Oil ZDDP Rotella gas truck

tyler

Active member
Jun 22, 2013
513
90
28
My questions are
1. does synthetic take away the need for ZDDP
2. does this oil have the ZDDP independent of answer to #1

Rotella diesel engine oil has been recommended for a number of years because of the ZDDP being higher than others. I mostly used T4, than found some
synthetic T6 on sale - the T6 did quiet the motor the last year before disassembly which found bad bearings (from poor quality PO rebuild, not oil).

Here is a Rotella 5w-30 full synthetic gas truck oil - on sale 5 quarts for $15.

https://www.homedepot.com/p/160-oz-ROTELLA-for-GAS-TRUCK-5W30-550050319/309170386?irgwc=1&cm_mmc=afl-ir-1378631-483420-&clickid=ROlVG9SJdxyORV0wUx0Mo38qUkE1QTzBrUQdzg0

I could not find the numbers, if I did, I would still not know what is needed.

TIA

--
1975 Glenbrook, 1978 Royale rear bath
Raleigh, NC
 
Some of the synthetics have high levels of ZDDP, but most modern oils do not. Google the brand and ZDDP and you should find a lot of info.

In my opinion, ZDDP is necessary. I had a 1968 Cadillac I drove as a daily driver — 75k miles in about 2 years. The cam and lifters became EXTREMELY worn/rounded, and that’s pretty uncommon with those motors. Was lack of ZDDP the cause? In my opinion, yes.

Does it hurt to run our GMC motors with ZDDP oil? No. Does it hurt to run out motors with no-ZDDP oil? Likely, but opinions vary. I’ll take the ZDDP.

-Dave
1978 Transmode near Pittsburgh

>
> My questions are
> 1. does synthetic take away the need for ZDDP
> 2. does this oil have the ZDDP independent of answer to #1
>
>
> Rotella diesel engine oil has been recommended for a number of years because of the ZDDP being higher than others. I mostly used T4, than found some
> synthetic T6 on sale - the T6 did quiet the motor the last year before disassembly which found bad bearings (from poor quality PO rebuild, not oil).
>
> Here is a Rotella 5w-30 full synthetic gas truck oil - on sale 5 quarts for $15.
>
> https://www.homedepot.com/p/160-oz-ROTELLA-for-GAS-TRUCK-5W30-550050319/309170386?irgwc=1&cm_mmc=afl-ir-1378631-483420-&clickid=ROlVG9SJdxyORV0wUx0Mo38qUkE1QTzBrUQdzg0
>
> I could not find the numbers, if I did, I would still not know what is needed.
>
> TIA
>
> --
> 1975 Glenbrook, 1978 Royale rear bath
> Raleigh, NC
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Deciding on which oil to use in our engines is a tough one. I think Matt said it best when he said that it is hard to find a bad oil out there.
However I’m a believer in science and engineering, and if you are going to select an oil for our engines you might as well select one that has been
tested and compared to as many of the oils out there as is possible. Here is a link to a person that has tested over 240 different oils against an
engineered scientific set of parameters.

This is the article. It is updated monthly.

https://540ratblog.wordpress.com/2013/06/20/motor-oil-wear-test-ranking/

It is a tough read with lots of repetition and self service by the author, but is all that is out there that is not linked to the major oil brands.
Call it up, and grab the button on the right side of the page. Scroll down about 1/10 of the way to the “WEAR PROTECTION RANKING LIST”. It lists
oils that were tested by its ability to resist wear.

I personally use #8, 0W40 Mobil 1. The “0” for quick oil to the bearing surfaces in cold weather (I live in Wisconsin) and the “40” to give me
acceptable (to me) oil pressure during hot running. Also because it is listed high on the Wear Protection Ranking List.

Following is copy/paste from that article.

8. 0W40 Mobil 1 “FS” European Car Formula, ACEA A3/B3, A3/B4, API SN, synthetic = 127,221 psi
This new oil replaces the older version called, 0W40 Mobil 1, European Formula, API SN, synthetic. See below for the older version’s ranking
position.
zinc = TBD
phos = TBD
moly = TBD
This new “FS” version was tested in Summer 2016.
However, a 40wt hot viscosity rated motor oil is too thick to be ideal for most engines. It is best to select the thinnest motor oil viscosity that
will still provide acceptable “hot” oil pressure. And you do NOT need to select the “highest rated” motor oil, just as it comes right out of
the bottle, from this Wear Protection Ranking List. There are many highly ranked oils here, that will provide your engine with excellent wear
protection. So, you have many oils to choose from.
I also went on to test this oil at the much higher temperature of 275*F. At that elevated temperature, any hotter and thinner oil is expected to
experience a drop in Wear Protection Capability. This oil did have a 16% drop in capability. But, even at that elevated temperature, it produced an
impressive 106,876 psi, which put this much hotter and thinner oil in the INCREDIBLE Wear Protection Category.
I also tested this oil to find out its onset of thermal breakdown, which was 280F.

