The owners of this Taxi Fleet are not guessing or hoping anything. There bottom line is cost/effectiveness. You can go on
http://www.auto-rx.com and type in MPG on home page website and read other posts regarding MPG.
This test was done by Larry Lux (some of you know him and the professional level of his test criteria) This report is posted just as received.
Frank,
Here is the first part of the test results.
Taxi tests, six cars all Ford Crown Vic’s
Notes on tests:
All cars were driven by taxi drivers in regular service in good weather. Mileage was tested and hand calculated at the start and was compared with Scangage readings. The Scangage was used for all future readings. The errors were consistent, that is, if it was 4% off it was 4% off on every tank, for a given vehicle. Error rates ranged from 2% high to 7% high for different gages on different cars and since this test looks for trends not absolute values because we were using different vehicles the Scangage readings were accepted. One thing in our favor is that the same driver always drove the same car.
All vehicles were serviced every 3k miles and conventional 5w-30 oil was used. Each car was driven for 500 miles to get a base line for mileage and then the testing began.
Vehicles
1 & 2 received Auto-Rx and the driver was aware of the test.
3 Driver was aware of the mileage test but was told we were testing mileage with different tire pressure settings but did receive Auto-Rx..
4 Driver was aware of test but we used an engine flush.
5 Driver was aware of a test but also was told it was a mileage test with different tire pressures. This was also an engine flush car.
6 Driver was aware of the test but was again told it was a tire pressure test and received a gas additive which was really regular unleaded gasoline with a blue dye.
All vehicles were run with 40psi which is the usual pressure for the fleet.
Mileage varied a great deal between cars and is the result of very different driving styles. All vehicles improved their mileage numbers when the test began over the first 4 thanks of fuel. At the beginning the worst was 11 mpg and the best was 16 mpg during the 500 mile pre test run. The average improvement over four tanks was 3% from the actual start of testing.
The Scangage readings for gallons per hour at idle were recorded and all vehicles read .5 to .8 gph.
All cars were in good working order with odometer readings from 180k to 455k. The 80k vehicle was considered a new car by the drivers and the 455k an average vehicle that would be kept until it’s first major accident. Other than accidents these Crown Vic’s are kept until about 550k miles before being parked and used for parts. They are only put out at about 550 because there are rules about not using cars over 10 years old.
The point of this test is to see if Auto-Rx is worth the cost of the product and taking the time to add it at every PM (preventive maintenance)
The Auto-Rx vehicles (1,2,3) received 20 ounces and then 4 ounces every 3k oil change.
Cars 4 and 5 received a popular engine flush, one sold by dealers and the other available at your local parts store. The directions on the label were followed.
Car 6 received a very expensive gas additive. It costs about $1.88/gal (unleaded regular gas) plus the blue dye.
We did not do lab work and the test was aimed at taxi cab use so you don’t need to take shots at the fact that is does not meet your needs. These cars see more hard use and more maintenance than you are likely to experience. We tried to get pictures under the valve covers but it did not happen. The mechanics messed up the camera, and we never recovered the pictures taken. Also no one volunteered a replacement camera.
Numbers at the start of testing.
1. 15mpg, .6pgh at idle
2. 13mpg, .7gph
3. 14mpg .5gph
4. 15mpg .6gph
5. 12mpg .6gph
6. 15mpg .5gph
Auto-Rx was added and 2 engine flushes done
3k PM, 4oz of Auto-Rx added to cars 1-3
Numbers at 6k miles, after the second PM
1. 17mpg, .5pgh at idle
2. 16mpg, .5gph
3. 15mpg .5gph
4. 15mpg .6gph
5. 12mpg .6gph
6. 15mpg .5gph
Numbers at 9k miles after third PM
1. 19mpg, .5gph at idle
2. 17mpg, .5gph
3. 16mpg .5gph
4. 14mpg .6gph
5. 13mpg .6gph
6. 16mpg .5gph
Numbers at 12k miles after fourth PM
1. 18mpg, .5gph at idle
2. 17mpg, .5gph
3. 16mpg .5gph
4. 14mpg .6gph
5. 13mpg .6gph
6. 16mpg .5gph
Notes on cars 1-3: Drivers reported idle readings often dipped to .4gph in the day time when a/c and lights were not on. We checked readings on several new caps (vehicles with under 200k miles on them) and did not see any .4gph readings. We checks several really new Crown Vic’s, Police cars and several had .4gph readings. Please note that all theses cabs in the fleet are X-police vehicles.)
I have not put the numbers into a spread sheet but that is coming as I get the time.
More comments:
It was decided that Auto-Rx is worth the cost and effort on mileage alone. We did look under valve covers and they went from dirty looking but not sludged to clean looking where you could see the actual color of the engine oil on the three Auto-Rx cars. The 2 cars that got flushed did look cleaner but did not have that clean look of fresh oil and left significant deposits behind. It was though that additional flushed would be needed so as a side test we took a seventh car and did three flushes over 9k miles. At 3k miles the results looks similar to cars 4 and 5. The next two flushes showed little or no improvement. The compression readings on this vehicle never changed from before the flush to after the third flush.
The untreated engines looked the same before and after.
The Auto-Rx treated engines all showed improved gas mileage and the mechanics commented that they ran smoother and the plugs looked cleaner. I am still putting compression numbers together but all Auto-Rx engines showed improved compression and the flushed and non-treated engines showed no change. This the mechanics said shows that the rings where actually being cleaned and allowed to better seal the combustion chamber. They said that this would not only improve performance but would help to protect the engine oil. The mechanics all agreed that this was the first product they thought lived up to it’s billing. They said they were skeptical at first but after this test they agree that Auto-Rx works.
