30 weight oil talk.

Status
Not open for further replies.
Probably wouldn't work though I always smell like a car I guess she's used to it. Doesn't comolain about the stained up jeans and dirty nails any more either and It only took 3 years and she says she has me trained
smile.gif
 
Don't remember where I read it, but either someone on this forum or another had a part time job for some automotive parts place. They were going to "recycle" all their straight weight oils that didn't sell for $0.50 a quart or something.
He bought all 60+ quarts of 30 weight and used it without a hitch. Doing 2 oil changes a year he would use 1 quart of 5w20 during the winter months, or something like that.

Now that I think about it due to my Leaky Taurus (vulcan 3.0 V6 SOHC). I should probably start shopping around for some Straight 30. Right now I am running a long drain of Maxlife 10w30 topped off with Supertech 15w40.
Perhaps 30 weight would be more like 15w40 when "cold" and more like a true 30 weight when it gets warmed up.
 
When I first started changing oil on cars (mid 70s), it was thought that multigrades were not as durable, that they broke down more quickly than single grades. It was also thought that multi-grades caused sludge, because of the viscosity improvers in them...if you wanted to keep your engine clean and make it last, you chose a single grade appropriate to the season...
seems that school of thought has persisted.

Let me guess, this guy is over 50...
 
Last edited:
Originally Posted By: chevyboy14
And what would the advantages of using something like that vs say a regular conventional 10w30 oil


I can't remember exactly who explained it to me, but a 10w30 is a 10 weight oil built up with viscosity index improvers to make it into a full 30 weight as the oil gets hotter. Viscosity index improvers are long braided molecular chains that roll out and thicken up the oil when the oil gets hotter. Have you ever seen one of those rope ladders that they throw out the side of a helicopter when they go to rescue someone out of the ocean? VII's are long molecular chains that look like rope ladders. When the oil is cold, all the rope ladders are all rolled up and stowed away. But when the oil heats up and gets hotter, all those rope ladders start getting rolled out the side of the helicopter. At 200 degrees Fahrenheit, all your rope ladders are rolled out to make the oil a full 30 weight. A straight 30 weight oil, has no rope ladders to wear out.
 
Originally Posted By: Quattro Pete
Originally Posted By: JAG
He is probably old and probably also wears Old Spice cologne.

Or maybe he uses the straight 30 weight as deodorant, too.


I used to use a straight 30 but have recently switched to 5w30 on my dresser....just a 1L bottle, jug is a little unwieldly!
 
Originally Posted By: cp3
Originally Posted By: Quattro Pete
Originally Posted By: JAG
He is probably old and probably also wears Old Spice cologne.

Or maybe he uses the straight 30 weight as deodorant, too.


I used to use a straight 30 but have recently switched to 5w30 on my dresser....just a 1L bottle, jug is a little unwieldly!


I found that actually, a 0w30 is easier to put on on a cold morning. A straight 30 grade took forever...
whistle.gif
 
Originally Posted By: Quattro Pete
Originally Posted By: JAG
He is probably old and probably also wears Old Spice cologne.

Or maybe he uses the straight 30 weight as deodorant, too.


He likely uses MMO for both deodorant and aftershave
grin.gif
 
Originally Posted By: OVERK1LL
Originally Posted By: Quattro Pete
Originally Posted By: JAG
He is probably old and probably also wears Old Spice cologne.

Or maybe he uses the straight 30 weight as deodorant, too.


He likely uses MMO for both deodorant and aftershave
grin.gif



Or drinks Auto-Rx when he's having stomach troubles...
 
Originally Posted By: Merkava_4
Originally Posted By: chevyboy14
And what would the advantages of using something like that vs say a regular conventional 10w30 oil


I can't remember exactly who explained it to me, but a 10w30 is a 10 weight oil built up with viscosity index improvers to make it into a full 30 weight as the oil gets hotter. Viscosity index improvers are long braided molecular chains that roll out and thicken up the oil when the oil gets hotter. Have you ever seen one of those rope ladders that they throw out the side of a helicopter when they go to rescue someone out of the ocean? VII's are long molecular chains that look like rope ladders. When the oil is cold, all the rope ladders are all rolled up and stowed away. But when the oil heats up and gets hotter, all those rope ladders start getting rolled out the side of the helicopter. At 200 degrees Fahrenheit, all your rope ladders are rolled out to make the oil a full 30 weight. A straight 30 weight oil, has no rope ladders to wear out.


Then you had it explained to you incorrectly.

VII's are indeed polymers that expand and contract. But base oils have a natural VI that will dictate a degree of multi-grade performance without the use of ANY VII's whatsoever.

Take a look at what Pablo posted above:

AMSOIL's "straight 30" diesel oil is actually a 10w30, since the natural VI of the base oils allow it to behave as one. But since it has no VII's in it, it is also a "straight 30".

A MODERN multi-grade oil will use a blend of base stocks that get the oil as close to its desired performance as possible and then will use a dose of VII's to improve the VI to get the rest of the way.
 
Originally Posted By: Merkava_4
Originally Posted By: chevyboy14
And what would the advantages of using something like that vs say a regular conventional 10w30 oil


I can't remember exactly who explained it to me, but a 10w30 is a 10 weight oil built up with viscosity index improvers to make it into a full 30 weight as the oil gets hotter. Viscosity index improvers are long braided molecular chains that roll out and thicken up the oil when the oil gets hotter. Have you ever seen one of those rope ladders that they throw out the side of a helicopter when they go to rescue someone out of the ocean? VII's are long molecular chains that look like rope ladders. When the oil is cold, all the rope ladders are all rolled up and stowed away. But when the oil heats up and gets hotter, all those rope ladders start getting rolled out the side of the helicopter. At 200 degrees Fahrenheit, all your rope ladders are rolled out to make the oil a full 30 weight. A straight 30 weight oil, has no rope ladders to wear out.


The guy that uses 30W fell out of a helicopter?
 
Originally Posted By: chevyboy14
Is there an advantage I'm not aware of in using straight weight oil.


There would be no advantage in a water-cooled engine that is operated in a non-fleet environment.

For something like a taxi that never shuts down and idles for 12 hours a day, SAE30 "may" be suitable, but i still don't see any advantage.
 
I run a 68 Torino with a juiced up 302 fitted a bit loose--re:forged pistons. I use 30 wt. Pennzoil. Gasoline is great for a deodorant. Smell like a man. John--Las Vegas.
 
'Modern' straight-30's are actually closer to being around a 15w30, b/c modern base oils are that good.

In warm to moderately cold climates, straight-30 will work basically as well as any 10w30.
 
Quote:
I can't remember exactly who explained it to me, but a 10w30 is a 10 weight oil built up with viscosity index improvers to make it into a full 30 weight as the oil gets hotter.
Except it isn't. The base oil with its own viscosity index is the start, plus some index improvers to make the final hot spec and pour point depressants to meet the low spec. Can a straight 10 wt meet the 30 wt HTHS minimum spec of 2.9 mPa with any amount of VIIs AND meet the 10W cold cranking and cold pumping max specs at -25°C and -30°C respectively? Not likely.

The guy who uses straight 30 probably scoffs at the notion of an oil as thin as 10 wt when cold and actually thickens to 30 wt when hot---
crazy.gif
. His action shows how tolerant our engines are to oils.
 
Status
Not open for further replies.
Back
Top Bottom