Joined: Thu Mar 22 2007, 08:13AM
Location: In the workshop
Posts: 1063
I'd like to add a bit of input on this subject. At present, I have 12 engines that I regularly service. 7 in cars, and 5 in garden machinery. I would love to be able to use the same oil in all of these, as it would save me quite a bit of money to be able to buy in bulk. A few years ago, I decided to try to do just what is asked at the beginning. Evaluate the oil to enable me to buy in bulk. The question was, how could I, as an average person, do this?
I reasoned that there were only two things that I could look at. Oil consumption, and oil pressure. I figured that if an engine lost pressure, it would likely go bang, and also if it burned oil it would do something similar. Reasoning that it was cheaper to see what happened with the garden machinery first, I tried various types of oil. Mineral, semi-synthetic, and full synthetic. Using a mineral oil, 3 of the engines (B&S) ran ok, and didnt burn any. Remember here that air cooled engines have a tendency to run hotter than liquid cooled. Using semi and full synthetics, all the engines burned oil. If I ran the engines on a 50:1 two stroke mix, these engines stopped using oil! That suggested to me that the oil was losing viscosity when it got hot, creeping past the piston, and being burned.
Moving on to the cars. The factory recommends a full synthetic for two of them. One, never used in traffic, loses oil pressure when it gets up to working temp. This is considered normal by the manufacturer, however. The other one, a VW diesel, uses oil. It even says in the owners manual that this is also acceptable. The third engine (in a diesel truck) takes a few seconds to build up oil pressure from cold if I use a semi synthetic, but the pressure builds immediately if I use a mineral.
If I use a semi synthetic in my BB Ford engine, if the coolant temperature goes up, the oil pressure goes down. Using a mineral, theres no noticable difference on the gauge under the same circumstances. I've only ever used a mineral 20W/50 in my Chrysler, so for that I cant really comment. However, the oil light does take longer to come on after switching off the engine than with the others. It also goes out quick, and tends to stay out even if it doesnt fire first time.
On to ZDDP. As I understand things, lack of this can cause two problems in older engines. One is the well known camshaft wear problem, the other problems is to what we call in Europe "small ends." ie, the piston pin bearing. No synthetic petrol engine oil will have high ZDDP levels. These are predominantly used in engines that have catalysers, and ZDDP kills cats! I dont feel that theere is any point in using a ZDDP additive in a synthetic. It oxidises quickly, losing its worth, and therefore requiring an oil change at mineral oil intervals. Synthetics being more expensive also hurts the pocket more!
Joined: Sat Apr 23 2011, 05:06PM
Location: Hawaii
Posts: 30
Any major boat yard or boat engine servicing company will be able to do an oil analysis for you.
It is very common to do on large boats because it is often cheaper to test the oil than to replace the 6-8 gallons of oil that their huge engines use.
Any Caterpillar, Yanmar, Detroit, Northern lights or whatever service company will be your best bet. They do it for heavy machinery as well.
They will take your filter and cut it open looking for sediment and such, you can do that sort of thing your self and take some cool pictures if you are up to it, they also send the oil off to a lab to be tested chemically for things like suspended metal and break down.
Joined: Sat Apr 25 2009, 03:08AM
Location: Out West
Posts: 626
Uncle Joe wrote ... I would love to be able to use the same oil in all of these...
Different engines have different lube requirements, and environment (average ambient temperature) can also play a role. The closest thing you will get to a one-size-fits-all motor oil is going to be one of the current crop of 5w/40 HDEOs. I think is interesting to note Dodge now specs the new MDS hemi's for a full syn 5w/40. That seems to support what I've been leaning towards for a few years, that if there is any oil that might be expected to do it all it is going something like a 5w/40.
I've been running it in my diesel trucks and Mopars (340 Duster and the 71 TnT) for quite awhile now, seems to be the right thing to do. <span class='smallblacktext'>[ Edited Mon Apr 25 2011, 09:34AM ]</span>
Joined: Sat Aug 19 2006, 05:03PM
Location: Ontario, Canada
Posts: 2919
I'm glad that Scott got something out of this deal. I have never actually received the oil nor filters that were promised when I signed-up for the promotion. I'm probably not actually eligible since I'm in Canada.
Joined: Tue Oct 11 2005, 04:38PM
Location: Grandville,MI
Posts: 957
I did some work for a friend of my Dad's and as partial payment he gave me some Pennzoil. At the time I was driving a 70 Duster with a 318. This was a GREAT running car (I wish I still had it) My friends used to say the only way you could tell it was running was by the fan going around. It NEVER used any oil. I changed the oil putting in the free Pennzoil, Man it ate the Pennzoil like candy!!! I went back to Quaker state and It never burned another drop again!! Now I use Castrol in all my vehicles but to this day I would NEVER use Pennzoil!!!! My friend goes to his local Pennzoil "quick lube" for his 2004 Jeep Grand Cherokee and been through 2 engines!!!! I keep telling him its that YEEPING Pennzoil but he says oil is oil it all comes out of the ground!!!
I know this really doesnt help you Nfury but I have good oil pressure and no burning with Castrol.
Joined: Mon Jan 22 2007, 11:15PM
Location: Phoenix AZ
Posts: 42
I use 5w30 Full Synthetic in all my cars, new old, big blocks and small blocks. Never had an oiling problem. All my engines have over 100K with no oil pressure problems, and excellent performance even when its 118* outside. Im also doing this to my 64 Caddy with its factory 429...
Joined: Tue Oct 11 2005, 01:33AM
Location: Calgary, Alberta
Posts: 5893
I would think 5W30 more suitable for Calgary where we get temperatures ranging between -40F and +90F. My Jeep uses 5W20 year around, a requirement of the engine warranty, and Jeep doesn't seem to make any adjustments for climate.
In AZ your temps are all shifted higher so I'd be looking at 10W40 just to make sure I've got a real good oil film on the really hot days. You don't really get, what I would call cold days. Lets face it, +30F is just a long pants day!
I'm hot and tired,,lol,long day at work,but I have to ask smokenmirror,,what's up with the avatar/pic,you having a bad day or what,,,how bout a pic of your car or a nice set of hooters,,something we can relate to,,not trying to be picky, but your pic seems somewhat out of place here,,lol.