I use QS HM with Slick 50 in all 3 of my vehicles and it is great. I have a 2002 Toyota Highlander with 97,000 miles on it, a 2003 Nissan Altima with 120,000 miles on it, and a 1992 F150 with 202,000 miles on it. Obviously, I love to drive and I personally change the oil in all my vehicles every 5,000 miles and have had no issues with sludge or anything else. All 3 of my vehicles run great and I would highly reccommend this oil.

Only oil that offers an additive. Vehicles that are taken care of and driven slowly keeps the need to switch to synthetic. Slick 50 seems to have my car run 45% to 55% cooler. Anybody that has the opinion that Quaker State causes sludge I find hard to believe but I've never used Quaker State motor oil without the Slick 50 additive. I'm one of the slowest drivers on the road coming from a stop to the speed limit. Running the vehicle at a lower rpm helps keep the engine cooler,gas mileage,helps oil protect the engine in return less wear and tear on the motor. Still while accelerating this way would cause more sludge build up. My vehicle has never lost power and never caused my fuel mileage to drop. I'd bought a 2000 Buick Century 2 years ago that had 81,000 miles has that ran 20mpg intown 30mpg highway. Using Q.S. Slick 50 my gas mileage stayed at 30.86mpg to 31.71mpg using the interstate 50% of the time. I've never burned oil or had any oil leaks caused by using this product. The oil is allways in good condition during an oil change (2-3000miles). Quaker State does not cause sludge or engaine damage, it prevents it.

This works the best when you need to fill an empty syrup bottle.

Their conventionals are as good as just about any other major brand name, and their synthetics are excellent, also good value for the money.

Quaker State and Pennzoil have both been products of the Royal Dutch Shell Corporation since about 2002. I had a friend of mine who owns a drag car tell me how much he loved and trusted Shell Rotella in his haul truck, but would never use Quaker State or Pennzoil in his car. That is the kind of biased thinking that taints the reputation of the brand because of their past. In fact Royal Dutch Shell's research and development is as well funded and as well staffed as any in the oil industry. Why would so many people think they would not provide their customers with a highly engineered, top quality product?

When I called the QS customer tech support line the tech person told me that there is virtually no difference between QS and Pennzoil synthetic. He told me to buy which ever one is cheapest. P.S.... he also told me the synthetic oil sold as the Wal-Mart store brand was bottled by Warren Packaging but was supplied to them by Shell, and was virtually identical to Pennzoil Platimum.

If any oil meets the API standards in today's world, it's good stuff

QuakerState makes good oil.
Eclipse06 - you are simply wrong. Urban legends about QS/Pz wax that causes sludge - are just that. Urban legends. In almost all cases sludge is caused by bad engine design, faulty emissions equipment or improper oil usage intervals (abuse).

Before bashing a type of oil - do a virgin & used oil analysis. It may explain some things that may be happening with your engine.

Regarding oil in general - any modern oil meeting manufacturer's specification and/or bearing API Starburst symbol is OK for non severe usage. Obviously there are better oils for different apps, but there is no brand name automotive oil on the market that causes sludge.

Please stop showcasing your ignorance and do proper research. Mechanics' smoke-break talk and your own anecdotal evidence amount to 0 scientific value.

Not a Good oil at all take off a Valve Cover off a engine that used QS and properly changed it as well, and yeah you'll know what I'm Talking About.

As long as you change your oil every 1000 miles it is ok.

  I send in used oil samples. QS green bottle shows the least wear in my 4.0 Jeep. I like it.

Engine is spotless inside.

This is terrible It does contain ltos of wax but many quick lube places use it and for response to darkknight pennzoil quaker state and q are all the same company read the back fo the bottle and website. 

