Go Back   iRV2 Forums > MOTORHOME FORUMS > Class A Motorhome Discussions
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 07-17-2012, 01:33 PM   #43
Senior Member
 
Join Date: Aug 2000
Location: Walnut Creek Ca USA
Posts: 641
Synthetic oil was originally formulated for use in aircraft that had higher operating temperatures and an oil was needed that would not coke like conventional oil does at high temperature. Somehow that got translated to engines run cooler that use synthetic. So, does that mean some environments run cooler when using synthetic. The answer is maybe.

Heat is generated in direct proportion to friction. So, the real question is does use of synthetic reduce friction. Some tests reveal that synthetic base stock does resist shear at high pressures but most engines don't produce great shear values. Gear boxes produce high shear values and in testing running temperatures of gear boxes were reduced slightly by the use of synthetic base stock. Synthetic oil also has the ability to hold particulates in suspension better then conventional oil. Does that mean you can run longer change intervals? The answer is maybe.

Engines, and especially diesel engines have very high compression ratios. Compression also forces particulates past engine rings and into the oil where these contaminates are held until a specified drain interval removes them. While the base particulate loading in synthetic performs better then conventional oil, the engine continues to force particulates past the rings loading heavily the motor oil with carbon. Carbon is harder then steel.

Synthetic oils are only slightly more lubriscious then conventional oil, especially at high temperatures, and their long chain molecules are somewhat more resistant to shear, in heavily loaded environments like engines, they perform only slightly better then conventional oil and run no cooler.

The bottom line here is it worth the additional cost? In most diesel engines that need 12 quarts of oil to fill the crank case or more the answer is no unless you put on an average of 250,000 miles a year on the engine. Most owners of RVs do not even approach this kind of use. Over the road, long haul truckers that put 350,000-500,000 miles a year on their rigs, perhaps can justify the benefit to cost ratio. In gas engines the benefit maybe somewhat higher primarily because of lower compression and less carbon emissions.

My opinion is that synthetic does perform better then conventional oil but it's use is not warranted in engines where the only way to reduce particulate loading is to change the oil regularly. Where synthetic oils really shine is in sealed environments like a differential or a gear box. The comments here about how clean the engine is after synthetic use have nothing at all to do with base stock properties but rather the additive package contained within it. Most synthetic oils have a much higher detergent and anti foaming additive package and it's these detergents that keep the engine free of sludge not the use of synthetic base stock. Castrol is a manufacturer that uses a higher detergent package in their conventional oils. In testing, their oil performed as well as any synthetic at reducing sludge.

I use conventional oil in all my engines with the exception of my Prius Atkinson engine, but I still use the conventional oil change interval of 5000 miles. The Prius has a 3.25 quart capacity in the crankcase making synthetic use slightly more favorable. I use Red Line synthetic in all my gear boxes and rear ends. What other people choose to use and where, is their business. I just state what I know and do from a testing perspective. It's also worth noting that the reason diesel engines use such a large volume of oil in the crankcase is so the oil can adequately suspend the carbon particulates and because of the shear generated in the lower end from high compression ratios.
-Paul R. Haller-
__________________

__________________
Paul R. Haller is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 07-17-2012, 01:49 PM   #44
Senior Member
 
iRV2 No Limits Club
Join Date: May 2011
Location: Tempe, AZ
Posts: 1,833
Quote:
Originally Posted by szy View Post
Not at all .

I take preventative maintenance seriously , always have.

As part of that I do the research to find out what is the best product for the application at hand .

Paying more money does not mean better product "all the time" , hence I studied at length oil and its properties .

People think synthetic oil is some magical elixir that is a cure all for an engine that will make it last forever .

Synthetic oil has more myths associated with it than bigfoot

Most people just don't know that syn oil is made from regular crude oil base stocks, today a true syn oil is rare . It all goes back to Castroil oil Co. claiming its oil was a full synthetic oil and Mobil Oil suing them about their claim and losing . They all then saw a cheap way to claim their oil was a full synthetic oil while using crude oil to manufacture it and then still claim it was a full synthetic oil .

