Should a manual tranny engine have different oil than an auto tranny engine?

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The other thread was locked before I finally had a chance to ask the real question I was trying to get to.

You see, first I wanted to establish that identical engines connected to manual transmissions or automatics wore differently and had different stresses placed upon them. I think there was pretty good evidence in that thread that they did.

So the question then: How should engine oil recommendations differ as to viscosity, etc., depending upon transmission type?
 
That's something which I don't think would make any real difference. Manual tranny drivers tend to downshift more than auto drivers and the compression braking places a little more strain on the engine's center main bearing, but again I don't think it's enough to matter as far as wear or the oil is concerned. Autos on the other hand have more of a constant load I suppose, but a lot depends on the individual driver to make a broad generalization. With my size 12's I can heel-and-toe and match rpm in almost any vehicle. A wise man once said, "It's a lump of metal, not a holy relic fer crissakes".
 
Well, if it helps your assumptions, I don't engine-brake, I tend to coast up to stops and kinda bump the shifter into neutral from twenty on to down to 0MPH at lights and whatnot, and use the brakes to stop the car. Brake pads are cheaper than clutches and main bearings. The engine is for accelerating, not braking.

But that's just me. I see all kinda of bikes and WRXs, etc. whining the revs to redline coming to a stop. Sounds very destructive. Kinda like fabric tearing.
 
I agree as well to use the brakes insted of the engine when coming to a stop. Manual cars do put more pressure on the thrust bearings than autos. Its always best to stay off the clutch only when you need it. Oil weight does not change from a manual to an auto.
 
if you lug a stick all the time you might consider a slightly thicker grade.

automatics will downshift, spin more, and keep pressure up with a slightly thinner viscosity.

I'm talking about "it's between winter and summer, I'm on the fence between 5w30 and 10w30" differences.
 
So, when coming to a stop in a manual - just put the shifter in neutral, let off the clutch and cost/brake to a stop? Parents & Grandparents have always shift down to "save" brakes.

In the city - especially stop and go - downshifting can be a majority of the clutch usage. So I imagine that using brakes only would be a good thing...
 
As was pointed out above, brakes are much cheaper to replace than clutches. It's definitely better to stop with the trans in neutral.
 
I read about a question similar to this decades ago. IIRC, the answer was that engines mated to manual transmissions show more wear in both thrust directions, where engine mated to automatic transmission show wear in one thrust direction only.

I think what was meant by that answer is that both engines will wear in the "acceleration" direction; manual transmission moreso in the "deceleration" direction because of the mechanical linkage (clutch) to the engine. In other words, automatics tend to free-wheel when you take your foot off the gas.

Remember, this explaination was before the use of converter clutches.

As far as using different oils for different drivetrains, I don't think it matters.
 
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