

⚙️ Protect your legacy engine like a pro—because classics deserve premium care!
ZDDP Maxx is a high-performance zinc and phosphorus oil additive designed to restore and maintain optimal protection for pre-1990 gasoline and pre-2007 diesel engines. Compatible with all API SM oils and gear oils, it delivers precise dosing for racing and break-in applications, ensuring reduced wear and extended engine life. With a strong 4.7-star rating and free shipping, it’s the trusted choice for vintage and performance engine enthusiasts.
| ASIN | B003MAG004 |
| Brand | zddp Maxx |
| Customer Reviews | 4.7 4.7 out of 5 stars (56) |
| Date First Available | May 16, 2010 |
| Item Weight | 3 ounces |
| Item model number | 4oz |
| Manufacturer | zddp maxx |
| Manufacturer Part Number | 891906002058 |
C**F
Nice product
I added this to my 1938 streetrod. SB pre 1975 Chevy V* and I was told that the valves needed a zinc additive. Price was good and I guess it is working, wont know until I tear it down which won't be far a couple of years. Unless something goes wrong..
D**E
Good Value - Easy to store
Since it's an additive there is no way to know the effectiveness. It gives me peace of mind knowing my older 454 Chevy is getting the zinc and phosphorus it needs.
J**E
Shipped fast bittle was tiny 2oz for the money will ...
Shipped fast bittle was tiny 2oz for the money will never buy again for same price can get big bortle and have enough to do more than one oil change
G**E
GM Lifter CLACK GONE!!!
35 years in the automotive aftermarket, and I'm no fool. I have an 05' Tahoe 5.3L with Chevy lifter tick that is the worst I have ever heard. I pulled the valve covers, cleaned the pushrods, and lifters. Replace a few rockers thinking that was the problem. I tried flushing multiple times because I refuse to pull these heads with close to 200,000 miles. Sometimes it CLACK's Hot sometime Cold, but always CLACKS.. I Tried, Seafoam, Rislone, Marvel mystery oil... After reading a service bulletin from GM, I purchased GM Enos, with 12,000ppm zinc and it helped after a few days.. but the fact that it helped little gave me hope. I tried the Crane Cams assembly lube because it supposedly has more zinc that the others but that didn't help at all.. Eventually, I timed it right, and got my ZDDP when I was ready to change the oil. At first, it sounded the same.. CLACK CLACK CLACK.. after a few days, (about 450 miles) it was only CLACKING after about 30 minutes of driving... About 10 days in.. SILENCE! I swear SILENCE. 150+ miles a day 4 to 4.5 hours in LA traffic daily. I drove it from LA to Seattle this summer.. SILENCE. I will even drive it to SEMA again this year.. The engineer I work with asked me when I fixed the truck, I laughed and told him the truth. I am due for another oil change, and my new bottle showed up yesterday! I would ABSOLUTELY recommend this product.. its a winner
S**E
A must use for older engines
I use this product in my 1972 Ford with a 429 engine. The new oils have removed these additives to accommodate modern smog control systems. The older engines need these additives to protect the valve train and other parts. The older engines were designed to use oils with these additives. The protection is cheap and I'm happy to find a decent source.
#**4
Four Stars
works good
C**N
Older engines NEED this
Everything was better in the good ol' days-- rock and roll, non-ethanol gasoline, action movies, and even motor oil had more good stuff in it to keep things moving. If you are driving a car with a flat-tappet engine (and if your car is older than about 1985, you most likely do), then adding zinc to your engine oil is important for reducing unnecessary wear to the valve train. I recenlty bought an '85 Nissan 720 pickup, and from the looks of it the previous owner wasn't too concerned about making the vehicle last. My first clue was the piece of bailing wire holding the choke open, but that's another story... Anyway, I changed the oil using a high-mileage conventional oil, and added ZDDP Maxx. The valves were quite a bit quieter afterwards, being properly lubricated for the first time since the Clinton administration. If you have an older engine, and you want it to last, read up about it online-- most likely, you need this product to be sure it is being lubricated as it was designed to be.
G**D
was surprise!!!
Great really worked well
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3 weeks ago
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