“I may be an old geezer, but I’ll go along with the times.”
Triedaq gives a brief history of evolving car and oil technology and it illustrates how some old-fashined ideas still stick in some people’s minds. Some advice from old geezers (or young punks) who have not gone “along with the times,” may not be the best.
Pumping the accelerator while starting a car or revving the engine while turning it off are a couple more examples that go along with advice about using heavy weight oil (much higher than manufacturer recommended) for aging cars.
Sometimes “if a little is good then a lot is better,” isn’t better.
Racing engines were built quite loose with much greater clearance on bearings, pistons, etc., and used heavy oils and high volume pumps to keep everything together. Somewhere the 20W-50 “racing” oil got popular with wannabe hot rodders and those who thought that racing oil must be better than just plain oil. Well, that’s how it appeared to happen down south. And in warm weather the heavy oil didn’t seem to make much difference especially in big American V-8s.
Let me add a couple other thoughts on using heavier or lighter oil than specified. I have a 1978 Oldsmobile Cutlass with the 260 cubic inch V-8 engine that I purchased new. The owner’s manual specified either 10W-30 or 10W-40 oil. I believed that the 10W-40 offered better protection, so that is what I used. However, I kept having problems with carbon build-up and pre-ignition (engine ping). I would pour one can of Casite Motor Tune-up in the gas tank and feed another can of Casite through the carburetor and then run the car up to a highway speed in 2nd to burn out the carbon. I had to do this treatment about 3 times a year. Someone called into CarTalk with a similar problem. Tom and Ray suggested that the 10W-40 oil might be the problem. I switched my Oldsmobile to 10W-30 and my carbon build-up problem disappeared. Apparently the polymers that increased the viscosity range in certain brands of 10W-40 casued the problem.
On older 1 cylinder air cooled lawn mower engines, 30 weight was specified. I know of a couple instances where a person reasoned that 10W-30 oil should be the same, used the 10W-30 and the connecting rod bearing let go. I think that a 5W-30 synthetic oil might be o.k. in these engines, but I’ll stick with the straight weight 30. I have had the mower since 1988 and had no problems.
Here in the mountains of Mexico, the stores mostly stock oil like 20W50. It is not that hot here. 95 degrees is very unusual. I have no idea why they think they need something like 20W50. I suppose it is an “old husband’s tale?”
Just bump it up one weight from what they want you to use they do cafe and run thinner to get better gas mileage so just to be on the safe side just go up one wei
ght.
Old thread. Just use the recommended weight. Lots of places hotter than Florida (engines don’t care about humidity), all should use what’s recommended.
Gee, I can’t believe I missed this one seven years ago. Musta been busy. I’ll defer to experts but the question I have is how does the engine know it’s 100 degrees in Florida or only 70 degrees in Iowa? The engine starts cold at about the ambient temperature which may be anywhere from 10 below to 100 above. Then it warms up to operating temperature of 220 or so. It will continue to run at that 220 temperature until shut down. So what difference does it make if it is 100 degrees out or not? The engine is running at 220. Now with coolant in hotter temps, there can be a reduction in the ability to cool the antifreeze a little in hotter weather but still are only talking about an additional temp of maybe 20 degrees unless the engine fries at 280.
So yeah, use what the book says regardless of what they do in Mexico.
Some one mentioned this earlier, the coolant temperature doesn’t control the oil temperature - the oil depends on air flow over the pan for some of it’s cooling so on a day when the air near the pavement is 120F it oil will run hotter than a day when it’s cooler.
We’ve followed the mfgrs oil recommendations for decades with several cars having tight engines beyond 220,000mi., no oil consumption or lubrication issues, using quality conventional oil changed at 4000-5000mi. (Synthetic used where required). A car that obviously is heavily worn might be a candidate for heavier oil, but there could be trade-offs with how well the oil pump can deliver it and how it performs in hydraulically operated components.
Well, now that this thread has been revived yes since I matured in the late 60s, the lower viscosity requirements seem too low but the manufacturers engineers know what they are doing. My F150 4X4 takes 5W-20, that is what it gets. I do change early, at around 20% according to the OLM.
The one thing I am not good at is checking the oil level. Though the truck is totally stock, the location of the dipstick makes using a small stepladder a necessity.
I think people get hung up on the cold start part of the multi-weight oil. It might be acceptable to use 5W20 instead of 0W20 in a consistently warm climate, but it can freeze overnight as far south as Alligator Alley.
I have an old EXXON tape called “The Cold War” detailing the problems with very cold starts.
They have a Ford Escort with 10W30 mineral oil and start it up in a lab with -35F temperature. After several minutes the engine starts smoking as the thick oil is not reaching the valve gear. Considerable damage was done after several of these cold starts.
Those of us who have lived in these regions use block heaters when possible but also go to the widest grade of multi-viscosity oils to both ensure safe starts and good protection once the car is warmed up.
This EXXON tape then showed their 0W30 synthetic under the same conditions with the same car. No problems here.
I’m curious re the smoking due to the thick oil not reaching the valve gear. I Googled EXXON Cold War and didn’t find anything. Escort engines had hydraulic lifters and if the oil was too cold to pump several lifters would be stuck fully extended while others would be lacking oil and clattering and if smoking it would seem to be friction on the bearings or on the cam lobe to follower interface.
No doubt -35* F is off the charts for me though. My record low dealing with cars was -2*F and most people were lucky their engines wouldn’t start considering the damage done to some that did.
You haven’t lived until you take your diesel out pre-dawn cross country when it’s -24 out, hoping the fuel doesn’t gell, leaving you stranded and dead. Kinda like being on a tight rope with a fine line between being alive or dead.
The tape as made by the Canadian division of EXXON (Imperial Oil), when they were introducing cold weather synthetic oils. Prior to that Shell had introduced their “Syn-arctic” which was a synthetic blend with a pour point of -50C. We’re going back to the 70s here. That was before Mobil1. The smoking in the experment was likely camshaft bearings not getting oil. Many other parts would not be getting oil either.
In today’s engines most have the valve gear actuated and adjusted by hydraulic pressure form the engine oil and the oil flowing properly is doubly important
If you are in doubt about any oil, check the pour point and the “Borderline Pumping Temperature”. Then compare with your lowest expected temperature. Our lowest last winter was about -36F.We have an electrically heated bird bath in our yard. It’s made in Minnesota and performed well for 5 winters now!
We often spend time in a mountain lodge in the winter. Many have no outlets for block heaters. On a cold morning it can be soo cold that the car door locks don’t work and the gear shift is only moved with difficulty…
