Zinc additive, which one?

[bklyn]

Last week I posted that for some reason it was getting harder to find Brad Penn oil in my area. So if I do not mail order it and use, lets say Castrol 20-50 what would be a good zinc additive that is not snake oil?

[Aurel]

There are other choices of oil with ZDDP. I use Kendall GT1 from Autozone for example.

[Bill Verburg]

Here are Kendalls specs for their Gt1 oils
T-1® High Performance Motor Oil
Typical Properties
SAE Grade 10W-40 20W-50
Density, g/cm3 @ 15.6°C (60°F) 0.873 0.883
Density, lbs/gal @ 15.6°C (60°F) 7.27 7.35
Color, ASTM D1500 3.0 3.5
Flash Point (COC), °C (°F) 227 (441) 230 (446)
Pour Point, °C (°F) -33 (-27) -30 (-22)
Viscosity,
cSt @ 40°C 108 175
cSt @ 100°C 15.3 18.6
SUS @ 100°F 559 913
SUS @ 210°F 81.9 94.9
Viscosity Index 150 120
Cold Cranking Viscosity, cP 6,600 6,600
@ (°C) (-25) (-15)
High-Temp/High-Shear Viscosity, cP @ 150°C 3.9 4.8
Sulfated Ash, ASTM D874, wt % 0.94 0.98
Total Base Number (TBN), ASTM D2896 7.8 7.8
Phosphorus, wt % 0.077 0.108
Zinc, wt % 0.085 0.119

translation for 10w-50 phosphorus 1080ppm, zinc 1190ppm

as noted previously oils that do not have to meet ILSAC GF-4 standards will have more of these 2 ingredients

there are others for instance in Mobil 1 the zinc & phosphorus content is in the range of 0.12 - 0.13 weight percent (1200 - 1300 ppm)
M1 product guide

if you want really high levels of zinc/phosphorus you would need to use a racing oil, M1 racing is 1750-1850 ppm Swepco, Brad Penn, Joe Gibbs have similar racing products.

there are all sorts of additives from Eastwood to STP , but using an acceptable base oil is best, in the 110ppm range is generally considered adequate

[DanielDudley]

Several 911 mechanics are passionately against Castrol on this board.

Valvoline VR1 racing is also a good oil with decent ZDDP levels.

[JFairman]

This is one of the best if not the best... It's also the only one I've seen that's made with synthetic oil and thats a good in a hot turbo.

Accordding to the specs on the webpage half a bottle mixed with 12 quarts of Valvoline VR1 would give you around the same amount of zddp as Brad Penn racing oil.

Red Line Synthetic Oil - Motor Oil for Racing - Engine Oil Break-In Additive

[nineball]

Originally Posted by DanielDudley

Valvoline VR1 racing is also a good oil with decent ZDDP levels.

i second that. last year it was on sale for 50% off and now i have 7 cases sitting in the garage

[tcar]

NAPA here has ZDDP additive. Use w/ Mobil 1.

...or Christopher Hitchens on Stieg Larsson | Culture | Vanity Fair

you need 2 bottles per oil change.

You can also get Brad Penn on ebay pretty reasonably.

[bklyn]

Thanks for the new ideas, found Brad Penn on e-bay, not a bad price but shipping is a killer.

[914efi]

I've looked at all the oil brands mentioned and they are all SM, I thought this grade was low on ZDDP. The higher weight oils still say SM even though supposedly the low ZN and P are only req'd for lower weight oils? After all the reading, still not really sure what to buy! IS GF-4 the real designation to look for?

I have some Joe Gibbs (expensive) and 'Kenwood' that I found at a local mini chain (Benny's) that is SL.

Sorry in advance if this is a hijack or re-hash. I have to feed a 911, MGB, 944 and 6cyl Bronco.

[70SC]

Just changed out my oil from Castrol GTX 20/50 to Brad Penn 20/50 Car is smoother with less valve train noise . B P is getting harder to find , But IMHO is definitely worth it !!!!!!!! My car didn't like the Castrol , It's much happier with it's fresh blood . And NO need to mess with expensive additives . BP Rocks

[HarryD]

For those looking to doctor a lesser oil, I have 5 bottles of the old GM EOS that I would be willing to part with. E-mail me and we can make a deal.