when I used redline, I did same as you - two different types. With RP there is no need for that.

so you used

4 quarts of Synchromax Manual Transmission Fluid (831-01512)

or

4 quarts of Max-Gear Oil 75W-90 (831-01300)???

i actually ordered 2 of each...

how is it that for RP you don't need to use two different types?

Trans & Diff changie w/out jacking car
 

Is it impossible or just a huge pain in the ass to do this with the car on the ground. I'm 6'5 and have very long arms.

Anything is possible I guess, but I doubt seriously if you can do that. Get some jack stands--they're not too expensive-- and raise the entire car. Keep it level. And even then, this task can be a royal PITA with slippery, smelly gear lube everywhere if you're not careful.

You might be able to unscrew the plug, but you will never be able to fill it. If this is the only thing you will ever need jackstands for, then I'd take it to someone with a lift. I paid $60 for labor when I did it. I woulda bought jackstands but I would have NEVER used them again after that.

It's easy to do the diff with the car on the ground. You can reach under the car no problem, all you need is a fluid pump.

If you take out the shifter, you can pour fluid in the transmission from the top. In this case, all you need to do is pull the drain plug and fill plug, which you can do with just the jack that comes with the car since you don't really end up under the car.

Anyway, I did change both fluids without getting physically under the car very much, and I have a full set of jacks and jack stands. This was just easier.

Thanks to all who posted great advice. I changed both trans and diff with Red Line this afternoon and it wasn't much of a job at all. Thanks for the idea of using ramps on a slanted driveway, this is a very easy way to get your car in the air and level.

The only thing I have to add is some advice on getting the fluid in. I went with the Flotool and purchased 10 feet of tubing from Menards for 2 bucks. I would put one end of the tube in the fill hole and then just custom cut it for both the diff and trans. For the diff, I found it easiest to thread the hose just behind the rear tire. It's a strait shot to the fill plug. I set a small ladder next to my car and used a twisty tie to hold the funnel up in the air.

I heated my fluid before pouring. This makes a HUGE difference, as i got it pretty hot so it was like pouring water down a funnel. I just put the bottles in a cooler, stood it on end, and set a space heater in front of it for a half hour or so.

Thanks to all for providing advice that made this pretty easy for me.

how many quarts
 

how many quarts would i need to replace the tranny & diff oils? would a gallon be enough for both?
:nono: yes i'm lazy!

Less than 2 quarts for each. A gallon would be plenty, but most people run different oils in the tranny and diff, so they don't buy one gallon.

what do u guys think?
 

SPECIALTY FORMULATIONS
their products are supposed to be great... i've heard lots of good feedback...
this is their MT Fluid
and this is their Diff Lube
anybody used their products before???

can someone please tell me the best online store to get some redline or royal purple fluids? nobody stocks the stuff locally around here....

Rosenthal Mazda and Trussville Mazda both have Redline oil. See the Vendor section of the forum. OGRacing.com has it as well.

Finally was able to do this on my tranny, skipped doing it in the differential because the dealer had just put something in there when I last took it there. I used Royal Purple Max-Gear Oil 75W-90 since Racing Beat had it when I visited them. But there's something odd... the car's so quiet now. :) I'm just not used to that.

Thank you so much for the DIY and getting me off my ass to do this.

Just did this today... it's amazing. My transmission is SO quiet now!! The car is quieter from the outside by a lot, acceleration seems smoother, and first to second actually happen at high rpms instead of grinding! If you have $40 to buy the fluid, do this DIY. You won't regret it.

How long ago did you do this? Any issues? Anyone else running RP Max-Gear 75W-90 in both the MT and rear diff who can comment?

I have a local NAPA that carries royal purple. They have the Max gear in 75-90 and 75-140, but were either out or do not carry the Synchromax. In the Owner's manual, it specifies 75W-90 GL-5 for the MT, so the same fluid should work for both safely. I am just wondering whether the Max-Gear would feel as good as the synchromax.

Since I am changing it myself, I guess it's only a $14 mistake if I don't like it. :)

BTW: Napa had RP at $6.99 per bottle (for gear oil and 5W20!!!), which seems to be less than some people have paid. If you have a Napa nearby, check into it.

Just found this info at RPMOil.com

"Synchromax® is recommended for manual transmissions that specify an automatic transmission fluid or motor oil."

Wow. I guess I'll avoid this and stay with the Max-Gear 75W-90.

Look here for Royal Purple's recommendation:

http://www.royalpurple.com/techa/tranxref.html

They do not list specifics for Mazda, but in general, Manual trannys that require a GL-4 or GL-5 75W-90 should use the Max Gear 75W-90. That's what I'll do, and I'll post my impressions.

Yeah, Max-Gear worked fine for me. :)

I hate f'ing dealerships!!!!!!!!!

Trying to switch over to RP. Got car all jacked up and on jackstands, and it turns out I don't have a large enough metric socket. Tried a 15/16, which should have gotten them off HAD THEY BEEN TORQUED TO SPEC. Could not even budge them with a cheater bar or by hammering on the end of my socket wrench. Gotta wait now till the wife gets home, so I can make a trip to Lowes.

Some real good information in this thread on how to change oil in Manual/Standard shift RX8's, but does anyone have advice on how to change the Transmission fluid in the Automatic RX8

Did this today. Switched to Royal Purple. 4500 miles on the odometer. For those wondering, I ordered 4 quarts and ended up with a little left over. I was tempted at first to order 5 quarts just in case but it was so expensive I took a chance with just 4 and it paid off. Put the car on jackstands and found the drain and fill plugs easy to remove. There was definately some buildup on the magnetic plugs so I was glad to get that stuff out of there. . Thanks to this forum, I had the right tools including the 23 and 24 mm sockets and torque wrench. I used the marine type pump for $10 that fit the 1 quart bottle perfectly. Got everything I needed at Pep Boys. To be honest, I can't tell much diference yet but I'm still glad I did it and I think it will pay off in the long run with less wear, ect. Thanks goes to everyone who posted useful info for this DIY!

I just did mine... very noticeable difference. I no longer feel the transmission shifting when I go from 1st to 2nd. All the other gears feel more or less the same... time for a short shifter now!

If you fill fluid in from the shifter hole, is there any way to add TOO much fluid? I was just kinda curious as to how to gauge it.

The way to gauge it is by doing the job right. Fill up the case till the fluid comes out the top hole. Why on earth would you take the time to remove the shifter to fill the trans when Mazda gives you a fill hole behind one bolt?

Well I originally did the job the way that Mazda intended it, with the fill hole. However, my tranny was still pretty noisy. So when I installed my AFE short shifter, I decided to add a little redline from that hole. The difference was immediate. The tranmission noise went away completely.

I just wonder if maybe Mazda put that fill hole a little lower than they should have? It would certainly explain the excessive gear noise that comes with the car stock.