Going by HTHS

Status
Not open for further replies.
Joined
Dec 15, 2017
Messages
3,275
Location
On another site
In many posts here, I have seen reference to choosing a motor oil based on HTHS rather than SAE or other ratings, and the discussions are appealing for numerous reasons.

M1 0w-40 has been touted as a great oil (and it is) with HTHS 3.6.

Wanted to get thoughts on using an oil with an HTHS rating a little higher, say between 4.0 and 4.1. I know there is a point of diminishing return but would like to hear what the BITOG experts have to say.
 
IMO, since they found out that regular "grades" didn't predict wear, and that HTHS DID, they should have dropped the KV100 grade, and adopted xW-HTHS.

IMO, much above 3.6 to 3.8 in most cases is wasteful of economy, without any benefit in terms of wear or high temperature protection.

It pushes you typically into areas like 15W40s with thick base oils, and less than stellar cold weather performance.

I'd use a 15W40 over 20W50 any day of the week...but wanting a synthetic pushes me into 5W40s, and 3.7 to 3.8
 
So where would a straight 30 sit, see all info on multigrades of course, but they gloss over the straight weights. Curious because I am using it in my BMW motorcycle this year, and BMW recommend it for a bit narrower range than the normal 20W-50 everyone uses. Up to 30c...and we've been going a tad over that lately, sump temps are good with a temp gun. They must be happy with it's HTHS, and the bike is running great.
 
Straight 30 is 3.4-3.6
Originally Posted by Silk
So where would a straight 30 sit, see all info on multigrades of course, but they gloss over the straight weights. Curious because I am using it in my BMW motorcycle this year, and BMW recommend it for a bit narrower range than the normal 20W-50 everyone uses. Up to 30c...and we've been going a tad over that lately, sump temps are good with a temp gun. They must be happy with it's HTHS, and the bike is running great.


Straight 30 is around 3.4-3.6.
Straight 20s were around 2.9.

What happened was that multigrades came in, and were widely adopted. But over time, they realised that the engines were not being protected as well as the "grade" predicted that it should have, given the grade.

So they started looking at what happened, when viscosity modifying polymers were exposed to high shear rates in engines, and found that the polymers stretched out, and lost (part of) their thickening abilities, behaving as a thinner oil in the bearings.

That's when HTHS was developed, and became a part of the J300 oil specs.
30 grades, which were typically HTHS 3.5 were given a 2.9 minimum (where a straight 20 grade would be). 20s were given 2.6. 40s were given 3.5 for 15W, 20W, and 25W 40s, while the 0W, 5W, and 10W 40s were given 2.9 minimum same as the 30s.

Below is a test that I think was really clever...a Pommie 4 cylinder that they tapped into number 4 main bearing, and supplied with a constant pressure oil feed, measuring it's flow rate to infer viscosity.

It shows how a mono is a Newtonian fluid, it's viscosity doesn't get affected by shear rate, and how multis have a Newtonian early stage, tehn change viscosity rapidly over RPM ranges, then establish the "second Newtonian" range where the stretched out polymers don't "shear" anymore..

Personally, I prefer to pick the second stage (HTHS), and not have it overly "thick" in the early stage...that's whiy I'm not a fan of polymeric VIIs...espcaially in temperate climates.

Bearing Viscosity.JPG
 
Thanks for the post on the relationship between viscosity and engine performance. It's hard to get good data.

I believe the charts above were from The Book "The Relationship between Engine Oil Viscosity and Engine Oil Performance", by Lonstrup, Bennett, Waddy. STP621.

In Fig. #5, they presented the relationship in apparent viscosity of polymer thickened multi grade oil against engine rpm. I am assuming the oil sample was a typical mult-grade oil available at or before the time of publishing the book. The book was published in 1977 so the data represented was for an oil manufactured 42 years ago.

Times have changed and although conceptually correct that chart would now show very little difference across the range of RPM, due to the much improved oil technology in the last 42 years.