Not scoffing just passing on the information .
You're saying synthetic oil isn't synthetic because it's made from dino oil is like saying rayon isn't a synthetic because it is made from natural cellulose, such as cotton or even wood. Dino oil is the natural raw material used to make synthetic oil but it is no longer a natural material by the time it has been proccessed.
__________________

__________________
LadyFitz... is offline   Reply With Quote
Old 07-17-2012, 02:13 PM   #45
Senior Member
 
Francesca's Avatar
 
Vintage RV Owners Club
Join Date: May 2011
Location: Port Hadlock, Washington
Posts: 2,855
Quote:
Originally Posted by Paul R. Haller View Post
Synthetic oil was originally formulated for use in aircraft that had higher operating temperatures and an oil was needed that would not coke like conventional oil does at high temperature. Somehow that got translated to engines run cooler that use synthetic. So, does that mean some environments run cooler when using synthetic. The answer is maybe.

Heat is generated in direct proportion to friction. So, the real question is does use of synthetic reduce friction. Some tests reveal that synthetic base stock does resist shear at high pressures but most engines don't produce great shear values. Gear boxes produce high shear values and in testing running temperatures of gear boxes were reduced slightly by the use of synthetic base stock. Synthetic oil also has the ability to hold particulates in suspension better then conventional oil. Does that mean you can run longer change intervals? The answer is maybe.

Engines, and especially diesel engines have very high compression ratios. Compression also forces particulates past engine rings and into the oil where these contaminates are held until a specified drain interval removes them. While the base particulate loading in synthetic performs better then conventional oil, the engine continues to force particulates past the rings loading heavily the motor oil with carbon.

Synthetic oils are only slightly more lubriscious then conventional oil, especially at high temperatures, and their long chain molecules are somewhat more resistant to shear, in heavily loaded environments like engines, they perform only slightly better then conventional oil and run no cooler.

The bottom line here is it worth the additional cost? In most diesel engines that need 12 quarts of oil to fill the crank case or more the answer is no unless you put on an average of 250,000 miles a year on the engine. Most owners of RVs do not even approach this kind of use. Over the road, long haul truckers that put 350,000-500,000 miles a year on their rigs, perhaps can justify the benefit to cost ratio.

My opinion is that synthetic does perform better then conventional oil but it's use is not warranted in engines where the only way to reduce particulate loading is to change the oil regularly. Where synthetic oils really shine is in sealed environments like a differential or a gear box. The comments here about how clean the engine is after synthetic use have nothing at all to do with base stock properties but rather the additive package contained within it. Most synthetic oils have a much higher detergent and anti foaming additive package and it's these detergents that keep the engine free of sludge not the use of synthetic base stock. Castrol is a manufacturer that uses a higher detergent package in their conventional oils. In testing, their oil performed as well as any synthetic at reducing sludge.

I use conventional oil in all my engines with the exception of my Prius Atkinson engine, but I still use the conventional oil change interval of 5000 miles. The Prius has a 3.25 quart capacity in the crankcase. I use Red Line synthetic in all my gear boxes and rear ends. What other people choose to use and where, is their business. I just state what I know and do from a testing perspective.
-Paul R. Haller-
Another clear, well-reasoned, and thoughtful post from Paul- Especially as regards the "bottom line" assessment (in red above)!

Thanks, because:

This is a point of discussion at our house presently, though we don't have a motorhome. We do have several pieces of big equipment, though, and were recently approached by an acquaintance interested in supplying "better lubrication" for those machines. (Turns out he's considering buying in to the network that lets folks sell Amsoil.)

My husband the engineer was skeptical that the increased expense would be justified, and it would appear that his skepticism is well-founded.

Thanks again!
__________________
Francesca is offline   Reply With Quote
Old 07-17-2012, 02:29 PM   #46
Registered User
 
Vintage RV Owners Club
Gulf Streamers Club
Join Date: Oct 2010
Location: Indiana
Posts: 4,954
Quote:
Originally Posted by Paul R. Haller View Post
Synthetic oil was originally formulated for use in aircraft that had higher operating temperatures and an oil was needed that would not coke like conventional oil does at high temperature. Somehow that got translated to engines run cooler that use synthetic. So, does that mean some environments run cooler when using synthetic. The answer is maybe.

