Waterford Hills Road Racing  Forums

Miata Transmission Differential Service

Looking for recommendations? Have one to give?

Miata Transmission Differential Service

Postby r.ranville » Thu Jun 05, 2014 11:54 am

I am ready to do my trans. turret rebuild and change trans and diff fluid. In a posting I saw on-line a guy said his diff fluid was really black and practically clumpy. I'd be surprised if either fluid has been changed in this car - with about 62,000 miles; if this stuff comes out really dirty, is there any cleaning that can be done, short of dismantling them?

I bought all OEM parts from Arlington, who has been very helpful.
You might as well go fast; it'll go by fast anyway.
Posts: 120
Joined: Thu Jun 21, 2007 7:29 am
Location: Flint

Re: Miata Transmission Differential Service

Postby tyurkunas » Mon Jun 09, 2014 8:51 am

You'll need to "slightly" warm-up the transmission internals before changing the fluid. Don't get it too hot or it'll be really difficult to change cuz' you're probably gonna' spill some fluid on the ground or yourself.
Also, be sure to loosen the upper (fill) plug before you loosen the lower (drain) plug. Too many guys have drained the tranny - only to find out that they couldn't get the upper fill plug off.
Attach a funnel to a long hose .... snake it through the engine compartment along the firewall to refill the fluid. This stuff is gonna' be ugly and will stink like hell - but that's normal.
Lastly, there's a pretty good step-by-step on http://www.Miata.net (Garage section) on how to change the tranny & rearend fluids. Plus, you might want to search "Miata tranny fluid change" on YouTube .... there are several good videos there.

Tom Y.
Posts: 71
Joined: Thu Jul 05, 2007 11:03 pm
Location: Ypsilanti Twp., MI

Return to Advice Column