QS Defy vs HDEO in old V8's

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I maintain a few carbureted pusherod flat tappet V8 engines. I have been using 10W30 HDEO (currently Rotella) for many years now with decent success. Would it be worthwhile to consider switching to QS Defy oil? Is there any benefit to using this oil over over an HDEO?

Opinions?
 
Slightly Better flow in cold weather maybe maybe 1% better gas milage. I would continue to use the HDEO. I have Delo 400 in my Regal and it loves it.
 
Defy could provide some protection against leaks. Mobil 1 High Mileage would too. Both have higher levels of ZDDP for your older vehicles.

If that's not a concern, stick with HDEO or VR1.
 
Horses for courses.
Depends upon what you're aiming to do.
In a leaker, Maxlife is far better than Defy in my actual experience.
Defy does have what I'd consider a nicer add pack on paper and does have API SL levels of ZDDP for those engines that really need it, although most of these engines did just fine back in the day on oils with no or low zinc.
A HDEO 10W-30 would click all of the wear boxes but none of the leak ones.
In a fairly oil-tight engine, either a HDEO 10W-30 or maybe 10W-40 Defy, although I'd favor Defy for no special reason.
In a leaker, Maxlife, although some have also reported good leak reduction with PHM.
JMHO.
 
I like Defy but for that use I'd probably lean towards Rotella. It would be my suspicion the Rotella might do better with the fuel dilution from the carb than Defy would.

Certainly won't hurt anything to try the Defy and see what you think.
 
Just curious KC, why do you think Defy wouldn't handle the carb's fuel dilution as well as Rotella? I thought that was one of the reasons for a high mileage oil being thicker for grade.
 
Diesel oil will handle contaminants better than a PCMO will IMO, it is intended for a nasty sooty diesel after all.

Not all HM oils are thick for grade anymore but Defy is and it is very good stuff no doubt. Run it and do a UOA, see what you get, would be interesting.
 
I know Castrol has changed their HM 5W-20 through 10W-30 to resource conserving, which doesn't make sense to me. I thought the high VI's in a "traditional" high mileage oil would stand up better to fuel dilution in carb'd and DI engines than standard conventional oils. I agree that HM probably wont handle soot, but as far as carb'd fuel dilution, I think Defy would be a perfect fit.
 
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I don't understand the Castrol thing either. They switched to Resource Conserving at least two years ago, maybe more, but there recent spec sheet update still shows it to be among the highest kinematic viscosity HM oils available.

I don't know how they do it, or maybe they didn't and they have something messed up. I have used a LOT of Castrol HM and it always has performed great.
 
Thanks for all the input. I will likely just stick with HDEO at this point. I may considering trying Defy if it goes on sale on the one SBC I maintain since its valve seals are starting to dry out, but I won't be hoping for any miracles.
 
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Defy never slowed down any leaks in my sons car but when I switched to PYB HM they pretty much went away after 2K miles. I then added a can of motor oil saver and the car does not leak at all... Runs very smooth and quiet.
 
Originally Posted By: Oldswagon
I maintain a few carbureted pusherod flat tappet V8 engines. I have been using 10W30 HDEO (currently Rotella) for many years now with decent success. Would it be worthwhile to consider switching to QS Defy oil? Is there any benefit to using this oil over over an HDEO?

Opinions?


Oldswagon,

We would recommend using two different products- QS Defy 10W30 Synthetic Blend Motor Oil or Rotella HDEO products. QS Defy 10W30 Synthetic Blend Motor Oil is specifically formulated with extra-wear additives to help reduce wear on worn engine parts, as well as extra protection for those flat tappets. It also has an increased amount of seal conditioners to help reduce oil leakage, which is something the Rotella 10W30 HDEO product would not necessarily have.

The Rotella HDEO products are indeed a good choice for this application as well. You also might want to consider the Shell Rotella T5 10W-30 semi-synthetic product because it is formulated with higher zinc wear package for those flat tappets.

-The Shell Rotella Team
 
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