Engine noise after oil change?
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I hear even Rotella is dropping zinc levels and is Rotella capable of going 10-12k on a oil change? That is my whole reason of using Mobil1 EP is for extended oil changes, my kid is driving back and forth to work and school and has very little time for maintenance and is racking up a lot of miles, we figure about 25k a year and I would like to practice two oil changes a year on his truck.
Rotella is not dropping zinc levels. There was a change from CI to CJ. CI spec used to be about 1400/1500 ppm where the CJ spec is about 1200ppm. I cant tell you to go 10-12K on it but i can almost definitely say that if M1 extended can, then i would put money that the 5w40 would do the same.
Originally Posted By: Radman
Change the oil filter. It may be defective. If not then the previous owner put in a heavy weight oil or motor honey to quiet it out.
That was my first thought...nice, fresh looking Valvoline 60 wt VR1...to keep the rod knocking noises down for the sale...
Change the oil filter. It may be defective. If not then the previous owner put in a heavy weight oil or motor honey to quiet it out.
That was my first thought...nice, fresh looking Valvoline 60 wt VR1...to keep the rod knocking noises down for the sale...
Originally Posted By: disturban
Do you guys think all the engine noise I am hearing could be because the Mobil 1 EP is a SN rated oil and does not have as much ZDDP as older oils and the 1995 4.0 is a flat tappet camshaft?
I think am going to add some Redline Engine Oil Break-In Additive to boost the ZDDP level and hope that will quiet things down?
ZDDP or any other additive won't quiet it down, they're good for wear, sure, but noise happens because of excessive bearing clearance, so increased viscosity might help.
What's your oil pressure at warm idle? If it's really low, like under 8 PSI, then your oil is too thin for this set of bearings.
If you really think it's a rod knock, then the motor is on its last legs (yeah, you can change rod bearings, even mains, but that's a stopgap measure at best because you're not able to mic the journals and know if they're worn or not). But lots of things can sound like a knock...
I would change the oil and filter ASAP, start with an HDEO like Rotella T 15W40 or the T6 if you're a synnthetic guy...see what happens to the noise then.
Do you guys think all the engine noise I am hearing could be because the Mobil 1 EP is a SN rated oil and does not have as much ZDDP as older oils and the 1995 4.0 is a flat tappet camshaft?
I think am going to add some Redline Engine Oil Break-In Additive to boost the ZDDP level and hope that will quiet things down?
ZDDP or any other additive won't quiet it down, they're good for wear, sure, but noise happens because of excessive bearing clearance, so increased viscosity might help.
What's your oil pressure at warm idle? If it's really low, like under 8 PSI, then your oil is too thin for this set of bearings.
If you really think it's a rod knock, then the motor is on its last legs (yeah, you can change rod bearings, even mains, but that's a stopgap measure at best because you're not able to mic the journals and know if they're worn or not). But lots of things can sound like a knock...
I would change the oil and filter ASAP, start with an HDEO like Rotella T 15W40 or the T6 if you're a synnthetic guy...see what happens to the noise then.
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The noise is gone, I would not say it was one rod knocking it sounded like all of them knocking, but I added Redline break in oil and it all went away...I have to blame it on low zinc in SN rated oil, there is just no other explanation, the redline did not turn my 30wt Mobil1 into a 40wt.
Oil pressure was 30lbs at idle when we bought this jeep and it is at 30lbs after we changed to the Mobil1 EP, oil pressure is great and has not changed, I should have asked the previous owner what oil he used but the thought never crossed my mind.
I did however check the oil before we bought it and it was just changed and right at the full mark and did not appear to be thick, the guy seemed to be pretty straight forward and told me the motor uses no oil between changes and he did not lie about that, we drove it for 5k on the oil that was in it when bought it and it stayed right on the full mark. So judging by his honesty and examining the oil by touch before I bought it I would have to rule out motor honey.
I will give Rotella 5w40 a shot next time we change it and see what happens and send in a sample to Blackstone at about 7k and see where we stand.
Oil pressure was 30lbs at idle when we bought this jeep and it is at 30lbs after we changed to the Mobil1 EP, oil pressure is great and has not changed, I should have asked the previous owner what oil he used but the thought never crossed my mind.
I did however check the oil before we bought it and it was just changed and right at the full mark and did not appear to be thick, the guy seemed to be pretty straight forward and told me the motor uses no oil between changes and he did not lie about that, we drove it for 5k on the oil that was in it when bought it and it stayed right on the full mark. So judging by his honesty and examining the oil by touch before I bought it I would have to rule out motor honey.
