New Castrol 20w50 High Zinc oil (1 Viewer)

[Spike Strip]

Just an FYI for those concerned about proper flat tappet engine oil and don't like the idea of $120 oil changes.

Not intended as a thread for 'What oil/filter you use, and it's been fine..."

Castrol has re-introduced an old SJ rated oil for classic cars. 1400 ppm zddp. $25 per 5/gal jug at Wally world.

Notice no API star burst cuz of the old spec.

CASTROL GTX CLASSIC | WELCOME | CASTROL USA

Castrol® GTX® Classic is a high zinc formula providing extreme protection for your hot rod or classic car and high output engines with performance cams. Treat your flat tappet or push rod engine right with this authentic 20w-50 engine oil.

www.castrol.com

 

[DesertFJ40]

Cool, good to know. The valvoline 20w50 has just gotten too stupid expensive. 1400 seems to be what most zinc "rich" oils hover around now..... And, the heavier weight oil makes my engine pur compared to 15w40. I was able to notice a difference in noise.

 

[Spike Strip]

Most High-Zinc oils, unless a boutique oil like Brad Penn or Amzoil or Lucas, are around 1000 -1300, advertised. As most are SN or other modern rated, so they're limited by definition on the amt of Zinc they can have. Notice the Castrol bottle says 'Don't use with a CAT' cuz it will shorten the life and no API or SAE rating.

Ideal would be around 1600 ppm for a 5K mile OCI, but the 1400 ppm is good if you like to change frequently, say 3-5K miles as that's about where the zddp has been consumed and will get to unhealthy levels for a flat-tappet antique engine.

The price is nice, too. You could always add a couple of qts of VR1 if you wanted to bump up the concentration and add some synthetic oomph to it.

I believe this is the stuff Castrol has sold in the UK for a long time and has now brought to the States. Only available here, though, as a 20w50

I want one of those oil cans....

Castrol Classic Oils | company homepage | for vehicles 1900-1990s

At Castrol Classic Oils, we provide the ultimate in protection for all veteran, vintage and classic car and motorcycle owners. For vehicles from the 1900's-1990's, mineral oils produced to the original viscosities with the correct anti-wear additives.

www.classicoils.co.uk

 

[middlecalf]

Where did you find the zddp level? And is it a combined value of zinc and phosphorus?

 

[Spike Strip]

Castrol advertised as 1400 ppm zinc and VOA on BITOG confirmed. Phos was around 1300 ppm. Decent detergent pkg, too. Plus, it's a SJ rated oil ONLY, so by definition has to be between 1400-1700 ppm? 1980s vintage. Would make sense they just hit the lower limit.

 

[middlecalf]

So is that 2700 ppm zddp given your numbers for zinc and phosphorus? Can‘t find anywhere that discusses what the equation for zddp is other than its zinc and phosphorus combined. I ask because there are references to too much zddp causing corrosion, and as stated here and other posts the “good” amount of zddp is 1400-1600 ppm. Hence my question.

 

[rkymtnflyfisher]

Could be interesting, maybe I'll get lucky and my localish wallyworld will have it. I wonder what the impact of 0F temps would be on that, nothing le pumping honey on the way to the mountains.

 

[rkymtnflyfisher]

Quick Google-fu says that 0F is right at the bottom of the temp range on that.


I'd be good for July.

 

[Spike Strip]

I wouldn't run this 20w50 in temps that cold. For me it's fine in Lost Angeles and So Cal ... for cold weather winters I'd be more inclined to run a synthetic or Semi-syn like a Rotella T5 with maybe a qt or two of VR 1 to bump it up a little. Castrol in warmer months. But if you warm up the truck to op temp before starting, it's fine.

ZDDP is a compound of zinc and Phos. The 1440 ppm is a those two elements combined. The numbers get confusing. Safe is no more that 2500 ppm zddp depending on how hard you run the motor, i.e. race applications or snow plowing etc. For every day and off road, 1700ppm for 5K OCI seems to be the sweet spot - Right were it used to be before the wackos took over.

 

[sokoloka]

Have been running this alongside VR1 in several of my clunkers over about the past year and the 20w-50 combo is perfect out here in San Diego. Not getting anywhere close to the mileage intervals but done a few changes with it and all's smoothing running so far.

Burn it faster than I can hit the mileage intervals

 

[middlecalf]

Based on what I see (and sort of understand) Rotella T4 (dino) and Rotella T5 (syn blend) are in this range of zddp if wanting a bit lower viscosity (15w-40). Just need a 10w-30 variant .

 

[Spike Strip]

Yes, the T5 is good stuff and for whatever reason has higher zddp than T4, around 1300 last I looked, for the 15w40

 

[DuckBone]

What’s the consensus for running high zinc oils for those of us with Cruisers blessed (cursed) with factory catalytic converters?

 

[rainingagain]

What’s the consensus for running high zinc oils for those of us with Cruisers blessed (cursed) with factory catalytic converters?

I've noodled on this myself. I have a 79 F100. It has a cat and flat tappet lifters.

I've landed on the fact that it ran on oil that had zinc in it for 20 years before I got it. Same original cat. No issues. I can only assume this is a very basic cat converter that can handle zinc ash that gets through. But I don't put a lot of miles on it. Highway miles anyway. But I still run an oil with zinc.