Heat is generated in direct proportion to friction. So, the real question is does use of synthetic reduce friction. Some tests reveal that synthetic base stock does resist shear at high pressures but most engines don't produce great shear values. Gear boxes produce high shear values and in testing running temperatures of gear boxes were reduced slightly by the use of synthetic base stock. Synthetic oil also has the ability to hold particulates in suspension better then conventional oil. Does that mean you can run longer change intervals? The answer is maybe.

Engines, and especially diesel engines have very high compression ratios. Compression also forces particulates past engine rings and into the oil where these contaminates are held until a specified drain interval removes them. While the base particulate loading in synthetic performs better then conventional oil, the engine continues to force particulates past the rings loading heavily the motor oil with carbon. Carbon is harder then steel.

Synthetic oils are only slightly more lubriscious then conventional oil, especially at high temperatures, and their long chain molecules are somewhat more resistant to shear, in heavily loaded environments like engines, they perform only slightly better then conventional oil and run no cooler.

The bottom line here is it worth the additional cost? In most diesel engines that need 12 quarts of oil to fill the crank case or more the answer is no unless you put on an average of 250,000 miles a year on the engine. Most owners of RVs do not even approach this kind of use. Over the road, long haul truckers that put 350,000-500,000 miles a year on their rigs, perhaps can justify the benefit to cost ratio. In gas engines the benefit maybe somewhat higher primarily because of lower compression and less carbon emissions.

My opinion is that synthetic does perform better then conventional oil but it's use is not warranted in engines where the only way to reduce particulate loading is to change the oil regularly. Where synthetic oils really shine is in sealed environments like a differential or a gear box. The comments here about how clean the engine is after synthetic use have nothing at all to do with base stock properties but rather the additive package contained within it. Most synthetic oils have a much higher detergent and anti foaming additive package and it's these detergents that keep the engine free of sludge not the use of synthetic base stock. Castrol is a manufacturer that uses a higher detergent package in their conventional oils. In testing, their oil performed as well as any synthetic at reducing sludge.

I use conventional oil in all my engines with the exception of my Prius Atkinson engine, but I still use the conventional oil change interval of 5000 miles. The Prius has a 3.25 quart capacity in the crankcase making synthetic use slightly more favorable. I use Red Line synthetic in all my gear boxes and rear ends. What other people choose to use and where, is their business. I just state what I know and do from a testing perspective. It's also worth noting that the reason diesel engines use such a large volume of oil in the crankcase is so the oil can adequately suspend the carbon particulates and because of the shear generated in the lower end from high compression ratios.
-Paul R. Haller-
Agree with most.. I would like to add that one should consider synth oil in extreme cold or hot conditions, or Turbo applications too.. I personally like to run Mobil 1 20w-50 in summer (especially this summer) and 5w-40 in winter in my Audi 2.8. We go from the 90's (100's) to -20F. Thats also my change interval, every 6 months Nov and April
__________________
Midniteoyl is offline   Reply With Quote
Old 07-17-2012, 09:28 PM   #47
Senior Member
 
Join Date: Mar 2005
Location: Northern Oklahoma
Posts: 3,674
Quote:
Originally Posted by SuperGewl View Post
Another non believer, I see. If you want proof then do it yourself. Take whatever vehichle you want find someplace level that you can set the cruize at whatever speed for let's say 1 to 2 miles and watch the tach and record the RPM's. Now take that some vehichle and replace the oil and filter with a good grade of 100% synthetic oil and run it for a few 100 miles and then take it to the same place you ran ealrier and perform the same test. You will notice a drop in RPMs at the same speed because the engine does not have to work as hard due to friction being less between those moving parts.
Let's see that is part of the reason for putting your oil in the engine anyway. But by using a better grade of lubricant the friction will be less, thus a lower RPM at the same speed.
In the 1,800-2,000 RPM range will I be looking for a difference of 10-20 RPM or in the 200-300 RPM difference with the use of synthetic?
__________________
wagonmaster2 is offline   Reply With Quote
Old 07-17-2012, 09:52 PM   #48
Senior Member
 
