Possible sludged VQ37HR

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165
Location
Tn
My father recently bought a G37 at an auction. 2011, 30k. I pulled the dipstick, and it was low about .75qt. The oil was very black, and had a chunk of black gook on it! My heart sank a little, but I added a quart and am trying to figure how bad it could be. I put a flashlight down the oil fill hole, and things looked relatively clean. The engine idles quietly, and it doesn't smoke. Before you say "RETURN IT," he can't - it was an auction. What oil should I run in this thing? I was thinking Rotella T6 0w40, but maybe this is overkill. How about Mobil 5w30 Syn? Must this engine use synthetic? I did a search but 'g37' doesn't qualify as a search term.
 
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6,170
Location
North Coast
I would try a few runs of PP with 5000 OCI and cut open the filter afterwards and see what you get. Reevaluate at 50k
 
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Messages
163
Location
Tennessee
I would do several short oci on it. My oil choice would be a hedo oil like rotella t-5 or t-6..for the good cleaning action of a hedo. Filter choice would be a cheap 1, then as I worked the oci longer out I would change to a better quality filter. Keep this in mind.. what ever you do. Do it slow.. no cleaners engine flushes etc. You do not want a big chunk of sludge etc to restrict the oil p/u. Start with 500-1000 mile oci and work up from there.
 
Messages
427
Location
SC
I am a MMO advocate. My family has used it for generations (see thread in progress in the oil additives sections) It is an effective, yet gentle cleaner. No it wont hurt the engine. Use 20% mmo, 80% engine oil with a new filter. If you want to be extra careful, make it a very short first OCI 1,000-1,500 miles. (use a cheap oil and filter) Id then run it for 3,000-5,000 miles as written above for a few additional changes before switching to a quality Synthetic. oh, and check that PCV valve too
 
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Messages
2,777
Location
NYC
I'd run a few 3K runs with PP Do your standard used car checklist, give the other easy fluids a once over. Go to a Nissan dealer, ask for an ASIST report while there checking for open recalls, just to make sure.
 
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25,974
Location
MA, Mittelfranken.de
Originally Posted By: aualtima3.5
I put a flashlight down the oil fill hole, and things looked relatively clean.
The oil filter on these is tiny. They seem to do better on Mobil 1 0w40 when they have slight consumption issues, this oil also has good cleaning abilities. I would only use synthetics in these engines. Change the PCV and make sure the PCV hose connecting the left and right banks at front of the engine is clear IIRC you need to pop the upper plenum. Fill with Mobil 1 0w40 and change the filter, change the filter again at 1K and do 3K OCI for a couple of changes. It should clean up fine with no additional additives.
 
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524
Location
sc/fl
Several short (3k) OCI's with a good synthetic. T6 or M1 0-40 would be my first choices. Change the oil filter after the first 1k miles and if you're so inclined cut it open and inspect. It will give you an idea if it really is sludged. Under no circumstances should you do an engine flush, they do more harm than good.
 
Messages
427
Location
SC
Originally Posted By: 29662
Several short (3k) OCI's with a good synthetic. T6 or M1 0-40 would be my first choices. Change the oil filter after the first 1k miles and if you're so inclined cut it open and inspect. It will give you an idea if it really is sludged. Under no circumstances should you do an engine flush, they do more harm than good.
MMO is not a "flush"
 
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2,391
Location
Paradise of Florida
Change the oil/filter now. Change it more often and more frequently then needed. Use a full synth oil. Change the oil at 1k, 2k, 3k... working your way up to a full 5k or 7.5k interval. Don't use ANY solvent, ester, or detergent additives until you have performed 3-4 OCI's. Don't want to falsely blame a product for any issues caused by lack of maintenance. Warranty without proof of maintenance... good luck. Any full synth 0w30, 5w30, 10w30, 0w40, or 5w40 will work fine. Change the diff, psf, transmission fluid, brake bleed, antifreeze, engine/cabin air filters, and run a couple bottles of FI cleaners. Don't fret over a little sludge. Maintenance will clean it up.
 
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1,800
Location
Rijeka, EU
I would change oil with M1 0w-40 and good quality synthetic media oil filter. Best would be OEM. OCI no less than 10k miles with this setup. To ease your mind i bought a new Fiat CR diesel, made oil change on 3k km by myself, then got it remapped to 160 hp (stock 120). Next oil changes where all 30 k km (per book) with no issues now with 160 k.
 
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3,048
I would PYB a few short OCI's. My first would be 2k miles with 12oz or so MMO for the last 500-1k miles. Then build it up to PYB 3k and and 5k and UOA to see what you've got. But that is just what I would do. I feel comfortable with the initial shorty so to speak, just in case you loosen up some larger deposits. That is pretty much what I did with my Camry.
 

aualtima3.5

Thread starter
Messages
165
Location
Tn
Originally Posted By: chrisri
I would change oil with M1 0w-40 and good quality synthetic media oil filter. Best would be OEM. OCI no less than 10k miles with this setup. To ease your mind i bought a new Fiat CR diesel, made oil change on 3k km by myself, then got it remapped to 160 hp (stock 120). Next oil changes where all 30 k km (per book) with no issues now with 160 k.
I am seeing a lot of 0w40 M1 recommendations. Is this okay to run for a car that specs 0w40 and is under warranty (questionably under warranty...). The t6 interests me as well, but these are kinda thick oils. I have used 0w40 in my VQ35 Altima with no ill effects, but it was my car/out of warranty. This is my dad's car and I don't want to ruin his first "fun" car.
 
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3,566
Location
Somewhere
Originally Posted By: dave1251
The factory warranty should still be intact. I would just use PYB 5W30.
This. Power train is out to 75k and keep it changed and maybe use the dealer. If it breaks, let them fix it.
 
Messages
1,800
Location
Rijeka, EU
M1 0w-40 isn't really thick oil, is it. Car with 30k DO NOT have sludge in engine. I wrote before about my 30k OCI just to show you 30k is nothing, 0.5L low on oil is nothing. But i did read somewhere that Nissan recommend even Ester oil so dino is no go for this car.
 
Messages
28,123
Location
Regina, Saskatchewan, Canada
Originally Posted By: chrisri
But i did read somewhere that Nissan recommend even Ester oil so dino is no go for this car.
Dino is perfectly acceptable in this vehicle. All it will call for is 5w-30 in SM/GF-4 or newer. There might still be some significant warranty remaining on this vehicle, so my first consideration would be some short OCIs with PYB 5w-30 and no flushes or additives. Of course, I'm obviously not afraid of running a 40 grade in such a vehicle, considering I'm running Delvac 1 ESP 5w-40 in mine.
 
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