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Synthetic, Blend, or Conventional Oil?

Jerry Bransford

TJ Guru
Supporting Member
Nov 9, 2015
10,958
Escondido California
I use the TG8A or equivalent. Its a bigger version of the TG16....more filtration.
The TG16 doesn't filter the oil any better than the TG8A does, they use the exact same filtration material. Both share the same 99% filtration efficiency rating. The larger model can go longer between changes since it has a larger filter surface area area to trap dirt in but that's really its only real advantage. Both filter down to the same exact size of particulates (dirt). The slightly larger oil capacity is insignificant.
 

Kiwi TJ

I don't suffer from insanity I enjoy every minute
Supporting Member
Ride of the Month Winner
May 3, 2016
4,222
Auckland New Zealand
I use semi - Castrol Magnatec...used it for years without any issues....but yes regular oil/filter changes
 
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superduty

TJ Enthusiast
Apr 7, 2016
259
So Cal
The TG16 doesn't filter the oil any better than the TG8A does, they use the exact same filtration material. Both share the same 99% filtration efficiency rating. The larger model can go longer between changes since it has a larger filter surface area area to trap dirt in but that's really its only real advantage. Both filter down to the same exact size of particulates (dirt). The slightly larger oil capacity is insignificant.

Good job Jerry...you caught me with a bad choice of words using "more filtration".

I guess the better choice of words would have been "more filtration area", which I can only assume is beneficial.





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pagrey

TJ Enthusiast
Apr 10, 2018
780
Los Angeles, CA, USA
Changing the oil and filter at appropriate intervals is the key to engine longevity, not synthetic or conventional.

That said I've run nothing but conventional engine oils since 1964 when got my first car and I've never had an engine problem. Then again I keep the oil and filter changed.
Agree.

Blackstone labs test oils and this is what they have to say:
https://www.blackstone-labs.com/wp-content/uploads/2018/09/Aug-17-ENG.pdf

Personally I have no useful data because I've only had 20 or 30 cars, these guys have tested thousands. I run cheap Chevron from Costco or Proline from Walmart because I have better things to spend my money on.
 
OP
rasband

rasband

LJR
Supporting Member
Sep 11, 2018
655
Denver, CO
Good job Jerry...you caught me with a bad choice of words using "more filtration".

I guess the better choice of words would have been "more filtration area", which I can only assume is beneficial.
I would love to see data on this, have you seen any sources on the concept? I tend to go manufacturer spec and keep tabs on it in my cars (so far so good, knock on wood). Just wanted to hear other TJers experiences!
 
Changing the oil and filter at appropriate intervals is the key to engine longevity, not synthetic or conventional.

That said I've run nothing but conventional engine oils since 1964 when got my first car and I've never had an engine problem. Then again I keep the oil and filter changed.
Then again, you are in a warmer climate, probably not dealing with block heaters, battery tenders, radiator shields, etc., etc.
Synthetic oil does have a few benefits for northern folks . . .
 
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rasband

rasband

LJR
Supporting Member
Sep 11, 2018
655
Denver, CO
Then again, you are in a warmer climate, probably not dealing with block heaters, battery tenders, radiator shields, etc., etc.
Synthetic oil does have a few benefits for northern folks . . .
So we know what some from the warmer climates prefer, where are the colder climates at? Last post I saw was the filter rec, what oil do you like? Earlier:

What's everyone using for oil filters . . . . ? (4.0L inline 6)
Wix 51085XP or 51085
 

steelhd

TJ Enthusiast
Jan 1, 2019
156
Eastern WA
Have you heard of Blackstone Labs? They have been testing oil since 1985 and here is what they have to say about that...
https://www.blackstone-labs.com/information/faqs/gas-diesel-questions/

"What’s the best oil to use?
Ah, the million dollar question. We are an independent lab, so we don’t make recommendations. It has been our experience that oil is oil, and either petroleum or synthetic-based oil will work well for just about any engine.

Come on, you’re holding out on me. I should use synthetic, right?
Buddy, you should use whatever you want. Synthetic oil won’t guarantee a longer engine life any more than my eating organic food will guarantee I’ll live until I’m 90. We here at Blackstone generally use regular petroleum-based oil because honestly, it works just as well for us."
 

JEEPCJTJ

TJ Enthusiast
Supporting Member
I use the TG8A or equivalent. Its a bigger version of the TG16....more filtration.
Not sure of the brand but the bigger one is what I used the first time I changed my TJ oil.