Again the concept is correct but its application is almost obsolete. It's also why 0w40 oils are widely available from many of the major manufacturers. These new multiviscosty oils are not the same as Grampa's.

Of course add gasoline contamination from GDI, and you will see degradation.
 
Last edited:
Take the engine maker's recommendation for HTHS in the Owner's Manual. If you tow or race, especially in the summer, then add 0.2 to 0.5 HTHS to that recommendation. Otherwise, just go with whatever they say in the Owner's Manual.

They don't say explicitly what HTHS they want, unfortunately. You have to look at the oil specification and/or oil examples for the allowable range and look it up on the internet.
Example: a new GM V8 pickup truck says use dexos1 0w20, OK, fine, that's a typical HTHS of 2.7, so add 0.3 or so to it and you'll find yourself using something like M1 AFE 0w30 for towing (...I doubt you're racing it, but, hey, rednecks will be rednecks...).

.... Also, add around 0.3 HTHS if you suspect fuel dilution to any extent, as with Honda turbo engines & ecoboosts, etc., usually in those types of engines.

So it depends on the engine. Vehicle manufacturers do durability testing so it's fine to use what they say, just realize you can and probably should go a little higher on HTHS if towing-racing-fuel-diluting.

See the 6:35 point in the video https://www.youtube.com/watch?v=0B6SHa4qv60 for some field testing GM did a few years ago. Different engines may react differently to various HTHS lower limits.
 
They do call out the minimum required HTHS that the engine requires by recommending or explicitly calling for an API licensed or certain ACEA requirement for engine oil in the appropriate viscosity. They know by calling for a 5w20 API licensed fluid it's going to have a minimum HTHS value. They just don't put the HTHS directly because your typical owner is already confused enough and HTHS isn't printed on oil bottles.

I'm of the camp that oil additives have come a long way and will provide the adequate sacrificial layer for wear protection when the proper oil weight called for by the OE is used under the conditions the OE has said it is good for.
I.e. 20wt for normal driving conditions, 30wt for towing / performance applications and 40-50wt's in extreme performance applications as an example.

To stress about HTHS with modern oil additives we have today is not necessary or the OE's would "require" it. No need to use a 0w40 in a Xw20 rated application.
We don't see Joe Consumer stressing about HTHS and their vehicles see long lives on bulk "whatever" oil usually run longer than it should be and most of the time conventional which we know isn't as great as synthetic oil's properties.

Use what your OE says to use and use a quality oil it's that simple. There is lots of high mileage folks here running on 20wt's at high miles to boot as we have had these oils for over a decade.

And before anyone points to me using a 0w30 in my Caravan that calls for a 5w20, I'm doing so because I wanted to see how it compares to my father in-law's van UOA running 5w20 and what my UOA shows in comparison. I also wanted to try it out because the van used to spec 5w30 as standard and it seems quieter on this oil. It's experimentation only, not because I don't think a 20wt will protect it well enough. Just wanted to be clear on that.
 
Last edited:
Originally Posted by dblshock
throw in fuel dilution and turbo heat .... your polyannish opinion melts.

So Honda 1.5T's are imploding with the massive fuel dilutions and calling for 20wt oil and a HTHS of 2.6 typically? They are diluting so much that it raises oil level and they have Turbo's with lots of heat. Where is the failures?
I'm not saying it's good for the engines but that alone proves that it isn't a panic situation "I better switch to 0w40". So surely those having dilution at 2% or less have absolutely nothing to worry about.
 
Last edited:
Originally Posted by StevieC
Originally Posted by dblshock
throw in fuel dilution and turbo heat .... your polyannish opinion melts.

So Honda 1.5T's are imploding with the massive fuel dilutions and calling for 20wt oil and a HTHS of 2.6 typically? They are diluting so much that it raises oil level and they have Turbo's with lots of heat. Where is the failures?
I'm not saying it's good for the engines but that alone proves that it isn't a panic situation "I better switch to 0w40". So surely those having dilution at 2% or less have absolutely nothing to worry about.


