[cschmidt1956]

I know this should be in the Drivetrain area, but we talk of efficiency and HP here so I think it's appropriate here also.

I did a Transmission Fluid and Differential Fluid change in my 2LT/RS yesterday. Pretty easy job and got to see some more of the engineering of this vehicle.

The Transmission takes 1.9 ish quarts of fluid and I used Royal Purple Synthetic for my change on this. The Drain plug on the M6 Aisin transmission does have a magnet in it and mine had minimal metal filings on it. I used the squeeze bottles and a hose to do the refill. I strained the old oil through a coffee filter and other than VERY fine metal like metal flake there were no observable problems.

The Differential had magnets on both the Fill and the Drain plugs. Slightly more fillings on these and the liquid was a lil darker. My fluid fill was Mobil1 75W90 LS and again I used 1 qt squeeze bottle for this fill also.

Took it out for a test drive and things seemed smoother. I was on the highway on a section that I travel a lot and reset the MPG. During a 20 mile drive at about 60-65, my MPG was at 30.9. This same stretch usually nets me about 27.9 Not sure if this is real MPG or not, but I think I will see a little gain. Should be changing the Oil in the motor next week and that will be Mobil1 also. Wanted to do this process in steps and see if my real world MPG increases and where it does.

The Royal Purple was $18.99 a Qt
Mobil1 75W-90 LS was $8.99 a Qt