I will give Rotella 5w40 a shot next time we change it and see what happens and send in a sample to Blackstone at about 7k and see where we stand.
That's great news! I am always happy to hear of someone's success in resolving a problem.
Not what I expected for an outcome, but the good pressure at idle is a good sign of a healthy motor..enjoy the new truck!
Not what I expected for an outcome, but the good pressure at idle is a good sign of a healthy motor..enjoy the new truck!
Yes, I'd like to see how T6 performs in this app. It has a good TBN and should last at least 7,500 compared to the 30 multi-grade oils you mentioned, if extended OCI length is a goal. Still, it's generally best to stay within spec and that would be a thicker setup that what you have. Instead of the break-in additive I believe STP makes a good shot of ZDDP that isn't just motor honey etc, so you could try that on top of an EP oil next time like AZO if you did return to that route.
Additive levels are the exact same between SM and SN oils, so no, SN oils AREN'T the problem here!
The problem is the thickness of the oil - the Redline additive you added thickened up the oil somewhat, and quieted the motor.
T6 going forward is an excellent plan, BTW.
The problem is the thickness of the oil - the Redline additive you added thickened up the oil somewhat, and quieted the motor.
T6 going forward is an excellent plan, BTW.
Originally Posted By: addyguy
Additive levels are the exact same between SM and SN oils, so no, SN oils AREN'T the problem here!
The problem is the thickness of the oil - the Redline additive you added thickened up the oil somewhat, and quieted the motor.
T6 going forward is an excellent plan, BTW.
I'll mostly agree with that.
I believe (who knows, maybe I'm wrong) that in they are the same in terms of wear protection, but formulated to yield better fuel economy and tolerate longer drain intervals. I know there was a chart comparing and contrasting SM/SN oils somewhere around here.
At any rate, you pretty much beat me to the punch...
Additive levels are the exact same between SM and SN oils, so no, SN oils AREN'T the problem here!
The problem is the thickness of the oil - the Redline additive you added thickened up the oil somewhat, and quieted the motor.
T6 going forward is an excellent plan, BTW.
I'll mostly agree with that.
I believe (who knows, maybe I'm wrong) that in they are the same in terms of wear protection, but formulated to yield better fuel economy and tolerate longer drain intervals. I know there was a chart comparing and contrasting SM/SN oils somewhere around here.
At any rate, you pretty much beat me to the punch...
Originally Posted By: disturban
The noise is gone, I would not say it was one rod knocking it sounded like all of them knocking, but I added Redline break in oil and it all went away...I have to blame it on low zinc in SN rated oil, there is just no other explanation, the redline did not turn my 30wt Mobil1 into a 40wt.
How much ZDDP in that Redline break in oil? Where did you buy one? Is it dino or ester based?
The noise is gone, I would not say it was one rod knocking it sounded like all of them knocking, but I added Redline break in oil and it all went away...I have to blame it on low zinc in SN rated oil, there is just no other explanation, the redline did not turn my 30wt Mobil1 into a 40wt.
How much ZDDP in that Redline break in oil? Where did you buy one? Is it dino or ester based?
Originally Posted By: friendly_jacek
Originally Posted By: disturban
The noise is gone, I would not say it was one rod knocking it sounded like all of them knocking, but I added Redline break in oil and it all went away...I have to blame it on low zinc in SN rated oil, there is just no other explanation, the redline did not turn my 30wt Mobil1 into a 40wt.
How much ZDDP in that Redline break in oil? Where did you buy one? Is it dino or ester based?
red line break in oil additive:
phos.17,000ppm
zinc 20,500ppm
cal.16,950ppm
silicon 158ppm
moly 15ppm
boron 5ppm
I only used about 6 ounces of it so I doubt it thickened the oil any, it just added zinc and other additives.
Bought it online!
Originally Posted By: disturban
The noise is gone, I would not say it was one rod knocking it sounded like all of them knocking, but I added Redline break in oil and it all went away...I have to blame it on low zinc in SN rated oil, there is just no other explanation, the redline did not turn my 30wt Mobil1 into a 40wt.
How much ZDDP in that Redline break in oil? Where did you buy one? Is it dino or ester based?
red line break in oil additive:
phos.17,000ppm
zinc 20,500ppm
cal.16,950ppm
silicon 158ppm
moly 15ppm
boron 5ppm
I only used about 6 ounces of it so I doubt it thickened the oil any, it just added zinc and other additives.
Bought it online!
OMG!
SLOB (that I use for my boat only now) is nothing compared to this stuff.
SLOB (that I use for my boat only now) is nothing compared to this stuff.
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