DIY: Transmission and Differential fluid replacement
 

Note that this is NOT my own DIY. But I feel this is so useful it belongs here in the DIY forum.

Credit for this excellent DIY goes to forum member "jdl" - and KUDOS to him for a superb DIY! It was first mentioned in this thread, which is a good read and has lots of info in it too.

http://www.5cats.org/rx8/trans_diff_refill/

Sweet ! I'm doing mine next week

Easy enough. Are the fill plugs located such that you can't overfill? Or do I have to measure our the liquid?

I did mine...the fill plugs will let you know when the tranny/diff are full...they'll also let you know if you overfill :D

Fill till they dribble

Few notes -

You WILL need a gear oil pump to get the gear oil from the bottle to the tranny/diff. I've tried other methods, trust me, you need a pump :). It can be tricky finding a small pump that will fit Redline/Royal Purple bottles. Autozone had one that was for some sort of marine use - had a check valve at the end of the fill tube. Ditch the check valve, you're good to go.

ALWAYS remove the fill plug first. If you end up not being able to get the fill plug off for some weird reason, or you strip it out or something, at least the car still has gear oil in it and can be driven!

Dunno the exact torque specs for the two plugs, but around 30-40 ft-lbs. Just enough to crush and seal the washer. Make sure the washer and the sealing surfaces are clean and free from dirt, too.

BTW, it still weirds me out seeing undercar pics of a NEW Mazda, with everything nice and clean and new. I'm used to 100,000+ mile RX-7's that are filthy and rusty looking underneath! :)

Dale

if you're pumping out the liquid, why does it need to fit any bottle?

cause you can't pour in new fluid sideways.

Credits to jdl :) !!
 

Omicron,
Why yes, that would be our forum member "jdl".

Please edit your original post to include the change tranny oil thread, where in post #10, jdl posted his link that you quoted.

There a ton of other good info in that thread.

BTW, I did not use no stinkin' commercial pump ;) to change my tranny fluid, I used a $5 flotool (clear tubing attached to a valve that fits a 20 oz plastic soda bottle) described in the "change tranny oil" thread.

I funneled the tranny/diff lubes into a cleaned/dried out 20 oz Dr. Pepper bottle, attached the flotool to the 20 oz bottle, put the tube into the appropriate filler hole, tilted the bottle so it was sideways and higher than the filler hole, opened the valve, then squeezed the bottle so it forced lube into the filler hole. It worked really well for me.

Like I said, lots of other good stuff in that thread.

rx8cited

where can i buy this $5 flotool.... and after every 3000 miles should the tranny and differential fluid be replaced??? :D

I bought mine at Advance Auto Parts and I've seen them at Pepboys. There's a link that has a picture of it in my post here. Note that I've seen flotool's valve pictured red here also come in yellow.

Every 3k ? Heck no! The Owner's Manual recommends replacing the manual transmission / differential fluids at 60k/30k miles for normal/severe schedule, so I'd suggest replacing the factory non-synthetic with synthetic Red Line lube around 1500 miles, then again at your normal scheduled service interval per the manual.

rx8cited

PS: Omicron, jdl's been made aware of this DIY.

Thanks rx8cited.... ill go and change my trans fluid and diff fluid this weekend to the synthetic... also... where can i buy the crush washers??? at any harware store or auto store??? sorry so newb.... :p this is my first time changing the fluids for my car :D

I bought the washers from the dealer.

When I bought mine, they had to be ordered, but came within two days.

I've heard of people resuing them also, but is it really worth taking a chance doing that? Not for me. The cost of the lube, my labor, and potential damage caused by leaks is just not worth risking a couple of buck.

Don't rush to do it this weekend if you cannot get all the right parts and don't have the right tools ;).

rx8cited

All updated... thanks!

Also, can anyone tell me where to get those nifty magnetic drain plugs?

I'm not sure what your application is ...... the stock differential and manual transmission plugs have magnets built-in.

rx8cited

They do? Even better, thanks! :D

Cool... i will order for a dealer and just go and buy supplies this weekend.... next weekend, im going to change the oil and the other two fluids. BTW... changing trans and diff oils ... it is as easy as oil changing the rx8.. no??? :rolleyes: :confused:

You tell me next weekend :). I've never changed my motor oil .......... because I have free maintenance for 4 years :D. I have the dealer do it every 5k.

rx8cited

The picture for this post was lost when the forum was upgraded so here is the post again.

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To level the car for installing the MT oil I did the following:

There is a mild incline (15-20 degree) in my parking pad going up to my garage. I did the following:

1. Backed the car into the garage

2. Placed a pair of Rhinoramps down the incline in front of the car so the top if the Rhinoramp was level with the garage floor.

3. Drove the car out of the garage and onto the Rhinoramps resulting in the car with its front wheels on the Rhinoramps and rear wheels in the garage.

It took 4 or 5 tries to position the Rhinoramps at the right spot on the incline so their top was just level with the garage floor. To confirm the car was level, I first used a carpenter's level on the top part of the door sill with all 4 wheels in the garage, then checked to confirm the same reading with 2 wheels on the Rhinoramps.

This results in plenty of room to work on the Tranny from underneath the car. I used this technique when putting RedLine MTL in my Miata (which is even lower to the ground) years ago. Looks pretty goofy though!

You know it's a bitch finding any portion of the RX-8 that is "level" when the car is on level pavement, too many styling lines and curves.

The pictures for this post were also lost, so here they are again.

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With the car raised up, I used an inexpensive pump (first picture) to install the oil in the transmission (second picture). The same pump can then used to move the old oil into the empty bottles (third picture) for recycling.

The pump can be purchased at most auto parts stores. My local NAPA Auto Parts store has two types of these pumps in the $5-$6 range. You will find them in the Gear Oil section.

Ok, silly question, but... (go ahead and laugh if you need to)

If I have a level working surface for my 8, is it necessary or "nice-to" put the car up on blocks to do the tranny & differential oil swaps? I guess I could crawl underneath to confirm, but I'm at work and don't want security to drive up and start asking what the heck I'm doing.

BTW, thanks everyone that has contributed info to this and the other linked threads. This is such a supportive site. I love this place and I love my car... No wonder someone here described it as a cult! :)

-Dennis

Not possible....
 

I would have to say that fluid changes without raising the body a little would not be possible.

An oil change, where you use a shallow pan and an extension socket is do-able, but not tranny or diff.

If you want a really stable, level and safe lift, you should get two ramps, a jack and two jackstands.

Put the ramps behind, and put a little wood between the wheels and the ramp, to give the tires a 'head start'. The rear wheel drive will scoot the wheels up, then leave it in gear, handbrake on.

Ain't going nowhere. Then jack the front at the frame rail just ahead of the motor, jack it way up until it's level, front to back, then lower it gently onto your two jackstands.

Solid as a rock, safe and lots of room to torque stuff......enjoy!

S

Gotta get to Sears!
 

Well, thanks for taking the time to reply, and for the advice on safe lifting.

Looks like my Sears shopping list is going to be a little longer, but hey, can you have too many tools? I didn't think so! :)

Thanks again,
-Dennis

howto update
 

Well, I did a little website maintenance on the transmission and differential oil change howto -- I fixed several outdated links mainly due to Red Line's own website reorganization.

Hope it's still helpful,
-jd.

jdl,

Could you also update on your website the part numbers for the differential fill and drain crush washers? You have both as 9956-41-800 but that is actually the part number for the drain crush washer ONLY (which is silver in appearance). The fill crush washer part number is 9956-21-800 (which is copper in appearance, as your pics show). Thanks.