I've been sitting at my computer all morning researching this question. Would have been more fun in the shop.
I want to share with you what I've discovered, and you can help decide what we should do, if anything.
I've been talking to the technicians at Mobile:
To: Mobil One Technicians
We are members of Model T Ford Club of America and the Model T Ford Club International, both International in scope and representing perhaps 100,000 Model T Fords, many operational. For these memberships, we are trying to identify the best possible Engine Oil currently available. There is little question that any motor oil available today would be far superior to oils available in the 1909 -1927 era. However, the Model T Ford does have some unique requirements. First, it has a flat tappet valve train and while the rpm and spring pressure is low, we feel a high level of ZDDP is desirable to provide minimum wear. There are, however, in our group, many modified engines with higher valve spring pressure. The Model T Ford engine, transmission and steel disk clutch all share the engine crankcase. The transmission is bronze bushing technology. Because the cylinders are water-jacketed only on the top inch or so, and there is no water pump, the engine likely runs hotter than most. Because of the low quality of fuels available in the era, these engines came from the factory with an extremely low compression ratio of 3.98 to 1. Today, many enthusiasts use higher compression heads rated at 6 to 1 and drive sustained speeds of higher than 40 mph. Speeds in the era were commonly 25 to 35 mph.
Using your Motor Product sheets for a comparison of Mobile Motor Oils, we selected Mobile 1 Racing 4T 10W40 Motorcycle oil with ZDDP at 1600 PPMs and designed to provide the proper frictional characteristics necessary for wet clutch engine/transmission systems.
Our questions; first , do you agree with our selection? And next, where do we buy this oil? Our preference would be at our friendly Walmart store, and in the 5 quart jugs. Is this possible?
They would not send me a written message, but over the phone told me the selected Motorcycle Oil is a perfect fit and we could buy it at AutoZone. I called several, and it is available at about $9 a quart. Now, this stuff is Mobile 1, full synthetic. Since we don't need synthetic, I hope we find a conventional oil with the same charactistics.
Then I happened on to the following website:
I think the info is great, and points out a couple of things we had not considered. The Model T wet clutch and the fact that friction modifiers are being added to the SM API rated Automotive oils.
Please look it over and tell me what you think.
The article also points out that motorcycle engines turn many times faster than automotive engines. And so, the rules for automotive based oils don't necessarily apply to motorcycles. Compared to a Model T, motorcycle engines turn faster by an even greater factor. Perhaps a factor of 10 or more. In my thinking, that makes the rules for motorcycle oils even less relevant for a Model T as they are for a modern car.
The wet clutch issue is perhaps the only real similarity. I think however, the differences outnumber that interesting relationship. Additionally, the clutch of a motorcycle is used differently than the clutch in a T. Ideally, a T clutch should experience little to no feathering, (depends on the technique of the individual driver), while the MC clutch would experience a great deal of it, and at very high revs.
I think we'll know more about this issue when and IF engines begin to wear rapidly due to lubrication issues. (Not oil level, but oil quality!) Of course, every worn engine will now be blamed on oil as if they would have lasted forever if only we had oddles of zinc. So far, I'm not convinced it's been a problem. More of a Y2K panic.
Thanks for your efforts Fred!
I am sure the motorcycle spec conventional oils would be fine in a Model T engine, much better in my opinion than any synthetic motor oil. Overkill for most Model T's, but probably a safe bet in your Fronty equipped racer.
Wow that was a lot of info to absorb , Mobil 1 V twin sounds ok for my environment , but seems to lack the adequate proportion of ZDDP , and how much will l spend to buy a better oil that may or may not work any better in my engine whilst travelling at say 45 mph , l dont know , but if l can buy 6 litres of oil from my local car parts supplier for less than $ 20-00 , and change it regularly , say every 6 months, l am hoping that will serve the same purpose, life lengthening, BUT more importantly as a mass of owners , cant we demand an from an oil company whether it be Mobil, or a smaller company, an oil that will serve every T owner at a good price to keep us coming back for more ??
Something to think about
Fred & All :
Here's the link to the Mobil 1 Motorcycle oil sheet .........
Thanks for your interest & effort.
