XfireZ51
04-05-2009, 03:54 PM
Did some searching this afternoon and came up with a possible alternative for addressing the lack of zinc phosphate. I have used Castrol GTX for many years with very good results on my 84 flat tappet motor. Later I replaced it with a roller.
But here's some interesting information:
http://www.castrol.com/liveassets/bp_internet/castrol/castrol_usa/STAGING/local_assets/downloads/p,q/pds_GTX_Diesel.pdf
You'll note the excellent levels of Zinc and Phosphorous in the Diesel Motor Oil.
Also someone got an answer from Castrol on the issue of zinc in the oil. This is from the International 190SL Forum member bertfan
bertfam
02-08-2007, 12:37 PM
I contacted Castrol with this question and here's their answer:
Castrol is aware of articles in enthusiast magazines and web-sites, as well as after-market parts manufacturer discussions concerning GF-4 engine oils and cam-shaft durability issues in older performance vehicles. Some consumers suspect the lower level of ZDDP in GF-4 oils may be causing these failures. Castrol is currently investigating this issue.
As indicated on our product packaging, the current engine oil category API SM/ILSAC GF-4 is fully backwards compatible or 'back serviceable' and has been extensively tested. Valve train issues are not anticipated with the use of modern engine oil in older cars of OEM stock configuration. In fact, current SM/GF-4 engine oils are subjected to testing that is far more intensive than engine oils of previous API/ILSAC categories.
To clarify, in general, ZDDP levels have been reduced a small amount in the current category engine oils (API SM/ILSAC GF-4) in compliance with industry regulations that set maximum levels of Sulphur and Phosphorus, but are still at levels that provide ample engine protection.
Special procedures have always been recommended for the proper initial break-in of a new, matched, cam and lifter set; which include the use of a properly formulated cam break-in lubricant paste which typically contains a healthy dose of molybdenum. Engine oil alone is typically insufficient for break-in of a new cam and lifter set, particularly in a vintage engine type built to historic specifications.
For those consumers that wish not to use a GF-4 oil in these vehicles, Castrol does offer the following products that contain Zinc at a level that is higher than the Zinc level found in oils (API SG) marketed during the "muscle car" era of time:
* Castrol GTX 20W-50 (SL,SM)
* Castrol GTX Diesel 15W-40 (CI4,CH4,CG4,CF4,CF,SL)
* Castrol GTX High Mileage 20W-50 (SL,SM)
* Castrol HD 30 (SL,SM)
* Castrol HD 40 (SL,SM)
* Castrol Syntec Blend Truck 15W-40 (CI4,CH4,CG4,CF4,CF,SL)(Semi-synthetic)
* Castrol Tection Extra 15W-40 (CI4Plus, CI4,CH4,CG4,CF4,SL)
* Castrol Hypuron S 15W-40 (CI4Plus,CH4,CG4,SL)(Semi-synthetic)
The following Castrol products have Zinc levels that are typical of API SG
oil:
* Castrol Syntec 5W-40 (SL,CF)(Synthetic)
* Castrol GO! 10W-40 Motorcycle Oil (SG)
* Castrol GO! 20W-50 Motorcycle Oil (SG)
* Castrol Grand Prix 4-Stroke Motorcycle Oil 10W-40 (SG)
* Castrol Grand Prix 4-Stroke Motorcycle Oil 20W-50 (SG)
* Castrol TWS Motorsport 10W-60 (SJ)(Synthetic)
If installing a new performance cam in an older performance vehicle, it is important to:
* follow the installation recommendations provided by the cam manufacturer
* use the recommended cam break-in lube
* prime the engine oil circuits
* use the recommended engine oil
*confirm valvetrain geometries prior to starting the engine with the new cam
Ed
But here's some interesting information:
http://www.castrol.com/liveassets/bp_internet/castrol/castrol_usa/STAGING/local_assets/downloads/p,q/pds_GTX_Diesel.pdf
You'll note the excellent levels of Zinc and Phosphorous in the Diesel Motor Oil.
Also someone got an answer from Castrol on the issue of zinc in the oil. This is from the International 190SL Forum member bertfan
bertfam
02-08-2007, 12:37 PM
I contacted Castrol with this question and here's their answer:
Castrol is aware of articles in enthusiast magazines and web-sites, as well as after-market parts manufacturer discussions concerning GF-4 engine oils and cam-shaft durability issues in older performance vehicles. Some consumers suspect the lower level of ZDDP in GF-4 oils may be causing these failures. Castrol is currently investigating this issue.
As indicated on our product packaging, the current engine oil category API SM/ILSAC GF-4 is fully backwards compatible or 'back serviceable' and has been extensively tested. Valve train issues are not anticipated with the use of modern engine oil in older cars of OEM stock configuration. In fact, current SM/GF-4 engine oils are subjected to testing that is far more intensive than engine oils of previous API/ILSAC categories.
To clarify, in general, ZDDP levels have been reduced a small amount in the current category engine oils (API SM/ILSAC GF-4) in compliance with industry regulations that set maximum levels of Sulphur and Phosphorus, but are still at levels that provide ample engine protection.
Special procedures have always been recommended for the proper initial break-in of a new, matched, cam and lifter set; which include the use of a properly formulated cam break-in lubricant paste which typically contains a healthy dose of molybdenum. Engine oil alone is typically insufficient for break-in of a new cam and lifter set, particularly in a vintage engine type built to historic specifications.
For those consumers that wish not to use a GF-4 oil in these vehicles, Castrol does offer the following products that contain Zinc at a level that is higher than the Zinc level found in oils (API SG) marketed during the "muscle car" era of time:
* Castrol GTX 20W-50 (SL,SM)
* Castrol GTX Diesel 15W-40 (CI4,CH4,CG4,CF4,CF,SL)
* Castrol GTX High Mileage 20W-50 (SL,SM)
* Castrol HD 30 (SL,SM)
* Castrol HD 40 (SL,SM)
* Castrol Syntec Blend Truck 15W-40 (CI4,CH4,CG4,CF4,CF,SL)(Semi-synthetic)
* Castrol Tection Extra 15W-40 (CI4Plus, CI4,CH4,CG4,CF4,SL)
* Castrol Hypuron S 15W-40 (CI4Plus,CH4,CG4,SL)(Semi-synthetic)
The following Castrol products have Zinc levels that are typical of API SG
oil:
* Castrol Syntec 5W-40 (SL,CF)(Synthetic)
* Castrol GO! 10W-40 Motorcycle Oil (SG)
* Castrol GO! 20W-50 Motorcycle Oil (SG)
* Castrol Grand Prix 4-Stroke Motorcycle Oil 10W-40 (SG)
* Castrol Grand Prix 4-Stroke Motorcycle Oil 20W-50 (SG)
* Castrol TWS Motorsport 10W-60 (SJ)(Synthetic)
If installing a new performance cam in an older performance vehicle, it is important to:
* follow the installation recommendations provided by the cam manufacturer
* use the recommended cam break-in lube
* prime the engine oil circuits
* use the recommended engine oil
*confirm valvetrain geometries prior to starting the engine with the new cam
Ed