"For the rear differential drain plug: a 24mm socket fits loose, 22mm does not fit, 23mm fits the best, and 23mm deep won't fit"

Was the 15/16 loose on the diff drain plug?

 

No, it fit perfectly. Also, the plugs are not 'tight', so getting them off was easy.

 

This one was from Pep Boys. It's a simple affair. As mentioned, gear oil flows at a leisurely rate unless it's heated. So using the pump dry (new) it can take a while before oil actually is drawn into the cylinder. Just takes a bit of patience. Then you have a good seal and it pumps easily enough.

Depending on what fluids you intend to use you may want to get 2 pumps to avoid putting any of the wrong stuff in the wrong box (what is it again - no GL4 in the diff?). Or is separate pumps just ****? I haven't switched fluids in the 8 yet.

 

I bought the same pump, but did not even bother opening it because my on/off fluid tool with squeezable Dr. Pepper bottle method worked so well - no lube heating required.

I did not want to deal with cleaning the thick lube out of the pump and its "miles" of tubing.

rx8cited

 

me again hopefully last question :D

do you need two crush washers for the tranny and two for the differential. Have RX-8 washers become available?

Do you really need to replace them each time?

 

My 2 cents worth ..... I spend $30k+ on the car ..... I was not about to try and save a few bucks reusing the available washers which the service manual says to replace. My dealer had to order two of the four washers and had them within 2 days.

The hassle of the rework required if I reused the washers and they leaked was not worth risking.

rx8cited

 

I ordered all of them from my dealer, and had them in 2 days

 

just ordered some washer myself, and the guy said the ones for the differential were the same ones that go with the oil tank...said he'd give me a handful of those for free...had to order the ones for the tranny though...

 

No good deed goes un-punished ....

After reading this thread, and having a Mazda $50 gift certificate, I decided to have the transmission oil and differential oil changed at my 8 month service (only 6K miles but I am on maint schedule 2).

Big mistake! What was a beautifully smooth shifting transmission has become very rough. The synchronizers are noticeably "sticky" going into any gear where the engine/drivetriain speeds don't match perfectly. The shifter has taken on a very "notchey" feel. I don't know what brand "goo" they used to make such a noticeable difference but apparently the RX-8 transmission isn't very forgiving.

So I have to do penance, buy the MT 90 and install it myself. I used Red Line in my Miata and loved it so I hope the MT 90 will give me back the wonderful transmission that came with my car.

 

I had exactly the same experience. Especially 1-2 upshift.

Ordered the MT-90; should be in the car by the end of next week.

Good Luck!

 

msrecant and NEWireless,
Sorry to hear of your misfortunes with the mystery transmission oil and differential lubes that the dealers used . I'd bet that they're not using synthetics and specifically the Red Line products we touted on this thread.

I'd hope they used the equivalent of what the Mazda factory used so I wonder why the shifting got messed up so badly?

Hope to hear that your shifting is all better after you put the Red Line MT-90 in.

 

Yeah, I was real suprised. I wasn't expecting performance like the Red Line product, but I didn't expect it to perform worse.

I couldn't believe that the dealer would (or could) use an MT oil that would be so noticeably different from the factory MT oil. However, it was so different that it only took about 15 minutes of driving to absolutely convince myself that something had changed (for the worse). I even tried to force myself to believe that I was imagining the change, but the stiffness/stickyness doing shifts convinced me otherwise.

Apparently either the transmission is very sensitive to the type of MT oil or there is a real big difference between the factory MT oil and the domestic brands used by US dealerships.

Either way, I'm sure the MT-90, which is currently on order, will fix it.

 

Have you notified the service department of your negative experiences? Hopefully they'd investigate and correct the situation (poor or incorrect lubes I presume) that caused your rough shifting in order to not upset future customers with whatever they did to your transmission.

 

I been debating doing that. Since the MT/Diff oil changes were a freebee I am more dissappointed than angry. Yes, one would hope that they would care about a problem like this. However, based on past experience with this dealership I don't have much hope. They just don't maintain cars with an eye to this level of detail.

If the regular-maintenance wasn't free (I was a pre-order) I would probably be having it done elsewhere.

 

Looking on the bright side, your experience is just a thorough oil change before you do it right yourself. The dealer's replacement oil will do a decent job of clearing out more of the junk you don't want in there for the really long haul anyway
-jd.

 

Got the Red-Line MT-90 in the tranny today for free (thank you 128 Mazda).

Transmission is smooth and easy (as I had originally hoped for).

 

Is it better than before the Dealership MT oil change?

 

Yes, it's noticeably better.

I had no problems before the 1st change, but now the shifting is much smoother.

 

I am impressed! It was pretty smooth before. I should receive my MT-90 sometime this week. I know what I am doing next weekend.

 

I put the MT-90 in yesterday. BIG DIFFERENCE! All shifting problems are gone. I would say it is smoother than the way the RX-8 came, and that was pretty smooth. What ever they put in definitely caused the problem.

The only odd thing was when I first opened the filler port on the MT about 2-3 ounces immediately came out. I went to particular lengths to insure the car was level before starting the process and, after draining, it took the full 1.8 Quarts before it started coming out again. Hence I believe they somehow managed to over-fill the transmission. Don't know if that contributed to the harsh shifting.

 

So how did you get it level? Did you use four jack stands at the jacking locations in the manual?

 

Nothing that easy .....

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 (I will post a picture).

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.

 

I am looking into doing a diff and tranny lube swap to MT-90 and 75W90 over the next few weeks and I was wondering what Mazdas opinion is on this wonderful sounding stuff from redline? Does it screw your warantee on your car in any way, shape, or form?

 

The RedLine products meet the exact specifications in the owner's manual. Also, Mazda does NOT claim that synthetics should be avoided.

Can't see how this would effect warranty.

 

Thanks, great idea. I have a sloped driveway and will give this a try.