so if i stop buying Havoline dyno oil for $1.70 a quart and start buying RP synthetic for $7.00 a quart i can expect to get 2.5% better milage?----- let me think about that for a while!
--------no one is questioning the quality of the RP oil, just the cost effectiveness.

 

Those mpg improvements are laughable. Notice the mpg improvement isn't a percentage improvment in mpg but a percentage of DIFFERENCE BETWEEN the two mpg figures. Fudging the numbers to look the best. I use synthetics often and have confidence in them but you are far better off going with a MC blend or Dino and reducing the OCI than ponying up the $$$ for synthetics. Synthetics also tend to vaporize much faster than Dino and Blends so you have to add more synthetic between changes.

 

I would love to try and argue that Royal Purple is the best and most cost efficient but since my only personal experience with it is the 150 miles I drove today after the oil change I have no real personal experience to speak of with it other than now after the oil change there is a slight improvement in throttle response it's not huge but I can notice it. So when I have run this stuff for a few years and have no complaints then I can try.

 

I just run the mobil synthetic in my SOHC. And after 136k miles my original timing chains and tensioners are still intact.

 

I never have to top off my synthetic. No evaporation here. My cost is lower using Walmarts synthetic, and my OCI is extended 100% by going to 10K (with a new filter every 5K). To me the only issues are 1) is the synthetic superior to dyno and 2) IF SO, given the extended OCI, how much more does it really cost, and 3) are you willing to spend that extra amount for your engine? We need someone to obtain a link (from a non-biased source) comparing syn to dyno oils.

 

Why have an oil that outlives the filter. You take the time to change the filter and lose about a quart of oil in the process. So your putting on a new filter and basically ruining a quart of new oil by dumping it in the crankcase with 4 quarts of dirty oil. Just don't make sense to me.

Do some heavy towing or work the vehicle and you will see the vehicle will consume more synthetic.

 

Synthetic is better, no questions, especially in extreme conditions like pulling a trailer, stop and go, that kind of thing. But main point is, if you don’t extend your time between oil changes your wasting your money. My buddy swears by Amsoil, says it’s good for 25K mile oil changes. A lot of guys like Royal Purple because its specs out a little higher than Mobil 1. I found a government test on oil on the internet a couple of years ago saw a lot of statistical test results, and most of the name brands were just fine. Mobil 1 looked real good to me so that what I use. The main reason I use it though is so I don’t have to change the oil except every 10K miles. With 5 vehicles in my family, I’d be under one all the darn time if I used regular oil. I’d be using Amsoil and going every 256K miles if I could buy the stuff at the local parts store.

 

Well who knows what the future lies ahead of me but i plan on keeping my truck till it calls it quits. With an expected life span of my diesel of 300,000 or even 400,000 taking it easy of course, been running 5-40 rotella syn ( syn-dino blend sometimes) since 15,000 with 10,000 mile oil and filter changeouts . Truck now has 98,800. I will rebuild my motor when the time comes and will take pics and report back all my findings as what this synthetic has done for my motor. It will take a few years but what the hey!

 

we'll be here!!!

 

If my gassers had 14+ quarts of oil I'd run it 10k also. Diesels also have a much larger filter. The filter on the 7.3l is 3 times the size of an 820S filter.

 

Thats cool fellas, like i said, i baby it most of the time but do go on long trips and tow so it may take a few more years, LOL but won't forget. Had a friend run Q- State oil in his car back in the early 90,s and did a tear down after 70,000 or 80,000 and found major sludge. 3,000 mile intervals i assume. But not to alarm anyone, Q-S changed there formula a few years back because of this i was told and from what i hear, its better now..

 

My loyalty lies with AMSoil, not RP or Mobil or Motorcraft, although I don't think those oils are bad or anything, I've just picked AMS as my oil.

 

You have misinterpreted what I said. I'm saying you don't need to do Wallyworld's advertising. We all know they exist, we all know they have low prices, and we all know that you are not receiving one dime for your efforts. We also know Wallyworld will sell a substandard product to save a few cents if they can. So they may sell brand name products, and if you buy those you are probably fine. But they also sell mystery products that came from who knows where, probably China. They also pit the mystery products against the brand name stuff and tell you the only difference is price. They also offer no employee benefits, and try to put companies that do out of business.

On the main topic. I have found that true ester base stock group IV synthetics are vastly superior to dino oil. The issue was brought up about the oil outlasting the filters. All but the cheapest bottom feeder oil filters will last at least as long as the oil. If in doubt, use oil filters that are intended for extended use. I get Mobil1 Extended Service filters at my local Checker.

In a comparison between Mobil1 and Royal Purple, I think the RP is the better, largely because teh RP is a group IV base stock, which makes it more thermally stable, gives it better viscosity, and lower friction, which also means less heat and lost power. Mobil1 used to be a group IV but now uses a cracked and refined dino oil instead. In everyday use, you probably wouldn't notice the difference, but there is also a principle involved. Mobil1 also openly critisized Castrol for marketing a cracked dino oil as a synthetic but eventually ends up doing the same thing. There is a certain amount of hypocrisy there, and for me, I find that offensive.

BTW, Amsoil is an excellent synthetic oil, as is Redline. This leaves use with three good choices among true group IV ester based synthetic oils. Regular oil will give you service intervals between 3,000 - 7,500 miles depending on driving conditions. True synthetics give you service intervals between 15,000 - 25,000 miles. The synthetics last more than twice as long, but do not cost twice as much. They can also help the engine last longer and get better fuel economy. To me, this is a no brainer.

As far as independent testing of synthetic oils is concerned. Many universities have tested these oils, and every study I have found strongly supported the use of synthetic oils on engines that have been broken in.

 

1. i would never leave ANY oil in a motor 25,000 miles, even if it was synthetic and came in a gold plated bottle.
2. DINO oil can be had for less than $2. a quart. How do you figure that synthetic is "less than" twice as much? The cost is closer to 3 or 4 to 1.

 

LOL, I would never put $2.00 oil in my engine. In my local area, Motor oil ranges from $2.79 for the cheapest stuff up to around $6.00. I buy RP for $6.49 per quart. I would not touch any of the stuff under $3.00. Most of it is store brand generic or Quaker State.

I only do oil changes every 15,000 miles. Based on how the dino oil looked after 3,000 miles, I would not want to leave that in there for longer than that. I have extended my changed longer than 15,000 with no ill effects.

If the regular oil only lasts 3,000 - 5,000 miles, and the synthetic lasts at least 15,000 miles, then it is outperforming the regular oil by a factor of >3:1. This makes it much cheaper in the long run.

And this is not taking in to account mileage gains or increased engine longevity. I observed a consistent 1.2 MPG increase when I started using RP in my van. The van came with Quaker State in it when I bought it. I also noticed further improvements in mileage when I replaced the front and rear differential fluids with synthetic. The synthetic oils lubricate much better, and the reason they last so long is that the heat from the engine doesn't crack their molecules. Also the Oil is made from esters, which are a type of solvent, so the oil itself is a detergent. In comparison, the regular dino oil has to have detergents added to it.