Even the Type R's spec 0W20
 
Originally Posted by Jimmy_Russells
Even the Type R's spec 0W20
I'd be using M1 AFE 0w30 in those Honda turbo engines. They do seem to have decent tolerance to HTHS dropping down to 2.0 (or maybe below) though. Wonder how many spun bearings or scored cylinders are happening? Honda won't tell us. ... Maybe some excess wear in the fuel-diluting ones we can't see or note, so safer to bump up HTHS a tad here.
Honda hasn't bumped up the viscosity recommendations. They should.
 
As long as the heat is controlled and fuel dilution is kept to a minimum there should be no issue with a 20wt in a Turbo application. Honda isn't the only one doing this.
My aunts Juke which puked the CVT called for a 20wt in a turbo application and she changed the oil about every 8,000 miles (not kilometers)
 
They only care for it to make it thru the warranty period. After that its on your dime. How else do you sell new vehicles. 90% of people trade before a vehicle gets to 100,000 miles so that dime is on the next owner and they don't [censored] about it when it dies. Very few of us run them to 500k and that's why we don't run thin syn oil
 
Originally Posted by rideahorse
They only care for it to make it thru the warranty period. After that its on your dime. How else do you sell new vehicles. 90% of people trade before a vehicle gets to 100,000 miles so that dime is on the next owner and they don't [censored] about it when it dies. Very few of us run them to 500k and that's why we don't run thin syn oil

Over a decade of 20wt oils and we don't see cars failing just past the warranty on Jiffy Boob 20wt's. Lots of high mileage engines out there and we have the UOA's here to prove it.
21.gif


Where are the consumer advocacy articles saying you might want to think again about 20wt oils? They certainly have enough of the "Use synthetic instead of conventional" articles and the "Change it every 3K miles or not" articles.

Fear is overblown for no good reason or the HONDA 1.5T's with massive amounts of fuel and turbos would be done like dinner and not surviving those harsh conditions.
That alone should prove it. It's literally the worst case scenario. Where is Honda advising 0w40 and higher HTHS to stave off failures?

Honestly this forum needs to take a Xanax
 
Last edited:
Originally Posted by StevieC
Originally Posted by rideahorse
They only care for it to make it thru the warranty period. After that its on your dime. How else do you sell new vehicles. 90% of people trade before a vehicle gets to 100,000 miles so that dime is on the next owner and they don't [censored] about it when it dies. Very few of us run them to 500k and that's why we don't run thin syn oil

Over a decade of 20wt oils and we don't see cars failing just past the warranty on Jiffy Boob 20wt's. Lots of high mileage engines out there and we have the UOA's here to prove it.
21.gif


Where are the consumer advocacy articles saying you might want to think again about 20wt oils? They certainly have enough of the "Use synthetic instead of conventional" articles and the "Change it every 3K miles or not" articles.

Heck where is "Consumer Reports" on this issue?


Honda can build engines, they have proven that (and not only in cars) for decades now. If it were my car I would use the highest HTHS 20 weight API certified oil I could find, and drive the crap out of it.
smile.gif
 
Originally Posted by StevieC

So Honda 1.5T's are imploding with the massive fuel dilutions and calling for 20wt oil and a HTHS of 2.6 typically?


There have been some engine failures and a very large number of engines going into limp mode or simply shutting off. There is some speculation that a mild engine seizure is causing the sudden stop. It's good to remember that the oil dilution issue on the Honda 1.5 happens in more frequently in cold weather, when oil is more viscous, possibly mitigating wear.

Honda's carefully worded statement claims that their lab tests of these engines "show no significant damage" . What about the real world?

There is a class action suit out of Georgia (a warm southern state) indicating failures.

