Over the years I have heard many rumors about Pennzoil and Quaker State causing sludge in engines. Today I read about Castrol causing the same problem. It seems the only major brands I never hear of any sludge problems with are Mobil and Valvoline. What are your guys opinions and real-world experience. I have heard that Valvoline has a very different add pack than other oils, could this contribute to less sludge in engines?
Sludge rumors
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Triple_Se7en
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Pennzoil is the #1 seller on earth. If it was a sludge monster, it wouldn't be in the top-5.
Sludge is mostly the fault of poor engine design, followed by overextended oil changes - then engines that either work too hot, or contains oil contaminated with either fuel or coolant dilution.
Sludge is mostly the fault of poor engine design, followed by overextended oil changes - then engines that either work too hot, or contains oil contaminated with either fuel or coolant dilution.
I've used about every brand of oil available since I've been driving. I've never had anything remotely close to sludge in my power plants.
Rumors are just that; a few anecdotal experiences have caused these rumors to be perpetuated throughout the ages kinda like the nonsense about waiting 1 hour to go swimming after you eat.
Pennzoil has been #1 one selling for what, at least four decades? So if someone has a sludge issue, they're going to blame the oil when in actuality the sludge was caused by something else like negligence or poor engine design.
EDIT: I was still typing my post when triple 7 posted. Great minds think alike!
Rumors are just that; a few anecdotal experiences have caused these rumors to be perpetuated throughout the ages kinda like the nonsense about waiting 1 hour to go swimming after you eat.
Pennzoil has been #1 one selling for what, at least four decades? So if someone has a sludge issue, they're going to blame the oil when in actuality the sludge was caused by something else like negligence or poor engine design.
EDIT: I was still typing my post when triple 7 posted. Great minds think alike!
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Not now as QS is a much better product, but in the mid 60's I used QS in 64 Valiant Slant 6. I bought the car with 13K and used QS with 2K OCI's. After 50K I had to remove the valve cover and the sludge had to be scooped out. I then switched to Valvoline. Finally in 1978 I changed to M1 5-20 and have never had sludge again.
No API SN oil is going to cause sludge if the engine is in good working condition and the oil is used as recommended by the mfg.
I'm convinced it's heat related. Gas engines that run in cold air like tractors plowing in cold frosty conditions (say Cletrac) get sludge under the valve covers. Same engine running hard in summer, no issue. Same with the gas farm trucks. To me, it's a form of condensation on cooler surfaces.
I've had sludge in marine engines that run a 160*F thermostat and direct raw water cooling. Same engine, same oil with heat exchanger running over 180*F, no issues.
I guess Mobil1 was the most impervious to this... But Pennz Ultra has to be a step up with GTL. And now Rotella T6 10W-30 is GLT based, so we'll see ...
I've had sludge in marine engines that run a 160*F thermostat and direct raw water cooling. Same engine, same oil with heat exchanger running over 180*F, no issues.
I guess Mobil1 was the most impervious to this... But Pennz Ultra has to be a step up with GTL. And now Rotella T6 10W-30 is GLT based, so we'll see ...
You might consider reading 'better' material from fact-based and informed sources and listening to different "rumors."
But you've come to the right place!
But you've come to the right place!
I purchased a 68 Impala Custom back in 1980 from the original owner. It had 77k miles on it. He used nothing but Quaker State Deluxe oil in it at 3k mile oil changes. At 100k I was getting popping up through the carb at high RPM. Turns out the number 2 intake lobe was worn. Which is a know problem on the 327 engines. So I tore it apart and rebuilt it. When I opened it up it was very clean inside. To my surprise from hearing all the rumors of sludge built up. After the rebuild, which I put back to stock except for a Crane blueprinted 300hp, 327 cam. Which didn't do much since I still had the single hump heads. I didn't ad them for a long time. When I sold the car it had a total of 180k on it with 103k on the rebuild. Ran great with no issues.
Obligatory:
Supposedly, there was an issue with QS.....either late 60's or early 70's.
That issue was resolved LONG ago and was short lived.
I would not worry about QS now.....as oil chemistry is MUCH different now anyhow (Again, the issue was resolved back then).
That issue was resolved LONG ago and was short lived.
I would not worry about QS now.....as oil chemistry is MUCH different now anyhow (Again, the issue was resolved back then).
Originally Posted By: NHRATA
Over the years I have heard many rumors about Pennzoil and Quaker State causing sludge in engines. Today I read about Castrol causing the same problem. It seems the only major brands I never hear of any sludge problems with are Mobil and Valvoline. What are your guys opinions and real-world experience. I have heard that Valvoline has a very different add pack than other oils, could this contribute to less sludge in engines?
where are the rumors of Castrol sludging up?
Over the years I have heard many rumors about Pennzoil and Quaker State causing sludge in engines. Today I read about Castrol causing the same problem. It seems the only major brands I never hear of any sludge problems with are Mobil and Valvoline. What are your guys opinions and real-world experience. I have heard that Valvoline has a very different add pack than other oils, could this contribute to less sludge in engines?
where are the rumors of Castrol sludging up?
1991 wants it's rumor back.
Valvoline seems to be the #1 oil here. Rarely do I see someone buying pz or qs. Mobil1 is top synthetic here too.
Back in the 70's and 80's things were different today Pennzoil and Quaker State are not any worse than any other Dino oil.. I have used Pennzoil in the past for years and hundreds of thousands of miles and my engines stayed clean and running well to this day.
Hi,
Sludge is typically a product of many factors. IME these have ranged from using an incorrect spec lubricant (either by the OEM or used by the end user) for the application, poor maintenance and unsatisfactory engine design
Varnish is a different matter IMO and some lubricants certainly do perform better than others
Most modern "Branded" lubricant are excellent products when correctly specified, applied, and used as intended
Sludge is typically a product of many factors. IME these have ranged from using an incorrect spec lubricant (either by the OEM or used by the end user) for the application, poor maintenance and unsatisfactory engine design
Varnish is a different matter IMO and some lubricants certainly do perform better than others
Most modern "Branded" lubricant are excellent products when correctly specified, applied, and used as intended
Mobil 1 is top synthetic everywhere i think lol
Originally Posted By: wiswind
Supposedly, there was an issue with QS.....either late 60's or early 70's.
That issue was resolved LONG ago and was short lived.
I would not worry about QS now.....as oil chemistry is MUCH different now anyhow (Again, the issue was resolved back then).
I didn't believe those rumors when I heard them in the 80's, but I was wrong. Some brands of 10W-40 oil made sludge in my Mazda, even though I changed oil well before the manufacturer's recommended interval. The sludge never caused a serious problem, because I switched brands in time. Sludge made its last appearance in about 2002.
Supposedly, there was an issue with QS.....either late 60's or early 70's.
That issue was resolved LONG ago and was short lived.
I would not worry about QS now.....as oil chemistry is MUCH different now anyhow (Again, the issue was resolved back then).
I didn't believe those rumors when I heard them in the 80's, but I was wrong. Some brands of 10W-40 oil made sludge in my Mazda, even though I changed oil well before the manufacturer's recommended interval. The sludge never caused a serious problem, because I switched brands in time. Sludge made its last appearance in about 2002.
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