The TG16 doesn't filter the oil any better than the TG8A does, they use the exact same filtration material. Both share the same 99% filtration efficiency rating. The larger model can go longer between changes since it has a larger filter surface area area to trap dirt in but that's really its only real advantage. Both filter down to the same exact size of particulates (dirt). The slightly larger oil capacity is insignificant.
While all this makes perfect sense my reason behind the bigger filter was because it's what was always used back in the days of the 258 (and leaf springs;)). Now even though I used it the first time I'm going to try the "correct" filter the next time because the long one was a challenge to fit through all the crap that was in the way. Hopefully it will be easier.
 

Alex0413

TJ Enthusiast
Oct 26, 2018
135
Baton Rouge, LA
Synthetic oil is far superior to conventional oil, after all the money we put into our rigs, why are so many people opposed to spending the extra $8 for synthetic? The thermal breakdown properties are far superior, Base Number much higher resisting engine acids, and you have far better viscosity at cold start up protecting your engine. with the heavy rock crawling we do in summer heat, I want that extra protection.
 

Mr. Bills

TJ Addict
Nov 24, 2017
1,562
Area Code 530
Synthetic oil is far superior to conventional oil, after all the money we put into our rigs, why are so many people opposed to spending the extra $8 for synthetic. . . ?
For me it is not an issue of being "opposed" to spending more money for synthetic oil. Instead, it is simply that there is little benefit in relation to the additional cost because I don't try to extend oil change intervals beyond 5,000 miles and I don't live where the ambient temperatures are regularly below 30 degrees - the two situations where synthetic oil is documented to be "superior" to conventional oil.

The reason I use Valvoline Maxlife synthetic blend 10w30 rather than Valvoline conventional 10w30 is that I am not immune to the marketing pitch that Maxlife contains an additive package that benefits higher mileage engines. Other than that I have no reason to believe that one is any better at lubricating my engine than the other.

Today's prices at Walmart.com:

Valvoline conventional 10w30 - 5 qt. bottle, $17.97

Valvoline Maxlife synthetic blend 10w30 - 5 qt. bottle $17.97

Valvoline full synthetic 10w30 - 5 qt. bottle regularly $25.97, current rollback price $22.97.


I typically change the oil twice each year, at 5,000 miles or every six months. The cost difference between conventional oil/Maxlife and synthetic would be only $10-$16/year so my choice of oil is not cost driven, however it is tough to ignore the fact that $16 almost covers the cost of one of the two oil changes with conventional or Maxlife.
 
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Alex0413

TJ Enthusiast
Oct 26, 2018
135
Baton Rouge, LA
I'm in the distillation business, and I can assure you that synthetic being superior isn't a marketing pitch. It's a completely different refining process than conventional oils that remove all impurities. I'm not saying at all that conventional oil is bad or will cause problems for your engine, but synthetic is indeed better, and for the couple of extra bucks it cost, i'm always going to buy it.
 
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tworley

TJ Addict
Supporting Member
Ride of the Month Winner
May 23, 2018
2,269
Morrison, CO
I ran synthetic in my diesel when I had it, IIRC it was a 5w and ran a 0w in the winter. But thats a whole other animal right there. I drove that thing everywhere and a 10k mile interval was much better, synthetic made sense.
 

superduty

TJ Enthusiast
Apr 7, 2016
259
So Cal
I ran synthetic in my diesel when I had it, IIRC it was a 5w and ran a 0w in the winter. But thats a whole other animal right there. I drove that thing everywhere and a 10k mile interval was much better, synthetic made sense.
For the first time in 150k miles I'm gonna try synthetic in my Ford diesel. I have heard lots of good reviews in the diesel world.

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Jay MacLeay

TJ Enthusiast
Is there anything I should do if I have been using synthetic and want to switch to regular? I have been dealing with a slight rear main seal leak ever since I bought the Jeep. I even replaced the seal only to have it continue to leak. I'd like to see if switching to regular oil will stop the leak.
 
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Mr. Bills

TJ Addict
Nov 24, 2017
1,562
Area Code 530
Is there anything I should do if I have been using synthetic and want to switch to regular? I have been dealing with a slight rear main seal leak ever since I bought the Jeep. I even replaced the seal only to have it continue to leak. I'd like to see if switching to regular oil will stop the leak.
Nope. Just change your oil and filter and go.
 
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