Swithing from synthetic to Rotella 15w-40

[jaydeep]

I bought 92 vert with 59k. Previous owner took car to local shop for oil change. From what I can see from paper work they have used synthetic oil but probably 5w-30.
I do not want to change with syntatic since I will be putting only 2000 miles ever summer. Is it a good idea to switch?

[devon.818]

uhm 5w30 is fine for the e30, synthetic doesn't really do anything to these old ass cars man. the motors weren't designed for a 6k oil change, 3-5k on conventional.

now rotellaT is good shit, its cheap and works. use the lower weight, the thicker shiz not so good for a not so desiel if you know what im saying bud.


but really, a full syn. oil in a m20 just screams waste to me.

[Vivek]

That's all way too thin for an m20. They need 20w50. I don't really know why you'd put anything thinner in it unless it was super cold. I would absolutely not switch simply because you have a 59k m20 that's seemingly had synthetic for the past 20 years. It definitely doesn't need it, but it's not gonna hurt.

[Emre]

uhm 5w30 is fine for the e30, synthetic doesn't really do anything to these old ass cars man.

Shell Rotella isn't really a synthetic anyway: it's a Group III base stock.

now rotellaT is good shit, its cheap and works.

It's not as good as it used to be (less ZDDP than it used t have), but it's still great for the price.

use the lower weight, the thicker shiz not so good for a not so desiel if you know what im saying bud.

That makes no sense, really.

[Dsun]

so 15w-40 is no good? Im using chevron delo 15w-40

[Cletonius]

I run rotella 15w40 and change at 4k. Cheap and gets it done.

[WhyNot]

Shell Rotella ...It's not as good as it used to be (less ZDDP than it used t have), but it's still great for the price.

i am assuming the diesel motor oils have increased zddp...??
what oil has the highest zddp..?
can you caught zddp from a casual encounter..?
thanks

http://www.zddplus.com/

Why Can't We Use Diesel CI/CJ-4 Rated Oils?



There are some diesel engine rated oils on the market which may still have some ZDDP in them. There are problems associated with using these oils in a normal gasoline engine which can become severe in a high-performance gasoline engine. One issue is the high amount of detergent additive, and another is the high viscosity.

High detergent oil has a lower surface tension and lower shear pressure rating which can cause higher bearing wear in gas engines. A diesel engine needs oil with very high detergent capabilities in order to hold the large amount of combustion byproducts in suspension, but it is not optimized for a gasoline engine. The bearing journal size-to-displacement ratio on a gasoline engine is designed around the use of a lower detergent oil and relies on a high-shear rating to the oil.

The other problem with high detergent oil is that it actually reduces the friction reduction that the ZDDP affords, especially in a high-performance, high valve spring pressure engine.

The viscosity rating of most diesel rated oils is higher than optimum for our higher revving gasoline engines, and can cause oil starvation in bearings at high rpms.


As part of an effort to reduce vehicle emissions, the U.S. EPA offers vehicle manufacturers "credits" for early implementation as well as penalties for violation of emission reduction standards. The EPA's program called for 100,000-mile catalytic converter life by 2004, 120,000 miles by 2007, and 150,000 miles by 2009. To achieve these goals, automotive manufacturers have pressured their oil suppliers to remove substances from motor oils that would shorten the service life, including the proven EP (extreme pressure) additive ZDDP (zinc dialkyldithiophosphate). Zinc and phosphorus from the ZDDP can be present in small amounts in the exhaust gas of an engine depending on the amount of oil which is consumed in combustion. These elements can coat the catalyst reducing the amount of catalyst exposed to the exhaust gases, ultimately increasing emissions at the tailpipe. As a result of the EPA mandate, the ZDDP level in engine oils has been declining since the mid-1990s, roughly coinciding with the implementation of OBDII.

