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Mobil 1 Full Syn VS Honda Motor oil, Semi Syn?

Is Mobil 1 Full SYn help with gas mileage especially in the cold months (CA winter)?

I currently have Honda Motor oil Semi Syn - rpm goes high before advancing gear on my 99 Acura Integra AT.
Previously I had Mobil 1 Full Syn - I remember gear advances much earlier.

Any thoughts?

As long as the weight is the same it makes no difference. Your engine will see no discernible rpm gains or losses. Maybe your tranny is slipping.

Update: Honda Motor oil Semi Syn

But I do see a different as to how the gear shifts

I agree, I think you have a tranny problem developing. I just went to Mobil 1 instead of Acura semi because it was the same price or less for the Mobil and figured mobil was better. But I only did it because of the 0-20 weight, otherwise I had just used Dino.

@Bing did u notice any difference with Mobil 1. I think that it served me better than even Valvoline Full Syn.

With Mobil 1, I remember gears just advances so easily.

The issue I am experience is during cold start, the gear takes a while to advance - there is no slipping at all. Tranny fluid (acura) was just changed in the summer. I have been good at changing this fluid every 12k - the car has only 105k.

Type of oil has nothing to do with the shifting of the transmission. I know some GM cars, the ECU is actually programmed to shift higher in colder conditions, could be normal… How cold does your part of California get? When I hear cold, I think 0-5F. Either way, you seem to be good with the trans fluid changing and if the gear changes are still smooth and quiet, I wouldn’t worry about it.

As far as oil brand goes, it’s all basically the same in my book. You’ll never know the difference as long as they’re the same weight. Just don’t use synthetics if you’re manual calls for standard motor oil

Nope, never noticed any difference because never used anything else except one oil change with Acura semi.

Overnight cold conditions in CA expand the list of choices for engine oil viscosity. Honda’s 2012 OM specifies 0W-20 for anywhere, in an attempt to get the magic 40MPG in the EPA highway mileage test (they just missed with 39).

Honda automatic transmissions, on the other hand, are very specific on the fluid used. Just because the bottle says …meets Honda spec…, if it’s not Honda fluid, it doesn’t meet the spec.

Is Mobil 1 Full SYn help with gas mileage especially in the cold months (CA winter)?

I a word…NO.

@MikeInNH Agree; the synthetic helps with easy starting in cold weather and provides good film strength with hot operation. Fuel mileage should not differ by any measurable amount, compared to a similar weight dino oil.

Most likely the delayed shift is normal when cold. Manufacturers are doing this to warm the engine up quicker for emissions reasons.

I know a guy (engineer I worked with) who switched all lubricating fluids over to synthetic. After months of keep records…he concluded his gas mileage increased by about .2mpg…Which means virtually no change.