ok guys im confused. Imma take it in for them to change both the tranny and differential oil. What r most people buyin and how much of it do i buy. And where would be nice too. Jus give me a shoppin list for supplies i can just give to the mechanic. Thanks

Royal Purple Max Gear fluid for both tranny and differential. Royal Purple 5w20 engine oil.
Royal Purple coolant additive (or Redline water wetter).

When I used the MaxGear in the tranny I found the fluid to be very difficult to flow in cooler temps, like 50 degrees or less, and I switched to SynchroMax. I discovered that the MaxGear was so hard to flow that it put three tenths back on my e.t. The SynchroMax put me back to where I was. However, the MaxGear seemed to cushion the shock better. I am more comfortable using the Synchro in the trans.

CRH

hmmm I brought SynchroMax before too and I brought it in for my dealer to change it while I was brining the 8 for a service. He took a look at the stuff and he refused to put it in saying it was too thin and would void my warrenty if I used it??? but yea I emailed Royal Purple and they said I should use Max Gear but then the weight is the same for Synchromax so I really don't know anymore lol

The thing I found with the MaxGear was that at cooler temps the idle rpm would drop dramatically when I let the clutch pedal out. The factory stuff and the Synchro seem to behave in similar fashion to one another with regard to idle speeds and cool temps. I don't place too much weight on the opinions of mechanics at the dealer unless I have spent considerable time talking to them, individually. I was well on my way to becoming a mechanic, myself, so I know how the game works. These days the schools teach them how to read codes and swap parts. Critical thinking and analysis? Understanding the physics that makes machines work? Forget it.

How's this for a Summer project; I will be modifying my factory tranny to make it stronger, shift quicker, and run quieter.

CRH

Considering i have only found this thread i hope i have made the right choice ;)
I am getting Royal Purple oil for my differential and my transmission apparently it works better than Redline oil , the only downside is they want you to buy it bulk here in Australia 12 liters at a time :eek: , but i managed to get a 6 litre pack to try out at cost :cool: .

From memory 1.7 litres for the diff and 1.3 for the transmission, the rest i will store for next time .

cheers
michael

im a littttlllle confused. So do i use maxgear for both the tranny and the diff. Or do i use synchromax

I will use Maxgear since that's the response I got from Royal Purple themseleves when I emailed them about usage on a RX8
just make sure you get the correct weight oil (look in your manual)

we use 75w90 right, thanks alot guys

sweet, what are you going to do exactly to your tranny? or is it a secret..is its a secret whisper it in my ear:D

I started a "transmission mods" thread so we should probably take the discussion over there....

CRH

I just replaced mine this weekend with Redline products MT-90 (2 bottle bought) in the trans and 75-90 (2 bottle bought) in the rear at 16,000 miles and the stuff that came out was pretty burnt up no way it would have been good in there till 60k. The feel is much better and I am sure that the parts will thank me for it later.