ZDDP has been an important additive to engine oils for over 70 years, and has an excellent track record at protecting the sliding metal-to-metal cam lifter interface. Historically, ZDDP has been added to oils in amounts resulting in approximately 0.15% phosphorus, and 0.18% zinc. ZDDP protects by creating a film on cams and flat lifter contact points in response to the extreme pressure and heat at the contact point. The film of zinc and phosphorus compounds provides a sacrificial wear surface protecting the base metal of the cam and lifter from wear. In the course of normal service, this conversion of ZDDP to zinc and phosphorus compounds depletes the ZDDP level in the oil. Studies show that depending on the specific engine and severity of duty, after 2000-4000 miles of operation, the level of ZDDP can drop below that considered adequate to provide wear protection to the cam and lifters.

According to the SAE Tech Bulletin # 770087 [1] , operation of a flat tappet engine without adequate EP additives such as ZDDP quickly leads to lifter foot scuffing and cam lobe wear. Camshafts are typically only surface hardened leaving the core ductile for strength. According to the SAE Bulletin, once cam lobe wear reaches 0.0002, "subsequent wear is usually rapid and catastrophic." Two ten-thousandths of an inch is one fifth the thickness of an average human hair.

In order to make engines last in the absence of ZDDP, virtually all IC (internal combustion) engines designed in the last ten years utilize roller lifters. Today, ZDDP has been removed from practically all automotive engine oils, rendering them unsuitable for use with older engines with non-roller lifters.


Question:
ZDDP Levels of Mobil Delvac
What are the current ZDDP levels for Mobil Delvac 15W-40? Is it recommended for classic engines with flat tappet camshafts? Answer:
Mobil Delvac 1300 Super 15W-40, which meets API CJ-4 performance standards, has a Phosphorus limit of 0.12 wt%. With respect to your question on slider tappets, Mobil Delvac 1300 Super 15W-40 meets Cummins CES 20081. This indicates the oil is suitable for use in their midrange engines (with Ultra Low Sulfur Diesel used in the US) which include the ISB and ISC series engines.

[stamar]

For the m20 20 50

for the m42 10 30

If it were mine I would stick with full synthetic

For just zddp check out a new product called quaker state defy. I dont know if its introdctary but at walmart defy which is semi syn, high mileage, high zddp is cheaper than regular rotella anyway.

I just looked at a zddp content list and regular castrol gtx has more zddp than rotella.

Shell rotella did a major marketing coupe thats still paying off, because the parent company took the zddp out of their regular oil ( penzoil)


the brand with the most zinc is VR. synthetic with the most zinc in valvoline also


i run rotella in my toyota truck actually. for the bmw 15 50 full synthetic.

[stamar]

one thing ill say about diesel oil is its very detergent and the first time you run it your oil gets filthy fast.

My truck had filthy oil in like 2000 highway miles like it hadnt been changed in years. drained it put in defy and its clean.

I think thats good but im watching for leaks.

[Dsun]

so in english, using Chevron delo 15w-40 is ok?

[dnguyen1963]

so in english, using Chevron delo 15w-40 is ok?

No, I would stay with Rotella 15W40. High detergent from Chevron might clean the engine too well that could lead to leaking down the road.

[SmokeE30]

i used to use rotella 15-40 all the time, for the money it really is good oil, but as stated bmw calls for 20w50 in the m20 and we all know we need high zinc content because of our valvetrains so i go with valvoline VR1 racing oil, its actualy pretty damn cheap and is great stuff, sure you could spend more for brad penn oil and shit but for off the shelf at autozone ect... VR1 20w50 is my vote

[stamar]

If your vert has the m42 bmw recomends full synthetic oil 10-30

theres no way to tell from your post although a 92 318ic is rare

for the m20 I still recomend full synthetic 15 50 mobil 1just changing at 6k miles. make it a lifetime vehicle. dont even let thinner diesel dino oil touch that thing.

oil nerds would love to have a zero wear engine like that Id sell it if I were you.

[Jaxx_]

That's all way too thin for an m20. They need 20w50. I don't really know why you'd put anything thinner in it unless it was super cold. I would absolutely not switch simply because you have a 59k m20 that's seemingly had synthetic for the past 20 years. It definitely doesn't need it, but it's not gonna hurt.

for real. If you use 5w-30 or 10w-30 you will hear a lot of noise from your valve train. Use the proper oil and don't listen to dumbasses that say that 5w-30 is okay for an M20.

[stamar]

thats why I think he has a 318 ic