Since it was time for an oil change I thought I would try out some of the Royal Purple 10W-30 motor oil since my engine only has 8,000 miles on it. While I was at it I also installed RP gear lube in my tranny, t-case, and both differentials. The RP sales literature claims that if you use all syth products your gas mileage will improve by a small percentage.

I'm heading to WV at the end of the month (a 6 hour drive) and I'm going to see if the claim is true. Dad consistently got 19 to 19.5 mpg on the hwy.....IF I get 20 mpg or better then I'll know the synth lubes worked.

I'll post up data once I get it.

BTW the truck does "seem" to like the synthetic oil. But then....maybe it's just me consoling myself on spending $5.35 a qt on motor oil.

 

While synthetics have a lot of advantages over dino oil, you'll most likely not see an increase in gas mileage.




Fred

 

There could be hundreds of factors that could net you an extra .5 mpg, so any results may not point directly towards the Royal Purple treatment. This is especially true considering the mpg rates are being achieved by two different drivers.

 

I recognize the value of synthetics. On a low reving motor like the 2.4L, not using for towing, not under any particular stress, I don't use synthetics - just doesn't make sense to me.

Turbo and stressed motors yes, the turbine alone can be 1200 degrees, enough to coke conventional oil.

However.. What I am buying into now, after trashing a few turbos via new engine debris is higher dollar oil filters - The one I'd been using - the Fram, turns out to be really bad as a filter.

http://minimopar.knizefamily.net/oilfilterstudy.html

 

fram (and any other brand oil filter it makes) is complete crap, i buy Toyota oil filters.

I use royal purple in my 4runner and i didn't notice a change in MPG yet... but iv haven't driven much and haven't changed my rear diff with their syn gear oil. I'm interested to see if your MPG actually increase.

 

well my truck gets 24 mpg + on the highway, with the same old dino gear oil that i put in it nearly 2 years ago, so don't count on any deffinitive answer out of that experiment

 

I never said I was holding my breath about their claims but I plan to see if it works. The two biggest reasons I went with the synthetic is 1) less frequent oil changes and 2) I flat tow my samurai, so it does see some light duty towing.

I generally stick with regular dino in my vehicles with consistent, regular change intervals.

With the RP I'll only need to change it twice a year, so I may actually save some money using the synthetic. I believe most people only change their gear lubes once or twice during the time they own their vehicles.

 

just changing all of the fluids should help. doesnt matter what you put in there. as long as the old stuff is starting to break down having some better lube has to make a difference.

 

Synthetic gear lubes run much cooler than stock fluids - not a huge temp difference but over the span of your gears/tranny/transfer case it can add up. Amsoil claims I can double the interval for changing my gear lubes. That is nice insurance to have. Whether their is a mileage difference or not - it's probably negligeable or very minute. But it's just nice knowing you are protecting your gears better, and you have the insurance of longer intervals if you so desire. In the end it makes the synthetic gear lube change a bargain.

 

I'd just run an easy to get synthetic and not pay a premium for anotehr synthetic especially on a stock engine.

 

I used it but I didn't see notice any difference that would justify the price. Maybe if I had a blower or a turbo but not in my 3.0

 

Gear oils are fine for long intervals unless there is dirt or other contaminants (water, etc) in the oil. Synthetics have a higher temperature capacity and therefore can last a lot longer than dino oils.

+1 on synthetic gear oils. They are more slippery and therefore run at lower temperatures, and have a wider temperature range and load range. Less friction translates to higher efficiency and possible increases in fuel mileage... but tires with a smoother tread will make more difference

 

You have my consolences....