Because it was spec'd for an oil with higher ZDDP levels and hdeo is the closest match.
What brand of 10w30 should I use in classic car
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The above choices are great, but I guaranty your cam and lifter bottoms are worn [even with the old higher zinc oils there was always wear].
New Recommendation after seeing where your located. Shell Rotella T5 10w-30 for October thru March, and Shell Rotella 1 HD30 or any other Diesel HD30 for April thru September is what I would use.
Valvoline Maxlife 5W-30
Originally Posted By: electrolover
Because it was spec'd for an oil with higher ZDDP levels and hdeo is the closest match.
Not any more now that we have a PCMO specifically blended for older cars.
Because it was spec'd for an oil with higher ZDDP levels and hdeo is the closest match.
Not any more now that we have a PCMO specifically blended for older cars.
With 125K on a 46 year old 400 CI engine, a contemporary oil with a 3.5 HTHS could be preferable over the originally spec'd oil. In fact, the 10W30 or straight 30W oils recommended way back then just might have been 3.5 HTHS, or higher.
Different strokes for different folks......we much prefer the Amsoil synthetics
or anything QS.
Different strokes for different folks......we much prefer the Amsoil synthetics
or anything QS.
Yep, Quaker State Green Bottle HD30 sounds just about Right.
Thanks for your recommendation. I visited the AMSOIL site and read the info on their oil designed for classic cars. I have always used mineral oil for 46 years and never tried a synthetic. Their Z Rod 10w30 is formulated for cars like mine w/o a catalytic converter. Having said that, AMSOIL must feel that an old car that was never run on synthetic oil must be OK to switch to synthetic. My car was never raced, modifed, or hot rodded. I drive it about 700 miles a year. Many responders recommended Rotella T. I am just a little hesitant to use an oil designed for trucks. Likewise, racing oils for a car that is not raced may not be the way to go. AMSOIL has the ZDDP that the oils in the 60's and 70's had.
Use your favorite 10W30 with this. http://www.eastwood.com/ew-zddp-oil-additive-4-oz.html
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Rotella T5 10w-30 or Mag1 HD 10w-30
T6 would be a great choice, as well.
T6 would be a great choice, as well.
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Valvoline VR1 would be a good,cheap,and easily obtainable oil. It comes in 10W30,20W50,50,and 60.
Originally Posted By: CATERHAM
Originally Posted By: electrolover
Because it was spec'd for an oil with higher ZDDP levels and hdeo is the closest match.
Not any more now that we have a PCMO specifically blended for older cars.
Modern high mileage PCMO only have a tad more ZDDP than regular passenger car oil and nowhere near what a flat tappet engine needs to survive. Modern oils are formulated for modern engines. "Older" HM oil means about 10 years or so.
Even the CJ-4 HDEO are down on ZDDP levels.
Moreover, 15w-40 is perfectly acceptable for the engine in question. Owners manuals then often included a chart indicating which oils could be used in particular temperature ranges, including 15w-40.
Originally Posted By: electrolover
Because it was spec'd for an oil with higher ZDDP levels and hdeo is the closest match.
Not any more now that we have a PCMO specifically blended for older cars.
Modern high mileage PCMO only have a tad more ZDDP than regular passenger car oil and nowhere near what a flat tappet engine needs to survive. Modern oils are formulated for modern engines. "Older" HM oil means about 10 years or so.
Even the CJ-4 HDEO are down on ZDDP levels.
Moreover, 15w-40 is perfectly acceptable for the engine in question. Owners manuals then often included a chart indicating which oils could be used in particular temperature ranges, including 15w-40.
Originally Posted By: Rock_Hudstone
Originally Posted By: CATERHAM
Originally Posted By: electrolover
Because it was spec'd for an oil with higher ZDDP levels and hdeo is the closest match.
Not any more now that we have a PCMO specifically blended for older cars.
Modern high mileage PCMO only have a tad more ZDDP than regular passenger car oil and nowhere near what a flat tappet engine needs to survive. Modern oils are formulated for modern engines. "Older" HM oil means about 10 years or so.
Even the CJ-4 HDEO are down on ZDDP levels.
Moreover, 15w-40 is perfectly acceptable for the engine in question. Owners manuals then often included a chart indicating which oils could be used in particular temperature ranges, including 15w-40.
Not really true if you believe Blackstone's analysis of vintage oils...
http://www.blackstone-labs.com/Newsletters/Gas-Diesel/June-1-2012.php
Originally Posted By: CATERHAM
Originally Posted By: electrolover
Because it was spec'd for an oil with higher ZDDP levels and hdeo is the closest match.
Not any more now that we have a PCMO specifically blended for older cars.
Modern high mileage PCMO only have a tad more ZDDP than regular passenger car oil and nowhere near what a flat tappet engine needs to survive. Modern oils are formulated for modern engines. "Older" HM oil means about 10 years or so.
Even the CJ-4 HDEO are down on ZDDP levels.
Moreover, 15w-40 is perfectly acceptable for the engine in question. Owners manuals then often included a chart indicating which oils could be used in particular temperature ranges, including 15w-40.
Not really true if you believe Blackstone's analysis of vintage oils...
http://www.blackstone-labs.com/Newsletters/Gas-Diesel/June-1-2012.php
Originally Posted By: Rock_Hudstone
Originally Posted By: CATERHAM
Originally Posted By: electrolover
Because it was spec'd for an oil with higher ZDDP levels and hdeo is the closest match.
Not any more now that we have a PCMO specifically blended for older cars.
Modern high mileage PCMO only have a tad more ZDDP than regular passenger car oil and nowhere near what a flat tappet engine needs to survive. Modern oils are formulated for modern engines. "Older" HM oil means about 10 years or so.
Even the CJ-4 HDEO are down on ZDDP levels.