Ramblin's Avatar
 
National RV Owners Club
Workhorse Chassis Owner
Ford Super Duty Owner
Carolina Campers
Join Date: Aug 2011
Posts: 2,253
Quote:
Originally Posted by SuperGewl View Post
Another non believer, I see. If you want proof then do it yourself. Take whatever vehichle you want find someplace level that you can set the cruize at whatever speed for let's say 1 to 2 miles and watch the tach and record the RPM's. Now take that some vehichle and replace the oil and filter with a good grade of 100% synthetic oil and run it for a few 100 miles and then take it to the same place you ran ealrier and perform the same test. You will notice a drop in RPMs at the same speed because the engine does not have to work as hard due to friction being less between those moving parts.
Let's see that is part of the reason for putting your oil in the engine anyway. But by using a better grade of lubricant the friction will be less, thus a lower RPM at the same speed.
Chalk me up on the non-believer side.

Engine RPM enters the tranny, the tranny has a fixed gear ratio which means 1 revolution in = x revolutions out depending on the gear. The output side connects to the driveshaft. The driveshaft turns the differential at the rear end. The differential turns the drive axle at a fixed ratio, which turns the wheels and propels the vehicle at a fixed rate.

For a given engine rpm and gear, RPM is directly related to MPH. You can not get the same speed with fewer rpms without changing gears somewhere along the line.
__________________
2002 National Dolphin LX 6356
Workhorse W-22 chassis
Don't believe everything you think.
Ramblin is offline   Reply With Quote
Old 07-17-2012, 10:25 PM   #49
Senior Member
 
Wolfpack Fan's Avatar
 
National RV Owners Club
Join Date: Dec 2010
Location: Reno, Nevada
Posts: 851
Quote:
Originally Posted by Ramblin View Post
Chalk me up on the non-believer side.

Engine RPM enters the tranny, the tranny has a fixed gear ratio which means 1 revolution in = x revolutions out depending on the gear. The output side connects to the driveshaft. The driveshaft turns the differential at the rear end. The differential turns the drive axle at a fixed ratio, which turns the wheels and propels the vehicle at a fixed rate.

For a given engine rpm and gear, RPM is directly related to MPH. You can not get the same speed with fewer rpms without changing gears somewhere along the line.
X2 for that. Is that a Dolphin in your avatar?
__________________
Harley Ultra Classic (Geezer Glide) Rider, Retired US Army Paratrooper, fisherman, shooter. Proud to have served, proud of those that still do, or have done so with pride.
2005 National Dolphin 34'
[SIGPIC][/SIGPIC]
Wolfpack Fan is offline   Reply With Quote
Old 07-17-2012, 10:27 PM   #50
Senior Member
 
Ramblin's Avatar
 
National RV Owners Club
Workhorse Chassis Owner
Ford Super Duty Owner
Carolina Campers
Join Date: Aug 2011
Posts: 2,253
Quote:
Originally Posted by Wolfpack Fan View Post
X2 for that. Is that a Dolphin in your avatar?
Why, yes! As a matter of fact it is.

Bigger picture here.
__________________
2002 National Dolphin LX 6356
Workhorse W-22 chassis
Don't believe everything you think.
Ramblin is offline   Reply With Quote
Old 07-17-2012, 10:34 PM   #51
Member
 
Join Date: Nov 2011
Location: Layton, Utah
Posts: 69
I don't claim to know much about syn oil vs regular oil, but I had a 1986 Pontiac Fiero 2.8 L v6. I ran nothing but mobile 1 syn oil in it since day 1. At 67,000 miles it spun a rod bearing and trashed the motor. The oil was changed at 3,000 miles always. The only excuse I can give to the mobile 1 is maybe the car sat too long between uses. It took 18 years to give it 67,000 miles..
__________________
2000 Damon is offline   Reply With Quote
Old 07-17-2012, 11:00 PM   #52
Senior Member
 
Wolfpack Fan's Avatar
 
National RV Owners Club
Join Date: Dec 2010
Location: Reno, Nevada
Posts: 851
Quote:
Originally Posted by Ramblin View Post
Why, yes! As a matter of fact it is.

