I have a 17 year old Volvo TAMD41P-A diesel in my 31' recreational trawler. Prior engine oils for the prior owner (11 years) and me have been 15-40 dino oils, until I switched to full synthetic engine oil, also 15-40. Operating temperature dropped 5 degrees at standard cruising RPM of 1800 to 2200 (only one of two thermostats in place most of that time), the engine runs quieter and more smoothly. Based on research I have found, I know that my engine is running cleaner, with other attributes of reduced internal corrosion, less wear, etc. After installing 2 new thermostats, the engine runs precisely on specification for operating temperature through the full range of RPM, right up to wide open throttle, 3800 (end of the day 10 minute spike to clean the exhaust system ). Further, smoke when starting is greatly diminished to almost zero. I am completely satisfied that I am doing all that I can to accomplish optimal engine performance and protection with Rotella T6 over the last two years, and I am comfortable recommending Rotella T6 to boating friends with diesels, confident in the cost/benefit of using the best oil quality, grade and viscosity for my application.

I have been using this oil in my 1998 Honda F6 Valkyrie Tourer for 6 years now, and have had no issues with clutch operation. Even at full throttle with the big 6 cylinder engine, no clutch slippage. Also, the notorious Valkyrie top gear whine was a lot quieter immediately after the first oil change. It's also priced a lot cheaper than the competing oils, a nice added bonus. I don't hesitate to change the oil when I should, when the price is about half of other high end or OEM oils. It's available at many local retailers, so, it's easy to obtain. I wish it was available in other weights like 5W20. I would use it my 2010 F150 5.4L if I could, because it's really not that much more expensive than conventional oil.

I use this Rotella T6 in all my cars with synthetic requirement for oil. Its low weight and high viscosity - good stuff. Holds up well in my 350HP turbo application and also lasts the 7,500mi interval for my non-turbo car. I have even started trying in my motorcycle and so far seems good.

Used it twice so far in 2002 Jetta TDI. Usually use Castrol Syntec 5W-40. But I like this product as well and it has a nice price tag at Wal-Mart. Jetta has about 185K miles on it. Wal-Mart also has the three pack for about $60, which makes for about a $30 oil change (remember for a Jetta almost 5 qts are needed- $20 for the gallon + about $6-7 for 1 more qt +oil filter).

I have been using ROTELLA Full Synthetic for 10 years in my Honda ST1300. I Change it every fall when putting the bike away for the winter. I have 180000 km on the bike. It does not burn a drop of oil. This bike is not a stranger to the far side of the speedometer.

I have been running shell oil since I bought my duramax in 2002, the truck has been used for construction in northern Alberta in the oilfield it’s entire life. Big trailers, -30C morning starts, working lots of hours , Shell’s fluids have never let me down. The truck has 800000 km- 12000 engine hours on it and the engine runs as good as it did the day I drove it off the lot. Doesn’t use any oil at all from oil change to oil change. I Switched to t6 at 400000km and run the 5w40 year round. I change oil every 5-6000 km. If your looking for the best fluids to run in your diesel pick up this is it.

We run it in gasoline-powered endurance race cars now. Same protection as Mobil1 0-40 we used to run, but way cheaper and more available. Once had a car come in with a badly warped head, no coolant, and boiling oil (coolant hose burst and the driver didn't notice) - over 10 minutes out on track without coolant! Still kept the rods in, no hard parts got damaged. Highly recommended! I use it in street diesels and my motorcycles, too - also works great there.

This oil is made for hot running engines and we know what heat does to things. Many Harley Davidson riders have gone to this because it has all the protection that an air cooled engine needs. We all know how many miles a diesel truck puts on the road while delivering across the nation and how many times we have sat behind one waiting. Heat is the enemy of oil and keeping the engine parts slick is long life for the engine. When you start that engine for the first time in the morning it has parts that need to be coated and slick... that's where Rotella comes in and it adjusts through the day's temperature and the season temperature. Engine manufactures have determined that it should be changed at or around the 5,000 mile mark.

i have buying t6 full synth 15-40 for my two powerstroke 05 ford 6.0 diesel and 08 ford 6.4 diesel in my 6.0 engine i change every 2000 and at the most 3000 miles and because after 1000 the shearing is very noticable at 500 miles its completely black i now the 6liter are hard on oil but i have spent well in the thousands in oil changes just year rotella t6 nothing else

Rotella T-6 is a sleeper in the motorcycle world. I have run it in an XR250 dirt bike off road (which is a serious test of how it works in a wet clutch.), a Honda VFR800 sport bike and a Honda Shadow cruiser. Zero problems or issues of any kind. Blackstone lab analysis showed a very good additive package and essentially zero wear after a hard run in the sport bike. This oil is JASO MA rated for wet clutches. The price is a bargain relative to "motorcycle oils". Being a 5W-40 this oil starts easier in cold weather than petro oils. I also use it in a generator and my gas powered pick up truck. This is possibly the most versatile motor oil made. Excellent stuff. (No... I don't work for Shell oil !!)