But I think that #5 would be a great oil to use. As the below says, this oil is available at Walmart reasonably priced. I’m using it in my cars.

5. 5W30 Quaker State Ultimate Durability, dexos 1 – Gen 2, API SN “Plus”, synthetic (green bottle) = 133,125 psi
This oil was tested again in late 2019 for two reasons:
1. It became available with the API SN “Plus” certification, so there was an interest in seeing if there were any changes in its performance.
2. This oil was purchased at Walmart. And that was significant because it was so shockingly cheap at Walmart, compared to mainstream Auto Parts
Stores, that there were concerns that Walmart might be selling counterfeit oil. Here’s why:
This oil was purchased at Walmart in late 2019, where the price was about $6.00 per quart bottle, and about $20.00 per 5 quart jug. At the same time,
a few miles away, this oil’s price at Pep Boys Auto Parts Store was about $9.00 per quart, and about $35.00 per 5 quart jug. So, there was a need to
find out if this oil being sold so cheap at Walmart was legitimate or not. Sure, you could say that Walmart makes such large purchases that it gets a
break on price. But then, you could say the same thing about Pep Boys Auto Parts chain stores. But, the proof was in the pudding as they say. And as
you can see by the psi value and ranking position above, this is the best performing 5W30 Quaker State Ultimate Durability, that I’ve ever tested.
So, Walmart gets a clean bill of health. They are selling legitimate QSUD, and there is nothing to be concerned about. Now, we would have a hard time
justifying buying this oil anywhere besides Walmart.
zinc = TBD
phos = TBD
moly = TBD
The psi value of this oil, which came from testing it at the normal operating test temperature of 230*F, put it in the FANTASTIC Wear Protection
Category.
However, I went on to also test this oil at the much higher temperature of 275*F. At that elevated temperature, any hotter and thinner oil is expected
to experience a drop in Wear Protection Capability. And this oil did have a 13% drop in capability. However, even at that reduced value down to
115,764 psi, this much hotter and thinner oil was in the INCREDIBLE Wear Protection Category.
I also tested this oil to find out its onset of thermal breakdown, which was 275*F.

If you want to see where the oil you use ranks, do a command F on an Apple or a ( I THINK) a control F on a PC and fill in the search
parameter, like “Mobil” or “Rotella”. That will highlight all of the occurrences of your oil in the document. Then do a carriage return down
until you find it.

If it is 5w30 that you need to use, at $20/5qt, why not use the highest one on the list.

Anyway, hope this helps.

Just my relatively informed, off the cuff, back yard mechanic, gut level, eyeball it up and guestimate, opinion….with a little engineering/science
to back it up…that’s all...

--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Rotella Gas Truck full synthetic is API SN Plus and Dexos GEN 2. Therefore it has those specs including ZDDP levels that must not be exceeded in SN
Plus. On the red jug it states it “ Meets or exceeds the requirements of ILSAC GF-5, API SN PLUS, API SN AND ALL PREVIOUS CATEGORIES” Remember
that ZDDP levels peaked with API SF in the mid 80’s and have been declining since. However if you believe the “AND ALL PREVIOUS CATEGORIES” that
should answer the question. It does not say “NOT FOR USE WITH NON ROLLER LIFTER CAMS”. Though ZDDP has been lowered in today’s gas and Diesel
oils, EP performance has been maintained through newer chemistry. What you don’t want to do is just add stuff to the oil you buy as in most cases
this works antagonistically to the new chemistry and degrades the oil’s performance. I have been running T6 5W-40 exclusively in my 455 and Onan.
The jug used to show semi’s, pickups and cars. Before coming out with the Gas Truck red jug line, they removed the gas vehicles from the T6 jug. I
just put 5W-30 Gas Truck oil in my 97 Tahoe replacing the T6. I will probably switch the GMC and Onan to it as well next oil change. Shell rebates
are fantastic as well.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
Tyler,

The whole and entire problem with ZDDP is that Zinc can foul a catalyst and an O2 sensor by a lessor amount. If you don't have these or if
replacement is not real expensive, use all the ZDDP you can get.

