I have been running 5 qts m1 10w30 and 1 qt lucas hd oil stabilizer in a 6.0 lq4 engine that has some lower oil pressure in hot weather. What would my actual viscosity resemble with this mix? I plan to switch to a 5w40 syn or 40wt euro syn most likley mobil or pennzoil. I am averaging 15 psi hot at idle and as low as 12 on straight 10w30 syn in 75+ temps. With the lucas it stays 18-23. Cruising 60-70 it stays 35-40 psi no matter what i pour in.
M1 lucas mix
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I wouldn't consider 12 psi at idle low. Especially if it's 35-40 while cruising.
Originally Posted by Skippy722
I wouldn't consider 12 psi at idle low. Especially if it's 35-40 while cruising.
+1 Try a 5w-40 or 10w40 HDEO oil and ditch the Lucas.
I wouldn't consider 12 psi at idle low. Especially if it's 35-40 while cruising.
+1 Try a 5w-40 or 10w40 HDEO oil and ditch the Lucas.
You should ask that question before you put lucas in. It has a cSt of 110, so add the visc of m1 times the quarts you put in, say 7 total quarts one qrt being lucas. (6 x 10) + (1x110) = 170 then divide by 7, you starting operating viscosity would be around 24 until that lucas sheared down, and it would. Basically you are running 140w gear oil in your engine, that has a cSt of 26.
You can probbaly solve the problem with a new oil pump, although I do realize sometimes that requires taking everything off the front end. Not sure about your application or year or mileage. If you are towards the end of the life of the vehicle maybe adding lucas has it's purpose, but 95% of the time I say leave that stuff alone.
Originally Posted by Spitter
I have been running 5 qts m1 10w30 and 1 qt lucas hd oil stabilizer....
Oh God why? Just put lard in your engine, it's cheaper at least and not much worse...
I have been running 5 qts m1 10w30 and 1 qt lucas hd oil stabilizer....
Oh God why? Just put lard in your engine, it's cheaper at least and not much worse...
Originally Posted by Spitter
I have been running 5 qts m1 10w30 and 1 qt lucas hd oil stabilizer in a 6.0 lq4 engine that has some lower oil pressure in hot weather. What would my actual viscosity resemble with this mix? I plan to switch to a 5w40 syn or 40wt euro syn most likley mobil or pennzoil. I am averaging 15 psi hot at idle and as low as 12 on straight 10w30 syn in 75+ temps. With the lucas it stays 18-23. Cruising 60-70 it stays 35-40 psi no matter what i pour in.
The Lucas Oil Stabilizer is doing far more harm than a few psi lower oil pressure.
I have been running 5 qts m1 10w30 and 1 qt lucas hd oil stabilizer in a 6.0 lq4 engine that has some lower oil pressure in hot weather. What would my actual viscosity resemble with this mix? I plan to switch to a 5w40 syn or 40wt euro syn most likley mobil or pennzoil. I am averaging 15 psi hot at idle and as low as 12 on straight 10w30 syn in 75+ temps. With the lucas it stays 18-23. Cruising 60-70 it stays 35-40 psi no matter what i pour in.
The Lucas Oil Stabilizer is doing far more harm than a few psi lower oil pressure.
Add 15w50 Mobil 1 , not crap Lucas oil stabilizer.
I would use filtered bacon grease before I put that molasses in my engine. If you need higher viscosity because of burning or a leak, go up a grade or two. In the op scenario I would use 10w-40 hdeo. As others have posted.
Although I'm not going to jump the Lucas bash train, I like this suggestion. Also keep in mind you could have a malfunctioning oil pressure sensor or even a bad gauge. All too common regular problem on GM's. If you were to have a weak oil pump, as long as the trucks a two wheel drive oil pump replacement isn't too bad of a job. Four wheel drive, you'd be pulling the engine out or the front diff out so you could pull the pan. I'd pull the diff.
Maybe verify the oil pressure is correct. If so, I would try some 15W40.
There is a ton of info on the oil pressure issues on these engines including the O ring issue Linctex mentioned and the oil pressure sensor issue. I found going from 5w30 to 5w40 gave me a few psi at cruising speed. Keep in mind it is controlled with a valve to stay at around 40 psi at cruise speed.
Many MILLIONS of bottles of Lucas are sold and used every year and no harm comes from it... it isn't an ideal additive and doesn't do much but thicken your oil- but don't let these fear mongers scare you, it isn't going to hurt your high mileage truck at all.
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The minimum oil pressure specs that I have for the LQ9 are:
6psi @ 1k rpm
18psi @ 2k rpm
24psi @ 4k rpm
Per these . . . it sounds like you are okay.
on P. 17 . . .
https://www.bakesonline.com/images/MediaLibrary/Indmar_6.0LQ9RepairSpecs.pdf
6psi @ 1k rpm
18psi @ 2k rpm
24psi @ 4k rpm
Per these . . . it sounds like you are okay.
on P. 17 . . .
https://www.bakesonline.com/images/MediaLibrary/Indmar_6.0LQ9RepairSpecs.pdf
Okay, it won't hurt him, but what will it gain him? If you feel your oil isn't thick enough, buy thicker oil. They're all over the shelves.
Originally Posted by Garak
Okay, it won't hurt him, but what will it gain him? If you feel your oil isn't thick enough, buy thicker oil. They're all over the shelves.
Plus the thicker oil will have additives in it where the Lucas Oil Stabilizer has pretty much none.
Lucas Virgin
TBN - 0.1
Visc - 615.3
FP - 435
Calcium - 3
Magnesium - 1
Phosphorus - 4
Zinc - 2
(taken from this thread https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/890170/1 )
Okay, it won't hurt him, but what will it gain him? If you feel your oil isn't thick enough, buy thicker oil. They're all over the shelves.
Plus the thicker oil will have additives in it where the Lucas Oil Stabilizer has pretty much none.
Lucas Virgin
TBN - 0.1
Visc - 615.3
FP - 435
Calcium - 3
Magnesium - 1
Phosphorus - 4
Zinc - 2
(taken from this thread https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/890170/1 )
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