I won! My mechanic says motor oil in tranny =good.

[scoobie]

I have the 1995 Mitsubishi Mirage Colt, three of them
I just had my "big tune up", which consists of new clutch, new rad, new brakes, new oil pan, new ball joints. I asked him to fill with my own "custom" tranny fluid. Guess what he said: he used to work for Mazda, and Japanese gearboxes like to run on 50% motor oil, 50% differential oil. He said the synchronizers work better in the cold with this mix, and Canada only gets one month of summer.

My "custom" mix consists of : 50% Mobil 1 extended 5w30, 25% Penn synchromesh, 25% semi synth Supertech 75w90. Everyone here was saying no,no,no,no - drain it out now, put in proper fluid -
but apparently i run the same fluid the Mazda dealer in Toronto puts in. (bonus, i put some MoS2 in for good measure). and I get my own mechanic's seal of approval (which honestly I did not expect in a million years - and he is a fantastic mechanic by the way ) My mechanic charges me 750$ for this "tune up", and I supply the parts and fluids and filters (+75$ to resurface the flywheel)

 

[deven]

What did you win?? A new tranny?? I am just kidding but I would sure love to see a UOA of this scoobie mix after 30k miles. What will MoS2 do? Someone here pointed out that you need some friction in the tranny so that the gears could catch rather then slip if its too slippery. I dunno

 

[aquariuscsm]

Who makes your Mazda`s tranny?

 

[scoobie]

It's a Mitsubishi 5 speed tranny, and it shifts and runs real smooth, the shifting is like butter, it goes up and down with no problems, even downshifting into first is a piece of cake.

I dumped in one can of Molyslip motor oil supplement for 2 gallons of home brew gear oil.

 

[aquariuscsm]

Originally Posted By: aquariuscsm
Who makes your Mazda`s tranny?


^^Sorry,I meant Mitsubishi`s tranny. I have no idea where I got the Mazda from :^P I was thinking it was a Getrag (like the 3000GT tranny).

 

[scoobie]

I assumed it was an in house tranny, but i dont know for sure.

 

[unDummy]

UOA it in 30k miles and post the results.

Seal of approval from anyone is meaningless.

Doesn't sound like a tuneup to me.

 

[mechtech2]

Some very famous Japanese cars said it was OK to use motor oil in the transaxle.
And many people did with no calamity.

But to deliberately use engine oil when modern dedicated gear oils are so readily available is not wise.