That is why I run M1 15W50 dopes with MoS2 and why I didn't need to do more than a light hone at about 80K on the rebuilt engine.

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
The big worry with lack of ZDDP in oil is the cam n lifters on flat tappet
engines. On Olds engines that also shows up on rocker arms where they meet
the valve stems ends. ESPECIALLY WHEN DOING BREAK INS ON REBUILT ENGINES
WITH AFTERMARKET camshafts and lifters. Many cam manufacturers provide
special break in oils when their cams are used in rebuilds. S & J engines
provide 6 quarts of special break in oils with their engines. Very strict
on break in instructions as well.
Jim Hupy
Salem, Oregon

On Sun, Dec 6, 2020, 5:10 PM Matt Colie via Gmclist
wrote:

> Tyler,
>
> The whole and entire problem with ZDDP is that Zinc can foul a catalyst
> and an O2 sensor by a lessor amount. If you don't have these or if
> replacement is not real expensive, use all the ZDDP you can get.
>
> That is why I run M1 15W50 dopes with MoS2 and why I didn't need to do
> more than a light hone at about 80K on the rebuilt engine.
>
> Matt
> --
> Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL,
> GMCES
> Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum
> Brakes with Applied Control Arms
> SE Michigan - Near DTW - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Mobil 1 had a fair amount of zddp in it last time I bought it more then enough for a 455
--
Roy Keen
Minden,NV
76 X Glenbrook
 
My coach, as far as I can tell, the previous own only used Rotella dino 15 W 40 It now has 135 K miles on it. and the oil consumption has fallen form
6000 per quart to 5000 per quart. Since I already used Rotella in my diesel John Deer and all of my air cooled engines (motorcycles, Onan, etc.) I
have stayed with it.

I do not use Dino Rotella in my newer vehicles. They want 0-20 weight oil not 15W40. I have had good results on everything using Rotella Dino oil so
I intend to stay with it. The only engine I have ever had with internal wear problems on was one using Mobil One since new. I am not a fan of
synthetics because of this.

In my opinion annual oil changes usually before parking for the winter to get rid of contaminants will buy you more than installing synthetic oil. My
local engine rebuilder uses Rotella 15W 40 oil and GM EOS, which is heavy ZDDP, in all flat tappet engines on break in. He also gives you an
additional 8 quarts (and Wix filter) for oil make up and to use on your first oil change at 3000 miles. After than he recommends 6000 miles or annual
oil changes with Rotella Dino oil.

There other high ZDDP oils out out there but I have no experience with them.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
> Mobil 1 had a fair amount of zddp in it last time I bought it more then enough for a 455

Roy,

I would have to look again, but last time I checked Mobil 1 - 15W50 was the only of their line with the high Zinc.

I do like synthetics because they resit forming acids better than most conventional lube oils.

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
You are correct Matt Meant to add 15 /50 to that statement all the rest as far as I know don’t have very much
--
Roy Keen
Minden,NV
76 X Glenbrook
 
Remember that ZDDP works against the detergent package. Adding it reduces the detergency. Adding ZDDP to excess will ruin your cam due to the P or
phosphoric acid in the compound spalling the finish. Adding ZDDP will increase general engine friction, while reducing friction only at the EP wear
points.
Also remember that Mobile 1 and Rotella are product family names and only that. Each product family has up to like 20 different products last I
looked. Some are good choices for a GMC and some are not. Saying you run Mobile 1 tells us nothing aa each product has a different spec sheet.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
Any good clean oil, changed frequently enough to rid your engine of
combustion by-products is good. On a well broken in engine. New rebuilds?
Jury is out.
Jim Hupy
Salem, Oregon

On Mon, Dec 7, 2020, 9:15 AM John R. Lebetski via Gmclist <

> Remember that ZDDP works against the detergent package. Adding it reduces
> the detergency. Adding ZDDP to excess will ruin your cam due to the P or
> phosphoric acid in the compound spalling the finish. Adding ZDDP will
> increase general engine friction, while reducing friction only at the EP
> wear
> points.
> Also remember that Mobile 1 and Rotella are product family names and only
> that. Each product family has up to like 20 different products last I
> looked. Some are good choices for a GMC and some are not. Saying you run
> Mobile 1 tells us nothing aa each product has a different spec sheet.
> --
> John Lebetski
> Woodstock, IL
> 77 Eleganza II
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>