Thanks Fred for all your research on oil to use in our Model T's. I think the Mobil 1 V-twin 20w-50w oil sounds pretty good. Even if it cost $9.95 per quart, its cheaper than fixing an engine for failed parts. A Model T engine and transmission are so similar, it seems to me.
Let me be one of the first to convert to the Mobil 1 Motorcycle 10W40.
I'll let you know if there is any change in band or clutch function, starting or running problems.
I've used Mobil 1 before & have the confidence that the motorcycle formula will offer better protection.
Oil is the cheapest service replacement item on your car, why not use the best to protect your investment.
Check out the FAQ on the Mobil 1 web page:
Click on the "chart" link for ZDDP levels in Mobil 1 products.
Fred's recommendation of Motorcycle 10 W 40 has twice the ZDDP levels of regular SM new car oil. ....plus the added advantage of higher temperature protection.
Listed racing oils are not for street use, but will be available this spring. Have more ZDDP than motorcycle formulation.
Mobil's necessary disclaimer, use at your discretion & application.
I have been using Mobil 1 in our 13 touring since rebuilding the engine over 10 yrs ago.
After 5 years, I had to disassemble the engine in order to mill (Deck) the block flat. During disassembly, I found that the cylinders still had hone marks and the main and rod bearing were not fully seated, still having the machining marks. I was unable to remove any shims during reassembly.
From my own and the experience of others that are using synthetic oil in their T's....using synthetic oil is a good choice. Yes, synthetic oil is more costly compared to conventional oil....however, I consider it cheap insurance compared to the cost for engine rebuilds.
Page 24 in the current (2008-2009) MAC's Catalog lists a 4 oz. bottle of an engine oil additive called ZDDPlus that they recommend adding with each oil change. Part of their claim is that this additive "Restores ZDDP to the optimum level, which existed when your classic car was designed". (???) On one hand, I like the idea of a simple and inexpensive way to restore ZDDP level to any oil, however, I don't think ZDDP existed during the Model T era. On the other hand, if major oil companies have been prohibited from exceeding a certain level of ZDDP in their oil, how can this ZDDP additive be legally sold if it really (IS) ZDDP. (???) Kinda' makes me wonder about their entire claim for this stuff.
Fred, Les & All:
Changed oil today, went for a ride. Temps in the mid 50's, sunny, great day in coastal central New Jersey.
Stopped in Lakewood & Jackson to see friends. Engine ran well, Watts clutch & wood bands worked as before.... smooth.
Engine ran good, maybe a little peppier.
Round trip about 60 miles
Cost of Mobil 1 10W40 4T Motorcycle oil locally was $10.35 a quart. I needed to change the oil anyway. Extra cost above regular Mobil 1 was only $3.00 per quart. These are my local prices in central New Jersey........ your area will vary.
Hand cranked & starter starts were no different. Easy.
Now have the extra protection of high temp stability with extra ZDDP compared to regular car formula Mobil 1 .
Any changes will be noted
After all that reading I still see nothing wrong with going to Wallmart and getting The lower priced Accel 10-40 that is SF rated.
Or Just using whatever weight of SL oil you like and a 12 oz. bottle of the cam break-in additive for $11. Maybe a 1/2 bottle on well broken in stock T engines.
Or use whatever SL oil you like and a can of motorcycle oil.
Call it "Peace Of Mind".....those of us that use Synthetic's undoubtly pay more than others that use conventional oils. I happen to be one of those that still changes the oil in all our vehicles, both new or old. At work, I often hear how much a co-worker spends on what should have been a simple oil change at their dealer's. The higher cost that I pay for Synthetic oil is a brgain by compairson.
I think this is great. Several years ago I asked about slick50 and other additives and the effect on bands and clutch with no response. The question was - will the bands still grip the drums in a "super slick" oil bath? I'm glad to see results of actual tests. Anyone try Zmax yet?
I have only used Castro Syntac & Mobil 1. I started out using Castro Syntac and switched over to Mobil 1 because Costco stoped carring Castro. I could not tell any difference in performance between the two brands. Never had any problems with bands or clutches slipping. Also, I have not used any "Blends" only full Synthetic.