Furthermore, the software "fix" is annoying owners, as the idle speed has been increased, MPG decreased and the fuel dilution continues.
 
Yes but with 20% fuel dilution I don't think any engine is meant to operate like that it's not a fault of the 20wt oil.
When it's raising the dipstick level that is contributing to the problem both from the fuel dilution and I'm sure is happening from the oil being over filled.

It's not all of them just the severely diluted / overfilled ones...
 
Last edited:
I entered a contest at the Toronto Auto Show to win a 2019 Honda Civic Sedan (touring edition) and it has the 1.5 turbo in it so I guess if I win I get to be a test bed to see if I can make the engine survive
laugh.gif
 
Originally Posted by Patman
I entered a contest at the Toronto Auto Show to win a 2019 Honda Civic Sedan (touring edition) and it has the 1.5 turbo in it so I guess if I win I get to be a test bed to see if I can make the engine survive
laugh.gif


They are fine with shorter OCI's to keep fuel dilution to a minimum. Good Luck!
grin2.gif
 
Last edited:
Originally Posted by StevieC
Fear is overblown for no good reason or the HONDA 1.5T's with massive amounts of fuel and turbos would be done like dinner and not surviving those harsh conditions.
That alone should prove it. It's literally the worst case scenario. Where is Honda advising 0w40 and higher HTHS to stave off failures?

Honestly this forum needs to take a Xanax


The Honda engine is not a great example, as it has been problematic.

https://topclassactions.com/lawsuit...ys-civic-cr-v-vehicles-defective-engine/
Quote
Pointing to the fact that Honda recalled these vehicles in China in March 2018, Hamilton argues that the company knew of the defect and intentionally decided to not tell American consumers about it.


Minnesota CAL:
https://www.carcomplaints.com/news/2018/honda-earth-dreams-engine-lawsuit-cr-v-civic.shtml

Georgia CAL:
https://www.carcomplaints.com/news/2018/honda-fuel-dilution-problems-class-action-lawsuit.shtml

Consumer Reports coverage, including noting that the engines have been stalling:
https://www.consumerreports.org/car...-turbo-engine-fix-details-rollout-plans/

The solution being presented for the US and Canada is:
Quote
Honda Canada says 2017-2018 CR-Vs and 2016-2018 Civics will be subject to repairs designed to address the problems of high oil levels and oil dilution after owners of models with the new 1.5-L turbocharged gas engine started noticing high oil levels on the dipstick caused by fuel mixing with the motor oil.

Affected owners will receive new uploaded software, and dealers will also change the engine oil and in some cases the air conditioning control units. The modifications will apparently allow the engines to warm up faster and improve fuel combustion in cold weather to prevent unburned gas from diluting the engine oil.

The repairs are being made to Canadian models first and before those of U.S. owners living in northern states. The problem was first documented by Honda buyers in China, who had complained of illuminated engine/oil warning lights and damaged engines caused by fuel contaminating the oil, a problem Honda blamed on short drives made in extremely cold weather.

Canadian CR-V and Civic owners will have the benefit of warranty extensions on selected engine components for up to six years from the original date of purchase with no mileage limit.


However China has not deemed this sufficient.

Quote
A Stop-Sale Ordered in China
In February 2018, Dongfeng Honda - a Chinese car company half-owned by Honda - ordered a recall of 350,000 vehicles after numerous complaints from owners in the colder regions of northern China.

Honda planned on updating the vehicle's gasoline injection control software to adjust the timing and speed of the injection. They also planned on extending the engine's warranty to 6 years.

But the emphasis is on plan, because the recall was rejected by Chinese regulators, who want a better plan for fixing the problem.

Until a new recall is agreed upon, Honda has issued a stop-sale on all new CR-Vs in China.


https://www.carcomplaints.com/news/2018/honda-cr-v-civic-high-oil-levels.shtml
 
Status
Not open for further replies.
Back
Top