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For the Toyota MR2 -spyder; Spyderchat
For the Honda K20; k20a.org
mazda 3: mazda 3 Revolution
Hyundai Ioniq forumThey have determined that ATF change is not required to assure a 100,000 mile reliable life (the North America warranty period), so it is not recommended. Also you have to be careful in doing the fluid change. You have to be very sure not to introduce even small particles of dirt into the system and all fasteners and plugs have to be installed per the torque specs. Use only the proper sealants if the transmission pan has to be dropped. Before attempting an ATF fluid change make sure you completely understand the procedure and have the proper tools. If you are not careful, you can do more damage than good. In my opinion, if you are a very good and careful mechanic, there will be an overall (long-term) benefit to doing an ATF change at 50-60K miles
I have seen the 30 K interval in other owner’s manuals. There is really no good reason to change an OAT antifreeze more often than once per decade. They might be assuming you won’t dilute the pure antifreeze with distilled water or might assume you will not use the OEM spec antifreeze. Break-in has no effect on antifreeze.
regarding ATF; If I wanted an automatic transmission to last for 200,000+ miles, I would change the fluid at 50 – 60K miles intervals. I would do it myself or a very well-trusted garage.
The Owner’s manual is correct about the coolant. Modern coolant uses completely different anti-corrosion chemistry than the green stuff we used through the ’80’s. It is called Organic Acid Technology and truly last 10+ years. No advantage changing it early.
Regarding transmission fluid. I assume you are referring to automatic transmission? I would read the owner’s manual carefully and if there is no trans fluid replacement interval specified under severe-service, you should be fine leaving it unchanged for 100,000 miles, which in the US is the warranty period. If you keep it longer, I would change the fluid. The reason you can follow the manufacturer’s recommendation not to change in a modern car is that the transmission design and the transmission fluid are all much better engineered than in the past.
Dave
It is difficult to say that all first year major components are to be avoided. product development processes are improving all the time. droth6189@gmail.com
In theory, every major component in a vehicle is thoroughly tested under severe conditions before entering production, but these tests are accelerate tests that try to duplicate many years in-service. So they are not perfect tests. The net effect is that the first generation of any new engine or transmission (the most complicated powertrain components) will tend to be less reliable and durable than subsequent versions.
With CVT’s, running at high power levels is stressful because it puts more heat into the friction surfaces and the special CVT oil, so I would certainly expect any CVT to last longer if it is driven easily than aggressively. Every CVT transmission has a maximum torque limit.
The main reason for Nissan CVT failures is that when introduced, they were relatively new technology. CVt’s have been continually developed since the first generation were put in production, and the newer the model year, the more reliable they are.
The reason why many Nissan CVt’s feel like there is a lack of torque (I think you really mean acceleration) is that they are calibrated for best fuel economy, and that means keeping the engine rev’s as low as possible for current speed and load. The other reason is that most of the Nissan’s are relatively low Power/weight vehicles, so in order to get a good level of acceleration, the transmission has to shift ratio to one that lets the engine get into the high power region. Remember that performance is proportional to Power/weight, not Torque!
If you physically can not turn the key in the ignition it is likely due to the steering column interlock. This is a feature designed to prevent vehicle theft by preventing a thief from being able to steer the car even if the ignition is “hot-wired”. This can happen from either a worn or improperly made key (like a duplicate key). More common is that you can get around this by simply moving the steering wheel back a forth a little bit while trying to turn the key. If this works, the problem is just the friction in the steering column interlock due to a little bit of load on the steering wheel. It should not take much pressure on the steering wheel to allow you to turn the key.
As engine oil approaches and goes beyond its normal service life several things happen that make it unsuitable for the engine:
1) The viscosity (oil thickness) changes. Continual exposure to heat tends to thicken the oil and it eventually becomes out-of-spec for your engine. this can increase wear in the engine
2) The detergents that are in the oil get depleted and the things that contaminate the oil continually (like soot) build-up; but the worst problem is that the detergents that are supposed to prevent sludge formation in crankcase stop working. The effect is that the oil starts turning into a grease-like product that will not flow to your bearings
3) The oil becomes corrosive, because the anti-corrosive additives wear out. This can lead to severe wear
4) In cold weather, especially with many short trips, the oil will become diluted with raw fuel and liquid water. This really degrades the lubricant properties of the oil.As to how long you can go with old oil, generally 7 months or 7500 miles, but the only correct answer is to read your car’s owner’s manual and find the answer in the maintenance section
The basic answer is Power/Weight ratio correlates to vehicle performance
The energy used to run the compressor in a turbocharger comes partly from the wasted exhaust energy (part comes from the exhaust pumping work), so the energy needed for boosting is partly free. The turbo does create extra back-pressure, so that does have penalties (parasitic loss and worse knock resistance at high power). The energy used to run the compressor in a Supercharger comes 100% from the crankshaft, so it is all parasitic loss and all of it contributes to higher cylinder loading and worse knock resistance. The net result is that turbochargers can provide more boost more efficiently than Superchargers.
There are 2 things that can be bad about too frequent oil changes:
1) If you don’t manually refill the new oil filter before installing it, the first startup after the oil change is with an empty filter and that means the engine will run without oil to all of the bearings for a few extra seconds while the filter fills up and the air in the filter gets pushed through the oil passages. Won’t kill your engine but something to be avoided or minimized in the interest of long engine life.2) I did not believe this until I saw this with my own eyes, but under normal service, an engine can look beautiful inside after 250,000 miles with just 7000 mile oil change intervals. Bearing wear, piston ring, piston skirts all looking pretty good.
I know many European drivers who rarely change oil more frequently than every 7,000 miles (some even 10,000) based on the vehicle maintenance minder, and are past 200,000 miles. So unless you are driving severe conditions, 3000 mile oil change intervals are just a waste.The best answer is to read the Maintenance section of your owner’s manual for the answer. They will usually list a mileage and time for change. The more general answer is; if you are using the old coolant formulation (usually green) that contains Silicates as the the anti-corrosive technology, you should not leave it in longer than 4 years. If you are using the newer Organic Acid Technology (OAT) coolants (usually orange or red), they are truly good for a 10-year stint.