Heres there parent companies website:

http://www.pzlqs.com

Quality motor oil is important. However, I have torn down very few engines that had a proper working thermostat that had sludge. Quaker State is excellent oil. If you engine has a thermostat stuck open; it does not matter who makes the oil, you are going to have sludge.

ok let me just tell you guys little secret, you an call it oils 101. For those dinoaurs out there that are too cheap to put synthetic oil in you vehicles and come on here and complain about sluge then you deserve to have crapy vehicles. Quaker State Q synthetic oil is the best bang for your buck, it cleans your engine an makes it run awesome, i believe that the Q is the best valued oil out there today.

good oil

Only used it a few times. Engine noise seemed more pronounced with QS.

Very bad oil in my oppinion!
creates a lot of soot- sludge in your engine.

In 1990 My friends father built a 327 for his chevy truck and he swore by quaker state. He changed the oil every 3,000 miles and when the truck had 15000 miles on it he found a set of corvette heads that he wanted to use. When he tore down the engine it had about a 1/4" of sludge in the valve covers. needless to say neither he or I have used quaker state since.

I sell pennzoil valvoline and quaker state. as far as performance based oils, quaker state is head and shoulders above. If you care about getting top performance out of your engine use it

i have never had aproblem w/ QS....my cavalier has 154k and still runs strong....50000 of those miles were Quaker state...3k oil changes are a waste of money, oils are very good nowadays...just use the right grade of a api certified oil and make sure engine has enough oil and you will be fine for 7500 miles under most conditions...just ask Consumer reports who tested the oils after nyc taxi service

jhiggs where did you get that BS! Quaker State uses the same group II virgin oil basestocks. It is owned by Shell. Have you ever compared an virgin oil analysis and compared Quaker State to Valvoline. Quaker State has more additives.

Valvoline is about the same price is is a better oil... Quaker State is just recycled oil with a big marketing hype and lots of different labels.

Quaker State rocks!!! Be it the conventional or the synthetic versions your vehicle will thank you. I'm a police officer & have used Quaker State in both the Chevy LT1 Caprice & the old & new version Crown Vic's. No problems ever & those cars were pushed hard. Car's were still running fine with 350,000 KM's on them. No engine problems at all.
And stay away from Pennzoil & Castrol folks...unless you want big repair bills.

We used Quaker State Peak Performance Conventional 10w-30 and 5w-30 in our cars for at least 5-6 years and we never had a problem. In all the tests I believe it was up there with the leaders just a good all around motor oil for your everyday driver. Now I'm trying Valvoline Maxlife just for a change of pace and because Q-State is currently now the same price as regular valvoline conventional at Walmart. One other reason I decided to switch is since I believe 2002 Quaker state has merged with Pennzoil becoming the Quakerstate-Pennzoil Company & if you notice on the bottom of the little green bottles it will tell you that, I didn't even realize that until about 2 years after they merged & my opinion of Pennzoil isn't so hot. But as long as you aren't trying to race with this conventional oil and maintain 5000km or 3000mile oil & filter change intervals I would recommend this oil due to my past experience with it.[Biggest thing is O&F-5kmOr3m]

Used quaker state in a brand new car after breakin,All i can say it is very poor oil if it gets brown after 3 days driving,any good quality oil will not do this,checked with other people and same thing,went with valvoline and stays golden color for a long time,Lots of quaker state hype thats all i can say.

That dude is wrong- the Q oils SUCK tried it in my maro i've gotten better-much better performance from so-so conventionals. I don't know why I even tried the oil I knew Q State sucked.

The only quaker state oils that i would give a 5 to is their new Q oils. I have a 95 5.0 mustang that i occasionally drive in good weather and i run the Q Advanced Engine formula. My mustang has a few mods giving it a around 350 horsepower. The Q oil performs great. You may not believe it but i actually can tell a difference in performance at high rpm in 3rd and 4th gear. I was sceptical of trying this oil because i have heard that quaker state oils have not been all that they have said to be in the past but i decided to give it a try and i was impressed. If you are thinking about puting any other q state oils in your car besides q don't because im not too sure about the other oils, that person who said that they changed their oil formula in 1981 is full of it, if you look at the dates of 11-8 and the times that person was the one who said all of that about the new formula but i can agree with that person about the Q oils.

