SUVs and Their Lubricants

I took advantage of the trips my wife and I made over the past summer and fall to test drive some of the more popular brands with an eye toward making a purchase in the near future.

As a reference point, I’m using my current vehicle, a 2008 Nissan Quest minivan. This one has been an excellent vehicle. Currently, it has over 156,000 miles on it. It has a 3.5L V6 with fuel injection, fuel economy in the 16-24 miles per gallon range and delivers 235 horsepower. The lubricant requirements for the ’08 are typical of the era. The recommended engine oil is an SAE 5W-30 API SM-Resource Conserving (equivalent to ILSAC GF-4). I have always used SAE 5W-30, even in the hot Arizona summers, and to this day oil consumption is minimal. 

For the most part, the oil changes have been in the 7,000- to 8,000-mile range, and the product used has been a semi-synthetic. Until recently, we have averaged about 21 to 22 mpg. Old age has begun to catch up with the Quest, and fuel economy is slipping to around 19 mpg. I’ve mentioned before about our frequent treks from Arizona to Southern California. Each trip was about 800 miles. 

For the Quest, the transmission fluid called for is Nissan Matic K. As you probably know by now, there are about 100 transmission fluids currently specified by OEMs and each is somewhat unique. Nissan’s recommendation includes a statement that there could be loss of performance and possible transmission damage if the wrong transmission fluid is used and that it will not pay for repairs. Fast oil change and non-OEM garages need to know about the specific requirements for each transmission. I’ll remind everyone at this point to read their owner’s manual for the proper transmission fluid recommendation.

In my working days, I traveled some with one of our sales reps. He was an old hand whose view was that a test drive at the dealer was useless. He rented various types and brands of vehicles when he was traveling so he could get a much better feel for the good, the bad and the ugly of any vehicle. That made sense to me, and my experience with this project confirmed it. If you believe you can tell whether or not a car is right for you based on a 15- or 20-minute test drive, that’s great, but I can’t. 

My plan included renting various intermediate SUVs to see if there was one that stood out. Naturally, I was interested in the lubrication aspects of each vehicle and how it relates to vehicle operation. Automotive lubrication seems to be at two opposing ends: Standard API recommendations cover engine oil performance, but transmission fluids are brand or unit specific. 

Note that all of these vehicles were model year 2019, so ILSAC GF-5 was the appropriate specification. API SN-Resource Conserving would have been another appropriate option, unless the engine was direct injection, turbocharged and gasoline fueled—then it was API SN Plus-Resource Conserving. This reduces the risk of low-speed pre-ignition problems. ILSAC GF-6A and GF-6B are the new norm beginning this month and address the LSPI situation for new cars. 

Recently, a question of LSPI occurrence with aged oils has developed. While engine oil specification development committees have not received any specific complaints, a used oil version of the Sequence IX engine test is under serious investigation and will probably impact future oil standards. (See Page 32 for more.)

First up to rent was a 2019 Mazda CX-5. This trip was in Maine, where I was able to evaluate performance on both interstates and secondary—even tertiary—roads over four days and 730 miles. I was looking for ease of handling, fuel economy and general comfort. According to Mazda literature, the CX-5 2.5-liter L4 engine delivers 187 horsepower with a 6-speed transmission and is rated at 25 mpg city and 31 mpg highway fuel economy. It calls for regular gasoline. The lubricant requirements for the SkyActiv engine include SAE 0W-20 or SAE 5W-30 ILSAC GF-5. The transmission fluid recommended is Mazda Original Oil ATF-FZ. 

The safety features on the Mazda gave us a big surprise. The collision avoidance package is amazing. In one instance, I was driving on a three-lane freeway in the middle lane when a car passed me on the left and then cut across both lanes to an off ramp. I went from a comfortable 65 mph to less than 25 mph without even reacting to the other guy’s impulsive move! I was stunned and pretty sure I wouldn’t have reacted as quickly. 

The next car we evaluated was a 2019 Jeep Cherokee. We drove this one from Phoenix to Orange County, California, and on to Coronado, California. This drive was intended to see how it would do in a hot desert environment as well as in traffic. Interstate 10 runs through the desert where temperatures can reach as high as 120 degrees Fahrenheit in the summer, and road and traffic conditions are not optimal. We covered 1,211 miles over several days and found it to perform well. 

