Just bought a 1964 GTO with about 4K on the rebuilt engine(389 3X2). Am looking at using Amsoil Z-Rod 20W-50 or 10W-40 in it for year-round use. What are your opinions on this oil and what other recommendation for an oil can you give me.
Muscle car Zinc oil
- Thread starter vwalburn
- Start date
- Status
Mobil 1 high mileage 10w40
I have several 1960's-70's cars. I researched the Zn levels of many oils that are certified for use in car engines. I narrowed it down to: Mobil 1 15w-50 1300 ppm Zn, Mobil 1 Turbo Diesel Truck 5w-40 (also certified for cars) 1300 ppm Zn, Mobil 1 FSX2 5w-50 1100 Zn, Mobil 1 FS 1100 Zn,
Quaker State Defy High Mileage Syn Blend 5w-30, 10w-30, 10w-40 1200 ppm Zn, Valvoline VR1 Conventional Racing 10w-30 1400 ppm Zn. The several oil companies I talked to said that anything over 1000 ppm Zn should be used with flat tappets and high valve spring pressures. For a variety of reasons I settled on Mobil 1 Turbo Diesel Truck 5w-40 for the rebuilt engines and Quaker State Defy High Mileage Syn Blend for the original engines that have not been rebuilt. I hope this helps.
Quaker State Defy High Mileage Syn Blend 5w-30, 10w-30, 10w-40 1200 ppm Zn, Valvoline VR1 Conventional Racing 10w-30 1400 ppm Zn. The several oil companies I talked to said that anything over 1000 ppm Zn should be used with flat tappets and high valve spring pressures. For a variety of reasons I settled on Mobil 1 Turbo Diesel Truck 5w-40 for the rebuilt engines and Quaker State Defy High Mileage Syn Blend for the original engines that have not been rebuilt. I hope this helps.
Valvoline VR-1 is a good quality and high zinc oil suitable for your application. That would be my pick.
Also since you are considering a 20W-50, have a look at this 2017 Used Oil Analysis of Castrol GTX 20W-50, it has a good add package with 1094 ppm Zinc. That is a good amount.
https://bobistheoilguy.com/forums/ubbthreads.php/topics/4325388/
Also since you are considering a 20W-50, have a look at this 2017 Used Oil Analysis of Castrol GTX 20W-50, it has a good add package with 1094 ppm Zinc. That is a good amount.
https://bobistheoilguy.com/forums/ubbthreads.php/topics/4325388/
Last edited:
Originally Posted By: Building3
I have several 1960's-70's cars. I researched the Zn levels of many oils that are certified for use in car engines. I narrowed it down to: Mobil 1 15w-50 1300 ppm Zn, Mobil 1 Turbo Diesel Truck 5w-40 (also certified for cars) 1300 ppm Zn, Mobil 1 FSX2 5w-50 1100 Zn, Mobil 1 FS 1100 Zn,
Quaker State Defy High Mileage Syn Blend 5w-30, 10w-30, Quaker State Defy High Mileage Syn Blend for the original engines that have not been rebuilt. I hope this helps.
Unfortunately, Defy High Mileage went to a SN grade rating a while back and the Zn levels are just as pathetic as other SN oils.
Also, I believe Mobil 15w-50 is SN grade now and ZN and P levels dropped quite a bit as well, so stock up on any SM grade bottles still on the shelves
I have several 1960's-70's cars. I researched the Zn levels of many oils that are certified for use in car engines. I narrowed it down to: Mobil 1 15w-50 1300 ppm Zn, Mobil 1 Turbo Diesel Truck 5w-40 (also certified for cars) 1300 ppm Zn, Mobil 1 FSX2 5w-50 1100 Zn, Mobil 1 FS 1100 Zn,
Quaker State Defy High Mileage Syn Blend 5w-30, 10w-30, Quaker State Defy High Mileage Syn Blend for the original engines that have not been rebuilt. I hope this helps.
Unfortunately, Defy High Mileage went to a SN grade rating a while back and the Zn levels are just as pathetic as other SN oils.
Also, I believe Mobil 15w-50 is SN grade now and ZN and P levels dropped quite a bit as well, so stock up on any SM grade bottles still on the shelves
MolaKule
Staff member
Originally Posted By: vwalburn
Just bought a 1964 GTO with about 4K on the rebuilt engine(389 3X2). Am looking at using Amsoil Z-Rod 20W-50 or 10W-40 in it for year-round use. What are your opinions on this oil and what other recommendation for an oil can you give me.
Was this engine brought back to specs or were some internal upgrades made?
Was it dynoed after rebuild?
I would use the Amsoil Z-Rod 10W-40 without hesitation.
Just bought a 1964 GTO with about 4K on the rebuilt engine(389 3X2). Am looking at using Amsoil Z-Rod 20W-50 or 10W-40 in it for year-round use. What are your opinions on this oil and what other recommendation for an oil can you give me.
Was this engine brought back to specs or were some internal upgrades made?
Was it dynoed after rebuild?
I would use the Amsoil Z-Rod 10W-40 without hesitation.