I've been using QS for yrs and have never had any problems in any of my vehicles and i've had many gm v6 s& v8's and mopars v6's v8's big block or small. The oil valleys and passages have always been clean and the drivetrain ash and soot free.

My engine is the 3800 Supercharged Series III, with stock- 260 Horse. Now I have done a few minor things to the engine to get it have 285 Horse, such as changing the supercharger pulley. I noticed that the regular oil changes from GM were not keeping up with the beating that engine receives from me. So I told them to start using Full-Synthetic Oil... GM recommended it due to it being a high-performance motor. I noticed a IMMEDIATE changee. I went with QUAKER STATE HIGH PERFORMANCE , I used it twice ( before wrecking the car) 10w-30 was the first, then 5w-30... The difference was in the engine feel and sound. It went from feeling like it was screaming for oil to saying " bring it on" I mean I was shocked. Such a nice smooth sound instead of that "Oh come on.. dont make me do this" Driving 6 straight hours on the thruway challenged it too. 90MPH is what cruise was set at... ( Yeah I got a ticket right when I arrived) but I could still beat on that engine and it still sounded nice and smooth. Not a care in the world. I dont know that much about engines and what have you, though I did work for a GM licensed dealer for a while... but I do know enough to know this oil made my engine perform better, the temp didnt rise up as much. Overall I will use it again. I now use it in my Buick Park Avenue with the Supercharged Series II engine.. and once again smoother then it was.

I have a 1990 ford escort with a 1.9liron block in it and have owned it since 25000kms.I use quaker state synthetic in every engine in my hosehold and have used it in the escort since the first day that I had it in the driveway.Not what you call a car with a lot of initial quality in it.I also live in the most corrosive part of north america,the east coast of Canada.I change the oil at the proper intervals and maintain the car as best as I can.790000kms later it still works like a charm and is all original under the hood except for the starter and the rad.My mechanic cant beleive how little wear it shows,certainly has been an excellent product for me, I'll never use anything else.

I hear you can cook frys with it but I wouldn't put it in any of my cars. I tried it for a while and I was always a quart low about 1000 miles before next change. I switched to Chevron and I can go an other 2000 miles further and still not need any oil.

most overrated oil except maybe mobil.

Quaker State did change thair formula in 1981 and since then have used the same maybe made some changes. I agree it wasn't great back then but now it works the best. Ilove the new Q synthetic iin my 01 CamaroSS it has more power than any other oil.

Deffinitely the best.

Let me tell you that the new Q works FANTASTIC.My dyno results are the BEST ever since swithcing to Q.I also know that there conventional is great aswell.

i like using quakerstate i use the 10w-40 synthetic blend in my truck and she runs great getting ready to switch my girlfriends corolla over to quakerstate since penzoil is creating a wazy build up

Always works excellent... never a problem

I agree with Flick01,although I have never had a personal experience with quaker state oil,my family and friends have told me to stay away from it because it was a bad oil to use in my automobiles. Im glad I listened to my family,friends over the years and have never used you product,and will never use it now.

I would hope that their formula has improved because in the 1970s one of my fellow car enthusiasts used Quaker State in a 1972 Chevelle and faithfully changed the oil and filter at 2500 mile intervals. (He purchased the car new) One day we pulled the valve covers and were horrified to find a white-ish kind of material...... almost like a sand in the cylinder heads. After cleaning the heads we both swore that we would never again use Quaker State. Once my friend switched to a different brand of oil, the problem did not return. I am sure that improvements have been made but as the saying goes, Once bitten, twice shy.

I use this oil now in my everyday driver. I actually buy the Wal-mart exclusive oil Tech 2000.....Quaker State make it, and it's only 80 cents a quart.