Ok, so my new Rubicon is going to be here soon. I want to keep this vehicle for as long as possible and am curious to hear what you all think about Royal Purple and other premium fluids. Is Royal Purple worth the $15 - $18 a quart? What about transmission fluid, gear fluid, etc? Thanks all!

 

What this shows:

Ideally a good quality gear oil will be in the gray area before and after the test. Lucas 75/90 Synthetic, at 22.35 cSt, and Royal Purple Max-Gear 75W-90, at 19.32 cSt, both exceed the maximum 18.49 cSt initial viscosity (red), failing the SAE J306 requirements for SAE 90 gear lubricants. All other gear lubricants were within the required high-temperature viscosity range prior to the KRL Shear Stability Test.

Viscosity measurements following the KRL Shear Stability Test revealed that seven gear lubes sheared down below the minimum viscosity requirements (orange), failing the shear stability requirements of the SAE J306. The two gear lubes with the largest viscosity loss, as reflected in the following graph, were Royal Purple, losing 40.6% of its viscosity, and Torco SGO Synthetic, losing 35.2% of its viscosity. Royal Purple was the only gear lube to fail both the initial viscosity requirements and the shear stability requirements. It started out too thick and ended up too thin.

So in other words, after 20 hours the royal purple and Lucas failed miserably and the Pennsoil, Mobil1, Mopar and GM oils, and Torco all lost so much viscosity that they really were not even the same weight oil anymore.

Full test here: http://www.amsoil.com/lit/g2457.pdf

 

 

Used Royal purple once and was very disappointed.
Very poor performing, and gas mileage dropped almost 1mph.
I've always used Mobile1 Full Synthetic, and it runs very smooth.
Went with royal purple once to see for myself what all the hype was about and found it to be not.
Just my experience with Royal Purple, it's not worth the money.

 

I found the complete opposite whenever I went from mobile 1 to royal purple. The jk idled smoother and ran better. Im not going to use it again, I change my oil every 3,000 miles and a 50 dollar oil change is not going to happen every time.

 

Joe: Thank you for the breakdown. That is some serious analysis, but your bottom line, if I understand, is not to waste my money on Royal Purple.

Jayhawk: Exactly what I did. My boys kept asking "Daddy, does your head hurt?" Just kidding.

Southbay and Red: Thanks for the user level experience. Like Red said, $50 oil change regularly is a bit much. If I change regularly, I think I will be ok.

Looking at the chart, I am thinking about looking into AMSOIL or Redline, but have not heard of those and wonder how hard it will be to locate. I have a bit of time.

Thanks again guys. This is my third thread on here and I can't believe how helpful everyone is. This forum embodies the Jeep spirit.

Cheers!

 

i don't have an opinion on any oil and find the chart interesting and possibly very useful when it comes time to change those fluids. but, there could be a chance that the chart could be a little miss leading since its Amsoil who did the test. like any good company trying to sport their product, it's the one that performed the best in the tests. so, just saying that this just may not be a 100% accurate.

 

These oil/lube questions are as old as the hills and then some. Some people aren't happy until they have purchased the most expensive oil they can find. I've only been running vehicles for 50+ years, so I don't know it all, but any oil that meets the manufacturers specs and changed as per their recommendations, is all that is needed to get the most out of your new Jeep. I've been through all of the Amzoil, Lucas, Mobil 1, Valvoline hype over the years and none of it makes any difference in the life of car/truck/jeep as long as they are serviced regularly. I can't recall ever losing an engine, trans, or differential that was caused by failure of the lubricant. You can spend $18/qt or $4/qt, but the results will be the same. Maybe the $18 oil will let you sleep better (until you figure out what the extra $70/change could buy) but the Jeep won't care.

 

Amsoil Amsoil....PM me and I can save u money.

 

I use royal purple but amsoil might be the next change here soon for me