I got fully synthethic oil put in my car about a week ago, the car seems to have lost some power even since then but the rides been a hell of a lot smoother, i can barely feel the gears switch since the oil change. Is fully synthethic oil suppose to slow the motor down or is there another factor that i'm overlooking?

 

What were the oil weights?

By the way, the engine oil has nothing to do with how the transmission shifts.

 

Yeah, the power of suggestion and your imagination. There's no way syn engine oil made any difference. Changing the tranny fluid might be noticable, depending on how long it had been.

I'm convinced if someone did a blind test and had 2 identical cars, one got syn oil and one didn't, people could not tell the difference.

 

if any thing the syn would make your car smoother and slightly more hp (we arent talking much, probably nothing that could be measured) due to less friction. there is no reasy why it would change what you feel with shifting since thts the Tranny! Its all in your head!

 

I also have thought my car shifts smoother since I recently went full synthetic but its all in your head. There is no reason for engine oil to affect the performance of a transmission. You are just paying more attention to little details and a possible change in weather/temp could easily affect the roughness of your shifts.

 

its not my imagination, the car use to jerk everytime it switched gears, now it stopped doing that every since the oil change but maybe its the weather change as you have suggested. The temperature averages between 90 and 100 around here lately so that may be the case. Also, no need to get all excited, i was just merely asking a question, we are all adults here aren't we?

 

The curent national heat wave just might be diminishing the cold shifts that
plaque this car. In cooler months I notice hard abrupt shifts for the 1st 1/2
mile or so. With the car being hot right now from the get go I am not seeing
that anymore. I'm sure it will return once there is a cool morning.

/Steve

 

Its the placebo effect...

 

Yeah my car has 100k miles and I just switched to synthetic oil. When I first started the car it seem to be quiter and the gears switched more smoother, I also added an engine treatment for $20 from autozone in that sparky silver looking box, starts with X....

 

If your tranny shifts wierd..take it in to the dealer..have it checkup. I think you are talking about the transmission oil. Not motor oil.