Impressions with Syntec 5w-20

[Darryl]

'99 Dodge Dakota 56,000 miles (10w-30 specd by Dodge). I have been using Mobil 1 0w-30 for the last 10,000 miles, before that, Royal Purple 5/10w-30 from 800 miles new. This last batch was 50/50 M1 0w-20 & 0w-40 as I couldn't find 0w-30 anywhere. My motor has always sounded sort of "buzzy" and I thought this was the normal sound of the motor (3.9 V6 moderately modified). Since I changed the oil at 800 miles, I really had no reference point. With gas so crazy in So Cal (91 octane ) I thought I would try something different: Castrol Syntec 5w-20 and see if my MPG would increase. I do not care about Syntec being a group 3 and fake synthetic and all the other stuff that's said. I only have 320 miles on the Syntec 5w-20 and my motor sounds way different, just ALOT smoother with zero "buzz" at any rpm. I have read on this site about M1 causing more noise for some people, and I thought it was their imagination. I now stand corrected . By the way, on the same drive, going the same speed with the same weather, I got 20.8 mpg vs the 18.5 mpg that I have averaged forever. I know this is not very scientific (like a UOA) but never the less, my engine runs like I always thought it should. Even my wife noticed!!! Now thats saying something! Darryl

 

[G-MAN]

Here is the text of a PM I sent to Johnny and Patman back in February when I started the 5w20 Pennzoil "experiment" with my 99 300M. Expect a 3000 mile UOA on this oil sometime in June. After that I'll be doing a 3000 mile run with Pennzoil synthetic 5w20, courtesy of Johnny.

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I'm pretty "in tune" with my Chrysler 300M and the 3.5 HO motor in it. I know its sounds and I know its ever little vibration. And most importantly, I know how it feels. I can honestly tell you that this Pennzoil 5w20 is the only oil I've ever put in this car where I can actually hear and feel a difference. I don't know if you're familiar with the 3.2 and 3.5 Chrysler engines, but the PCM is programmed to immediately rev the engine to 1500 rpms (for just a split second) upon start up. I've never liked this "feature" but I've learned to live with it. With the 5w20, the engine only revs to about 1200 and settles down to a 750 rpm idle much faster. The engine is noticeably smoother at all speed ranges, too. This is rather remarkable since these engines are known for their "Lexus-like" level of smoothness to begin with. And finally, I can actually notice a "seat of the pants" increase in pep, especially when the engine is still cold and I'm trying to merge into traffic. I really do hope the 3000 mile wear numbers are good because from a totally subjective standpoint, I really like the way this oil "behaves" in my car.

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Note: The difference in idle speed at start up was a temporary fluke that didn't last. Everything else I observed has remained the same. In addition, I'm seeing approx a 2 mpg increase with 5w20 over the GC 0w30 that I was using before.

 

[Darryl]

G-Man II, I have been waiting for your UOA. Even though our motors are completely different in design, they do share one thing in common, they both are spec'd by Chrysler (Dodge) for 5/10w-30. After looking at all the consistantly good UOA's on the 5w-20's, I took the plunge. I noticed everything you did on my motor as well, but I thought it might be overload to some to say that it also helped in throttle response as well as a smoother, quieter running engine. I really hope your results prove that we can run a 5w-20 in a non Ford/Honda motor, and the sky really won't fall Darryl

 

[G-MAN]

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Originally posted by Darryl: Even though our motors are completely different in design, they do share one thing in common, they both are spec'd by Chrysler (Dodge) for 5/10w-30.

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Chrysler doesn't leave much wiggle room when it comes to the oil specs for the 3.5 HO: The manual says use 10w30, and 5w30 is only acceptable at temps below 0F. Chrysler is specifying 5w20 for the 3.7 V6 for 2005, and I thought maybe they would be going to 5w20 in the 3.5 as well. But when I went to the Chrysler dealer to check out the new 300, they had a 300 Touring model that has the same 3.5 as my 300M in it and the oil cap was clearly marked "Use 10w30 Oil." 10w30 is not actually specified on my oil cap, just the API Starburst logo, so Chrysler must be pretty serious about 10w30 for the 3.5. Given how good my 3.5 "feels" on 5w20, I can't imagine that there is some design feature of this engine that mandates 10w30 in leiu of all other grades. Of course, my opinion will change if the wear numbers come back bad after 3000 miles on 5w20.