I have a 1965 and a 1968 GTO both with rebuilt engines. Both engines probably have around 5000 miles each on them, and both get Amsoil Z-Rod 10W-30. They are both rebuilt to completely stock specs, and GM originally called for 10W-30. No need really for anything heavier, in my opinion.
Don't forget about this option as well...
Schaeffer Supreme 7000™ Synthetic Plus 10W-30
High zinc, multi-grade, para-synthetic racing oil for use in high performance gasoline engines including those with flat tappet cams.
Schaeffer Supreme 7000™ Synthetic Plus 10W-30
High zinc, multi-grade, para-synthetic racing oil for use in high performance gasoline engines including those with flat tappet cams.
Your totally not gonna use a 0W40 I bet, but you should use Castrol Edge 0W40, Valvoline Synpower 0W40 or Pennzoil 0W40. Those are Porsche A40 approved oils and they have the zinc your looking for. Those Pontiac V8's take forever to get oil from pan to valve train. The oil will flow from the sump up through the push-rods to the rocker arms faster than a 10W40 or 20W50.
You will wipe your cam faster using a 20W50 than you would something that flows quick and the same thing with a 10W40 vs a 0W40.
My dad was a LeMans/GTO collector until the early 90's. Those old Pontiac V8's have a rope seal and I advise you don't let the engine sit too long without it being started or you can expect a rear main leak.
You will wipe your cam faster using a 20W50 than you would something that flows quick and the same thing with a 10W40 vs a 0W40.
My dad was a LeMans/GTO collector until the early 90's. Those old Pontiac V8's have a rope seal and I advise you don't let the engine sit too long without it being started or you can expect a rear main leak.
congrats on a very sweet ride! do you know if the engine was upgraded to roller lifters? if so, you really don't care about zinc. that being said, I highly recommend Amsoil Z; or VR1. (I've got VR1 in my built 408 right now.... )
If the engine has a roller cam you don't need a high zinc oil.
If it has a flat tappet cam Z-Rod is a great oil, ifmyou can get Valvoline VR1 10W-30 locally that would be cheaper and still perfectly good.
If it has a flat tappet cam Z-Rod is a great oil, ifmyou can get Valvoline VR1 10W-30 locally that would be cheaper and still perfectly good.
Originally Posted By: skyactiv
Your totally not gonna use a 0W40 I bet, but you should use Castrol Edge 0W40, Valvoline Synpower 0W40 or Pennzoil 0W40. Those are Porsche A40 approved oils and they have the zinc your looking for. Those Pontiac V8's take forever to get oil from pan to valve train. The oil will flow from the sump up through the push-rods to the rocker arms faster than a 10W40 or 20W50.
You will wipe your cam faster using a 20W50 than you would something that flows quick and the same thing with a 10W40 vs a 0W40.
My dad was a LeMans/GTO collector until the early 90's. Those old Pontiac V8's have a rope seal and I advise you don't let the engine sit too long without it being started or you can expect a rear main leak.
If temps are high enough he would not have to worry about using a 20W-50.
Your totally not gonna use a 0W40 I bet, but you should use Castrol Edge 0W40, Valvoline Synpower 0W40 or Pennzoil 0W40. Those are Porsche A40 approved oils and they have the zinc your looking for. Those Pontiac V8's take forever to get oil from pan to valve train. The oil will flow from the sump up through the push-rods to the rocker arms faster than a 10W40 or 20W50.
You will wipe your cam faster using a 20W50 than you would something that flows quick and the same thing with a 10W40 vs a 0W40.
My dad was a LeMans/GTO collector until the early 90's. Those old Pontiac V8's have a rope seal and I advise you don't let the engine sit too long without it being started or you can expect a rear main leak.
If temps are high enough he would not have to worry about using a 20W-50.
Amsoil Z-Rod is a good oil but if you want to save a lot of money then take a look at the Penn Grade 1 synthetic blends made by Brad Penn out of the old Kendall refinery in Bradford, PA. Good basestock and good doses of zinc and phosphorous.
posts question regarding a 64 GTO and doesn't post pics....
but for reals
if the engine was rebuilt using a stock valvetrain then I wouldn't worry about it as just about any 10w-30 will work fine.
I'm using up the rest of my Quaker state defy now and will probably go with whatever high mileage oil is on sale at Wal-mart once its gone.
X2 on the rope style rear main seals. The ones available today do not work like they used to because you cannot make anything using asbestos like the good ol days. Every rebuilt Buick V8 has a leaky rear seal that starts out small and eventually builds to a substantial flow. My car leaks literally like a sieve until the level gets to around 3.5 qts then stops.
The only known cure for this is a neoprene seal.
but for reals
if the engine was rebuilt using a stock valvetrain then I wouldn't worry about it as just about any 10w-30 will work fine.
I'm using up the rest of my Quaker state defy now and will probably go with whatever high mileage oil is on sale at Wal-mart once its gone.
X2 on the rope style rear main seals. The ones available today do not work like they used to because you cannot make anything using asbestos like the good ol days. Every rebuilt Buick V8 has a leaky rear seal that starts out small and eventually builds to a substantial flow. My car leaks literally like a sieve until the level gets to around 3.5 qts then stops.
The only known cure for this is a neoprene seal.
- Status
Similar threads
