 105C - 230F / 110C
This would disable it during normal driving, and even most considerably enthusiastic driving.
It would only allow V4 mode if the engine is hot enough that the owner / driver should be concerned.

Either the coolant temp comes back down, and V4 mode is no longer allowed, OR
IF the coolant temp does not come down, the driver is warned sooner than GM would warn,
giving additional time to avoid overheating.

Under nearly all NORMAL circumstances, it would be disabled. Most sensible owners would never experience it.
It'd only go V4 if it got too hot.

That's my idea, anyway ...
 
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Dod5-3-6L80e

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Tuned the ECM/ECU using HpTuners MPVI3 and my laptop computer.
 

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Dod5-3-6L80e

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what auction did you get it from? I too have a BP Tahoe that I got from a dealer in National City, and it was stationed in Calexico.
As I was flipping cars I would buy at auction I met a liscensed dealer that got 4 Tahoes and 1 Suburban from a San Diego government auction. He may storefront in National City. Hes got a fenced in gravel lot. Believe his name is Dave.
 

mikez71

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Tuned the ECM/ECU using HpTuners MPVI3 and my laptop computer.
How do you tune that??? And what was it doing before tuning?
And what year 5.3? Your stock values look different than mine.

I keep hearing about people tuning their VVE or running speed density.
I think I'm too scared and lazy to do that.. unless it's sooo much better?
 
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Dod5-3-6L80e

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How do you tune that??? And what was it doing before tuning?

I keep hearing about people tuning their VVE or running speed density.
I think I'm too scared and lazy to do that.. unless it's sooo much better?
Diablo tuners would not do what I needed most, adjust idle, so I got HPtuners MPVI3. It allows you to adjust spark timing, throttle response, transmission shift points, air intake, - name it. Im still blown away with what it allows you to tune. You can make a regular engine into a different animal. Highly reccomend.
 

mikez71

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Sure is fun (and overwhelming!) looking at all the tables and variables.

I have been working on a transmission tune, and I'm quite happy with it just for daily driving compared to stock.
Mostly shift scheduling, I highly recommend the 2015 shift schedule as a starting point.
..currently trying to figure out what 'desired output torque factor' does..

But how do you determine how to tune the throttle follower?
Are you logging airflow/throttle position/torque output or something, or is it by feel?
And, why is 3rd gear so different from the rest? (which looks like you tweaked to be inline with the other gears)
 
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