 

[DSteven]

Doesn't the 3.5 have direct acting tappets? I think Chrysler specs that oil to keep a good hydrodynamic bearing film for them at hot idle situations. I think it is really neat the 5W-20 is working well for you! It will be interesting to see the UOA results. I hope they are good, as I will be enticed to try it, too.

 

[ZiTS]

I put the Syntec 5w-20 in my Focus last oil change. Presently, it has around 1,000 miles on it (the oil, not the vehicle mileage). Since it takes me so long to rack up the miles, I'll probably be doing a UOA in the next month, just to see how it's looking.

 

[G-MAN]

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Originally posted by DSteven: Doesn't the 3.5 have direct acting tappets?

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No. The 3.2 and 3.5 are SOHC 24 valve engines that use rocker arms and roller tappets.

 

[ToyotaNSaturn]

G-Man, I'm curious to see if M1 0w-20 or 0w-30 would provide the same benefits as the Pennzoil 5w-20. GC seems a bit on the thick side where as this M1 would be thinner and aid in gaining MPG.

 

[G-MAN]

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Originally posted by ToyotaNSaturn: G-Man, I'm curious to see if M1 0w-20 or 0w-30 would provide the same benefits as the Pennzoil 5w-20. GC seems a bit on the thick side where as this M1 would be thinner and aid in gaining MPG.

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I've used Mobil 1 0w30 and 10w30 as well as GC. I didn't see any difference in mpg with any of those oils.

 

[Fred Bear]

I dont see a 20WT oil raising your MPG by 2 MPG. Your driving habits must have changed.

 

[G-MAN]

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Originally posted by Fred Bear: I dont see a 20WT oil raising your MPG by 2 MPG. Your driving habits must have changed.

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Wrong. They haven't. My driving habits, and even where I drive, are remarkably uniform.

 

[Darryl]

My round trip to work and back is 92 miles (46 one way). I live 1/2 mile from my freeway on ramp, and my work is less than that from the off ramp. I live in the high desert of So Cal and I never have any traffic to deal with, also I work "off" hours. So the freeway is 90 of the 92 miles, I set my cruise control to 67.5 mph (if you own a Dakota you know why it's 67.5). As I said, the weather has been great and very consistant. In the morning there is zero wind and in the afternoon there is a good breeze. I did not soft pedal the truck any more than I normally do, I was very consistant with my driving style as well as my route. So with all the info I gave you, I think it's clear to see that the 2.3 mpg increase is for real. I think 5w-20 today is like the 4 cylinder of the 70's. Could you imagine in 1974 someone telling you that Honda was going to get 240hp from a 2000cc, 4 cylinder motor?..... You would still be laughing. Thats technology for ya. Darryl

 

[427Z06]

Darryl, would it be safe to say that your driving style is "easy" on the engine since you mentioned that you soft pedal it, drive for 91 miles with cruise control on (67.5), and don't have to deal with any traffic, and your climate is relatively mild?

 

[Darryl]

Yea, that would be a fair statement, except for the mild climate. In the high desert of So Cal, it gets down to 20*f (not real cold) in the winter......BUT in the summer it gets to and stays well over 100*f from mid May to mid October. My truck is very quick, but I like to drive it like it's paid for and not stolen. Darryl

 

[427Z06]

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Originally posted by Darryl: In the high desert of So Cal, it gets down to 20*f (not real cold) in the winter......BUT in the summer it gets to and stays well over 100*f from mid May to mid October.

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Even though it does get hot there, with your nice steady 67.5 cruise, you probably get plenty of air flow and your oil never get overly hot. Sounds like you got a good thing going there.