When I pulled the engine down to deck the block, I replaced the driver cam with a new Strip 280 cam shaft. Set the valve lash at .010 and have not done any adjustment sence. The first tour after was Knab Ut. & The T performed well even over Trail Ridge. When the engine was down I also balanced and trued the transmisson. What a difference that made....very smooth.
Slick 50 has Teflon and Molybdenum powder in it. Tests by various automotive magazines have proven over and over that the solid matter is captured in the oil filter, often blocking it completely. Very evil stuff, does not do any of the things stated on the label. Slick 50 is the subject of a warranty denial warning letter by General Motors. What ever you do, do not use Slick 50 in anything. It is bad news.
Thanks Fred and others for your research.From what I can tell a good engine rebuild is exspensive so that makes the oil cheap insurance.
I catch alot of crap from folkes because I still use the dang near 4 dollars a quart castrol 20-50 in my dailys.308,000 miles and still kicking in 1 of my cars,that tells me good oil and regular changes are worth it.
The rest of the car is falling off the frame,but that engine,runs fine.
I am doing my first oil change on my '25 roadster...do I still use a gallon of kerosene to flush the engine as the manual states???Seems I did this in the forties, but not since...Thanks for your input...Fivver Jack
The oil is really black...
I fully understand your effort to use a domestic brand. but UK based Castrol oil offers a line of "Classic" oils - in true singlegrade 20, 30 and 40 among others.
I use Castrol Classic 30 in my model T.
So some oilcompanies have adressed the potential of the "Classical movement".
(Useal disclaimers applies)
Being a long time motorcycle rider and short time T owner I would say motorcycle oil is overkill. Motorcycle oil is designed for fast reving and high rpm's as not to create foam in the engine case which is a problem with car oils, but before they invented motorcyle oils ppl used the standard car oils for years without any problems. I use Amzoil fully synthetic in my high performance motorcycle engine but when my dad was building Honda race motors in the 70's he swore by Valvoline because he said the engine was always clean as a whistle when he tore motors down after using. Since modern day oil doesent readily break down it just gets dirty I would stick with regular oil changes and cheaper oil. Amzoil says there oil can go 10,000 miles compared to the others that say 5,000 and the quick lubes that say change it every 3,000. Oil companies are there to make money and I dont trust any of them to be honest.
You said it yourself.... motorcycle oils will not create foam. In a splash type system, why wouldn't you want to use an oil that does not foam ???
Been using Mobil 1 Motorcycle oil for 18 months now with no adverse affects, no band chatter, and the oil formula has the full complement of anti-wear ZDDP of the oils from the '70's. Good for my money.
Correct that time period to 10 months.
I agree with your want for what some may consider overkill, but I don't think you have to spend $9/qt. to get what you are looking for.
Auto-Zone stocks both Valvoline and Castrol 10W-40 Motorcycle oil which like the Mobil 1 has no API service designation "S whatever" and has all the ZDDP you want. The Valvoline is $4/qt the last time I bought some (also marketed as ATV oil) and the Castrol is $5/qt. I'm cheap, so I run the Valvoline in my gearbox-in-the-sump Mini and I refuse to pay $12 for a bottle of ZDDPPlus.
So, for the same money you are spending, you can change the oil twice as often which is a good thing for filterless applications like the T.
Some motorcycles run at 7000-13,000 rpm's at speeds exceeding 150 mph with a wet clutch spining at the same rate being slipped and abused and a high pressure oil system that doesent need to suck in a bubble, If you drive your T like a 1800cc crotch rocket then you might need it. For a lot of years there was no such thing as motorcyle oil and they ran fine on what was sold off the shelf at the local auto store. The cheaper brands of oil like the walmart brand are bottled by the same companies like Mobil or whoever it is but they dont contain the same detergents to prevent sludge from what I understand. Its like the debate I have had about using fuel stabilizer, lots of ppl use it in there boats and lawnmowers and other small engines and it works great! Well I dont use it if I intend on using that particular machine in the next 10 months and it also works great. (fuel doesent go bad in that short of a time period) If it works for you and you believe in it than keep using it.