Interesting question.

 

[Spike Strip]

Newer CATs have a very thin wash of precious metals that don't handle zinc compounds as well as older and more robust units. However, I go by the truism that CAT converters are way cheaper than engine work or rebuild even in Kalifornia.

 

[Racer65]

I'm late to the party and have been catching onto this topic. Didn't realize I could be running my Cruiser engine to the ground if I don't pay attention!
For those who may be newer to the topic (like me) here's a quick recap:

• In recent years oil manufacturers have been reducing the level of zinc and phosphorous, also known as ZDDP.
• Older engines with flat tappets (like Cruiser engines) need ZDDP to protect cam and tappet wear.
• Newer engines with roller cams don't need much ZDDP protection, therefore manufacturers have been dropping ZDDP levels.
• Engine oils now typically have ZDDP level in the 800 ppm range. Anything below 1000 ppm is likely to cause wear on flat tappet engines.
• The issue of lowered ZDDP isn't a matter of synthetic vs dino oil. It's across the board.
• ZDDP level that's too high will damage catalytic converters from the blow-by

ZDDP content is normally not shown on the oil bottle. You literally have to Google for the data sheet!
Here are some that I've dug up:

• Mobile 1 10W-30: 830 ppm
• Mobile 1 High Mileage 10-30 / 10W-40: 870 ppm
• Mobile 1 FS 0W-40: 1100 ppm
• Mobile 1 FS X2 5W-40 / 5W-50: 1100 ppm
• Castro GTX Classic 20W-50: 1400 ppm (per Amazon listing)
• Shell Rotella T4 15W-40: 1203 ppm (listed as diesel oil)
• Shell Rotella T5 Synthetic Blend: 1267 ppm (listed as diesel oil)

Additional findings:

• You can use ZDDP additives to bring up the ZDDP level in your existing oil.
  • Be very careful about the amount of ZDDP these bottles will add, as too much ZDDP can cause problems.
  • All of these products put in a disclaimer that this product is for pre-cat engines.
  • If you pour in the whole bottle, you'll generally increase ZDDP to over 2000 ppm, which will knock out your cat.
  • Using such additive will most likely invalidate the warranty given by the oil manufacturer
• There are certain racing oils that contain high ZDDP levels. Do not use such oils on a street engine. Racing oils don't contain the necessary detergents for street use.

My conclusions?

• I live in California and my vehicle has a California cat. The choice must attend to protecting both the engine and the cat. Some say the EGR system may be affected as well, but I don't have solid information on that.
• I would choose an oil with ZDDP in the low 1000 ppm range, most likely one of the Mobile 1s with 1100 ppm.
• I wouldn't use a ZDDP additive, as I would rather have the oil company formulate the oil than to be my own chemist.
• I'd pay attention to the choice of viscosity based on where you operate. I came across a post (in a non Cruiser forum) saying that 5W-50 yielded too much oil pressure.

 

[Spike Strip]

My conclusions?

• 
  
• I would choose an oil with ZDDP in the low 1000 ppm range, most likely one of the Mobile 1s with 1100 ppm.

The only problem with a ZDDP level below 1200 ppm is ZDDP (and other additives) are consumed as the oil does its thing. After 3000 miles, you're around 800 ppm zddp remaining, or lower, depending on how you drive. Oils with that initial level of anti-wear zinc will need more frequent oil changes. That's why the sweet spot is 1400-1700 ppm with 3-5K mile oil change intervals, depending on how hard you are on the oil and climate. That generally keeps you in the safe zone for flat-tappet protection with normal driving.

I've been using the Castrol Classic and adding a quart of high zinc racing oil to pop it up a bit and change once or twice a year depending on how much mileage I put on the rig.

 

[Racer65]

The only problem with a ZDDP level below 1200 ppm is ZDDP (and other additives) are consumed as the oil does its thing. After 3000 miles, you're around 800 ppm zddp remaining, or lower, depending on how you drive. Oils with that initial level of anti-wear zinc will need more frequent oil changes. That's why the sweet spot is 1400-1700 ppm with 3-5K mile oil change intervals, depending on how hard you are on the oil and climate. That generally keeps you in the safe zone for flat-tappet protection with normal driving.

I've been using the Castrol Classic and adding a quart of high zinc racing oil to pop it up a bit and change once or twice a year depending on how much mileage I put on the rig.

Do you run a cat?

 

[robnicko]

Here in Aus we are lucky to have Penrite oils. Ive been using their HPR30 (20w/60) in my 80 series since new and its got a high Zinc formula @ 1600.
Not sure if its sold in the US but if it is you should try it. mines nearing 540,000kms & going very strong

 

[Spike Strip]

Do you run a cat?

Absolutely. I put a CAT even on my pre CAT LCs to cut down the stink. I know CA Catalytic converters are now around $1200 for a CARB compliant one, but still cheaper than engine repair.

The Rotella is excellent oil and will be easier on your CAT, just wouldn't go past 3K miles on it.

Btw, when zddp was plentiful in oil, CATs were expected to last 100K miles. Now they want them to last 150k with lower emissions.

I'm not worried about it.