Moreover, 15w-40 is perfectly acceptable for the engine in question. Owners manuals then often included a chart indicating which oils could be used in particular temperature ranges, including 15w-40.
That was a false statement, regarding ZDDP levels. The reason for higher ZDDP levels in the past was it was cheap and it was a suitable antioxidant in the long term too much ZDDP causes wear to increase.
Originally Posted By: CATERHAM
Originally Posted By: electrolover
Because it was spec'd for an oil with higher ZDDP levels and hdeo is the closest match.
Not any more now that we have a PCMO specifically blended for older cars.
Modern high mileage PCMO only have a tad more ZDDP than regular passenger car oil and nowhere near what a flat tappet engine needs to survive. Modern oils are formulated for modern engines. "Older" HM oil means about 10 years or so.
Even the CJ-4 HDEO are down on ZDDP levels.
Moreover, 15w-40 is perfectly acceptable for the engine in question. Owners manuals then often included a chart indicating which oils could be used in particular temperature ranges, including 15w-40.
That was a false statement, regarding ZDDP levels. The reason for higher ZDDP levels in the past was it was cheap and it was a suitable antioxidant in the long term too much ZDDP causes wear to increase.
Originally Posted By: redgoat
Thanks for your recommendation. I visited the AMSOIL site and read the info on their oil designed for classic cars. I have always used mineral oil for 46 years and never tried a synthetic. Their Z Rod 10w30 is formulated for cars like mine w/o a catalytic converter. Having said that, AMSOIL must feel that an old car that was never run on synthetic oil must be OK to switch to synthetic. My car was never raced, modifed, or hot rodded. I drive it about 700 miles a year. Many responders recommended Rotella T. I am just a little hesitant to use an oil designed for trucks. Likewise, racing oils for a car that is not raced may not be the way to go. AMSOIL has the ZDDP that the oils in the 60's and 70's had.
I like the idea of QS Defy 5W30. I am using it in my '80 Firebird FORMULA V8(purchaced new) and really like it! Made the engine a bit smoother/quieter than I'd prefer for this engine but, most QS oils(QSUD/QSGB) also seem to do this in my other vehicles these days.
I have tried HDEO's and MaxLife in this Pontiac engine over the years and they're OK too! Any of the oils recomended for your GTO will be fine...You pick! It doesn't seem as though you're driving the car hard; sounds like you're just cruising!
My buddy completed his '61 Corvette restoration about 10 years ago with a 350 GM crate motor and has never used any special oil except for Castrol(GTX), Pennzoil(PYB) or Valvoline(VWB) conventional 10W30. I have mentioned to him about the lesser amount of ZINC in todays oils. He doesn't seemed concerned!
He doesn't drive this car hard either(although he may drive it quickly/swiftly), AND the exception of a quick WOT, now & again on the way to a car show... That's nott'in!
Thanks for your recommendation. I visited the AMSOIL site and read the info on their oil designed for classic cars. I have always used mineral oil for 46 years and never tried a synthetic. Their Z Rod 10w30 is formulated for cars like mine w/o a catalytic converter. Having said that, AMSOIL must feel that an old car that was never run on synthetic oil must be OK to switch to synthetic. My car was never raced, modifed, or hot rodded. I drive it about 700 miles a year. Many responders recommended Rotella T. I am just a little hesitant to use an oil designed for trucks. Likewise, racing oils for a car that is not raced may not be the way to go. AMSOIL has the ZDDP that the oils in the 60's and 70's had.
I like the idea of QS Defy 5W30. I am using it in my '80 Firebird FORMULA V8(purchaced new) and really like it! Made the engine a bit smoother/quieter than I'd prefer for this engine but, most QS oils(QSUD/QSGB) also seem to do this in my other vehicles these days.
I have tried HDEO's and MaxLife in this Pontiac engine over the years and they're OK too! Any of the oils recomended for your GTO will be fine...You pick! It doesn't seem as though you're driving the car hard; sounds like you're just cruising!
My buddy completed his '61 Corvette restoration about 10 years ago with a 350 GM crate motor and has never used any special oil except for Castrol(GTX), Pennzoil(PYB) or Valvoline(VWB) conventional 10W30. I have mentioned to him about the lesser amount of ZINC in todays oils. He doesn't seemed concerned!
He doesn't drive this car hard either(although he may drive it quickly/swiftly), AND the exception of a quick WOT, now & again on the way to a car show... That's nott'in!
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I'm with dave1251. I think too much stock is put in ZDDP these days. There are other adds that don't show up as metals doing the work now, while keeping the ash levels down. This has to be a plus, especially for a unit that uses some oil. The newer oils are backward compatible for older applications.
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Originally Posted By: dave1251
The reason for higher ZDDP levels in the past was it was cheap and it was a suitable antioxidant in the long term too much ZDDP causes wear to increase.
And we do have to remember that in the days of no limits on ZDDP, that doesn't mean all the oils had high ZDDP, either. Plenty of old VOAs we've seen show ZDDP at about current levels. We see the same with 40 and 50 grades. They don't have the same limitations; that doesn't mean they have a lot, either.
VR1 or Defy would be great options, as would an HDEO. VR1 would be one of my favourite choices, but it's a little expensive up here.
The reason for higher ZDDP levels in the past was it was cheap and it was a suitable antioxidant in the long term too much ZDDP causes wear to increase.
And we do have to remember that in the days of no limits on ZDDP, that doesn't mean all the oils had high ZDDP, either. Plenty of old VOAs we've seen show ZDDP at about current levels. We see the same with 40 and 50 grades. They don't have the same limitations; that doesn't mean they have a lot, either.
VR1 or Defy would be great options, as would an HDEO. VR1 would be one of my favourite choices, but it's a little expensive up here.
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