Bigger picture here.
Thought so. Looks good! We've got one too. 2005, 5320 we've had for a year and a half. Love it.
__________________
Harley Ultra Classic (Geezer Glide) Rider, Retired US Army Paratrooper, fisherman, shooter. Proud to have served, proud of those that still do, or have done so with pride.
2005 National Dolphin 34'
[SIGPIC][/SIGPIC]
Wolfpack Fan is offline   Reply With Quote
Old 07-17-2012, 11:24 PM   #53
Registered User
 
Damon Outlaw's Avatar
 
Join Date: Apr 2012
Posts: 364
I drive about 15,000 miles a year in my F53 motor home on one recommended/warrantied AMSOIL oil and filter change (about $67 + $20 for labor/disposal = $87). Ford and the other oil companies recommend/warranty 5 oil changes for their oil and filters. For a 7 quart oil change + filter, probably around $50 for a conventional oil change X 5 = $250. So I save about $163 a year on oil and filter changes.

15,000 miles at 7.5 miles per gallon is 2,000 gallons at $4 per gallon is $8,000. If I only gain 1% in fuel economy (most oil companies, government and consumer agencies quote 1-3% savings), that would be another $80 in savings.

So AMSOIL saves me about $243 a year, using fewer limited natural resources, and generating less waste and pollution.
__________________
Damon Outlaw is offline   Reply With Quote
Old 07-17-2012, 11:25 PM   #54
Senior Member
 
TurtleKent's Avatar
 
Tiffin Owners Club
Winnebago Owners Club
Freightliner Owners Club
Join Date: Feb 2011
Location: The Buckeye State
Posts: 492
Send a message via AIM to TurtleKent
Quote:
Originally Posted by SuperGewl View Post
Another non believer, I see. If you want proof then do it yourself. Take whatever vehichle you want find someplace level that you can set the cruize at whatever speed for let's say 1 to 2 miles and watch the tach and record the RPM's. Now take that some vehichle and replace the oil and filter with a good grade of 100% synthetic oil and run it for a few 100 miles and then take it to the same place you ran ealrier and perform the same test. You will notice a drop in RPMs at the same speed because the engine does not have to work as hard due to friction being less between those moving parts.
Let's see that is part of the reason for putting your oil in the engine anyway. But by using a better grade of lubricant the friction will be less, thus a lower RPM at the same speed.


Unless the laws of physics have changed since I went to college, a lower RPM at the same speed would be impossible, IMHO.
__________________
Kent & Sue & Pecos
2010 Allegro Bus 43QRP
Formerly 2004 Itasca Horizon 40AD
TurtleKent is offline   Reply With Quote
Old 07-18-2012, 06:57 AM   #55
Senior Member
 
Join Date: Mar 2012
Posts: 105
This would be a good test for MythBusters
__________________
Kunysz513 is offline   Reply With Quote
Old 07-18-2012, 08:16 AM   #56
Moderator Emeritus
 
RustyJC's Avatar


 
Texas Boomers Club
Join Date: Jul 2000
Location: Cypress, Texas USA
Posts: 8,854
Quote:
Originally Posted by TurtleKent View Post
Unless the laws of physics have changed since I went to college, a lower RPM at the same speed would be impossible, IMHO.
Yep, if the torque converter lockup clutch is locked, the gear ratios in the transmission and differential are fixed. Therefore, a given road speed in the same transmission gear MUST result in a given engine RPM unless there's slippage somewhere in the transmission bands, clutches or torque converter lockup clutch.

Rusty
__________________

__________________
2016 Ram Longhorn 3500 Dually 4x4 CCLB, 385/900 Cummins, Aisin AS69RC, 4.10
2014.5 DRV Mobile Suites 38RSSA #6972
Come join us on a TEXAS BOOMERS rally!
RustyJC is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 11:49 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.