A review of mine from the Powertrain and Fluid Meeting, October 29 - November 1, 2007:
Low Volatility ZDDP Technology: Part 2 - Exhaust Catalysts Performance in Field Applications, Bardasz et al, Lubrizol; Hubbard et al, Ford Motor Co:
Six 2003 NY Taxi Ford Crown Victoria 4.6-2V V8 cabs were run over 100,000 miles over 2 years on a dyno using the FTP-75 driving cycle. Oils were changed at 5,000 miles with a 5W20 GF-4 SM conventional oil. Three cars had “conventional” ZDDP and the others had low volatility ZDDP both at a phosphorous concentration of around 0.75.
After the test period the O2 sensors showed no unusual deterioration. The catalytic systems were taken off the cars and tested for working efficiencies by Southwest Research Institute in San Antonio, TX.
Both oils maintained “excellent” antiwear and antioxidancy engine performance.
There was a 30 % reduction of deposits on the low volatility ZDDP cats.
Improved THC light off times.
NO emissions reduced 10 %.
CO emissions were lowered by 50 % after the forward cat and 15 % after the second cat.
(This means to me that there is much more reserve left in the system using the low vol ZDDP)
One car using the low volatility ZDDP but with the highest oil consumption showed no improvement over the regular ZDDP cars.
This is one study that seems to be well done and shows that both oil consumption and the use of high volatility ZDDP results in significantly higher catalyst deterioration. Note that there are multiple ZDDP formulations.
aehaas
Low Volatility ZDDP Technology: Part 2 - Exhaust Catalysts Performance in Field Applications, Bardasz et al, Lubrizol; Hubbard et al, Ford Motor Co:
Six 2003 NY Taxi Ford Crown Victoria 4.6-2V V8 cabs were run over 100,000 miles over 2 years on a dyno using the FTP-75 driving cycle. Oils were changed at 5,000 miles with a 5W20 GF-4 SM conventional oil. Three cars had “conventional” ZDDP and the others had low volatility ZDDP both at a phosphorous concentration of around 0.75.
After the test period the O2 sensors showed no unusual deterioration. The catalytic systems were taken off the cars and tested for working efficiencies by Southwest Research Institute in San Antonio, TX.
Both oils maintained “excellent” antiwear and antioxidancy engine performance.
There was a 30 % reduction of deposits on the low volatility ZDDP cats.
Improved THC light off times.
NO emissions reduced 10 %.
CO emissions were lowered by 50 % after the forward cat and 15 % after the second cat.
(This means to me that there is much more reserve left in the system using the low vol ZDDP)
One car using the low volatility ZDDP but with the highest oil consumption showed no improvement over the regular ZDDP cars.
This is one study that seems to be well done and shows that both oil consumption and the use of high volatility ZDDP results in significantly higher catalyst deterioration. Note that there are multiple ZDDP formulations.
aehaas