Fuel economy is quoted at 25-31 mpg on regular gasoline. The lubricant requirements for the Cherokee with the 180 horsepower, 2.4L non-turbo include Mopar-branded SAE 0W-20 engine oil meeting FCA Material Standard MS-6395, which has the same performance requirements as ILSAC GF-5. In the case of engine oils, the owner’s manual identifies Shell and Pennzoil GF-5 products by name as two oils that meet the requirements. The 7-speed automatic transmission calls for Mopar ZF 8&9 Speed ATF or equivalent. 

The second day we had the Cherokee, we got a warning light that said the airbag deployment system needed to be serviced. That always raises an eyebrow! It went away after a few minutes, and we chalked it up to a gremlin in the electronics. However, it popped up occasionally throughout the trip. In spite of the warning light issue, we found the Jeep to be a satisfactory vehicle.

On another trip to Orange County, we rented a Ford Edge. Again, this gave us a feel for high-temperature desert driving and performance in traffic. Fuel economy on the Edge is quoted at 22-29 mpg, less than the non-turbo Jeep and Mazda. In addition, the fuel recommendation is premium gasoline. The engine is the 237 horsepower 2.0L EcoBoost. 

This was the first direct-injection turbocharged engine we encountered. The engine oil recommended is an SAE 5W-30 Motorcraft WSS-M2C946-A, which has the same performance requirements as API SN Plus-Resource Conserving, including the Sequence IX LSPI test. The transmission lubricant is Mercon ULV Automatic Transmission Fluid XT-12-QULV. It was a good ride from the start.

The last SUV we rented was the Chevrolet Equinox. We picked this one up in San Francisco and traveled nearly 500 miles in four days. We evaluated the Equinox on some really rough roads, including dirt, paved and even on a bridge that was paved with rather large rocks. (Point Reyes Lighthouse is very remote!) 

This was the first vehicle where I sensed the lane-keeping assistance feature. As we were driving on an interstate, I noticed that the wheel turned in my hands as we went around curves. I basically let go of the wheel and the vehicle followed the white line. All in all, this was an excellent ride.

The fuel economy quotes for the Equinox are 22-29 mpg, which is comparable to the Ford. It was powered by the 252 horsepower 2.0L turbo engine and 6-speed automatic transmission. The lubricant requirements for the Equinox are as follows: Dexron-VI Automatic Transmission Fluid and an engine oil meeting the Dexos1 specification, with AC Delco Dexos1 being recommended. 

It is important to understand that Dexos1 is not just the API or ILSAC standard. It includes the tests (or similar ones) that are a part of the current API category as well as additional tests designed to give Dexos oils international performance capability. That’s the result of GM’s need to use a single oil standard globally. In North America, ILSAC GF-5 and now GF-6 are acceptable in GM vehicles.

So, what did I learn?  First, the engine lubricant requirements for the latest engines are an upgrade. API SN-Resource Conserving (equivalent to ILSAC GF-5) was the standard for 2019, but starting on May 1, the new standard is API SP (equivalent to ILSAC GF-6). 

As a reminder, GF-6 includes two sub-specifications: one for the same viscosities as GF-5 and SN, plus one for SAE 0W-16. This lower viscosity needs a different Sequence VI fuel economy test procedure to correctly measure fuel savings. GF-6A is backward compatible, but GF-6B is not, due to its low viscosity.

Second, LSPI is a situation that needs to be addressed. New oils—API SN Plus and API SP—demonstrate resistance to this potentially serious problem. However, there is growing concern that used oils may not be adequate and that a new or more likely modified Sequence IX test will be needed to demonstrate the necessary protection. 

Third, these new engines are really fun to drive. I found that they were very good on fuel economy and performance, especially when I was driving a vehicle with a turbocharged engine. There is no doubt that engine technology has made major strides over the last 10 to 15 years.

The last thing I was reminded of is that the transmission lubricant market is extremely fragmented. It seems that every transmission type and brand has its own lubricant requirements. The transmission service industry has an almost impossible task to stock the necessary products. If the wrong oil is used, warranties may be voided, and if aftermarket boosters are used, there is some doubt that the transmission fluid will meet any specification. The industry needs to come up with a classification system similar to API’s Engine Oil Licensing and Classification System. 

This looks like a new project for the main players (OEMs as well as oil and additive companies), so let the games begin!