Don't use any Redline products with NS in the description. They lack modifiers.

 

RP max gear for me, so sar i feel better shifts, i don't double clutch the reverse any more, and feels real smooth... no grinding to report here...

BTW RP 5-20 in the engine too... no problems noted

 

I used to use RP for 38K miles. then my tranny starts having this *BOV* kind of noise when I clutch going faster than 30 mph.

Switched to Redline MT-90, noise disappeared after a week.

Im going to switch my rear diff to Redline's stuff later. Now its still using MaxGear.

 

lol. That's what we all reported the first few years. Then the car magically needs a new transmission.

 

Unfortunately I cannot just magically turn back the odometer miles. There are strong recommendations for Royal Purple Max Gear peppered all over rx8club, and if they are all wrong, everything I know is jeopardized.

Perhaps even Redline MT-90 is not without its share of problems. Maybe in another few years it will eat through the transmission covers.

It's possible as well that the suspicious noises went away simply due to fresh fluid, not from switching one brand to another.

We suspect, but cannot prove.

Maybe in a few years we'll report that pre-mix or any other rotarded behavior has unintended consequences on rx8.

 

Royal Purple Max Gear have been proven that it's not good for our transmissions. They lack special additives and modifiers that our transmission require. Hey, it's your transmission though, not mine. Feel free to use it.

 

Mobile 1 works.

 

Where exactly is the concrete proof? I see a lot of anecdotal evidence and some conjecture due to its ratings, but nothing that would qualify as scientific proof that the Royal Purple is bad for your transmission.

(Note, this doesn't mean the Royal Purple might not be bad, but I haven't seen what could constitute as proof.)

 

ran rp maxgear for 55k trouble free miles.. am going to b&g soon..

beers

 

I swapped transmission fluid once a year. Because maxgear was better feeling during cold starts, I kept it over redline. The last two fluid changes things were feeling rougher. With the most serious grinding issues taking place almost immediately after the last fluid swap. In fact, I did the last fluid swap ahead of schedule because the transmission was feeling notchy and crappy and I hoped new fluid would smoothen it out.

I do not need more proof than this. I ran maxgear for over 40k miles, half of which was turbocharged.

 

Exactly. I think individual driving habits and our usage of the clutch pedal is by far the factor in transmission swaps. Seems a little pointless to blame RP for failed transmissions, when race teams have already commented time and time again to the weakness of the stock tranny under aggressive driving conditions.

How can you blame RP for failure, when you operated your car well outside of the parameters of the factory RX-8 with the turbo? Seems skewed from the information you've supplied.

 

The grinding started before the turbo was installed. It got worse as time went on. I do not drop the clutch or do anything funky with the transmission.

I don't care if anyone believes me, I'm just throwing in my 2 cents. I joined the crowd who swapped around fluids 4 years back and maxgear felt the best to me at the time. Initially it feels good for everyone, that's why so many used it.

 

It has nothing to do with believing you or not. You didn't state whether the issues began pre or post turbo so I was seeking clarification.

I'm actually thinking I'll switch to redline or some other at my next gear change simply to see if there is a difference. I've always used RP and my transmission has been fine. But I also can't say that it is smoother/better with it than with any other gear oil out there...

 

extra hot non-fat mocha with 2 extra shots of espresso

oh, and only clueless twits think there's anything wrong with GL-5 oil

 

don't listen to the book experts that have no direct experience, it's a perfect choice for your transmission.

 

The NS is actually what you want, the regular has modifiers for LS diffs and these can cause the synchros to have a harder time speeding/slowing. I used RP affter using Redline MT90 and within 5000 miles I had a constant 2nd gear grinding. Went back to MT90 and it was gone after 20 minutes of driving. You decide...

When I change again, I am going with a 75-90ns or 75-140ns Redline.

 

Or just go for GL-4 Fluid

 

I changed out the stock fluid with Redline MT90 and 75W90 gear oil, it feels much better so far.

 

It is a challenge to keep up with the latest rx8club fads. It's almost a "rumor of the week" on what is "in" as far as "protecting" the rotary engine.

There should be a gauge on the club homepage that points to what weight of engine oil is currently in fashion, based on the number of positive comments for that specific weight type within the last 14 days.

All this conjecture is the only thing I have to base rx8 decisions off of. Yesterday I emptied transmission of MaxGear and pumped in the Redline MT90 just to silence the nagging psychological rumors.

It's all psychological but I can't stop myself from performing all these things. I'm not hurting anything, just spending money on ordering more washers from the Mazda parts counter, and spending some hours getting dirty.

 

on the same boat here buddy, and my ride is pretty new. any real THIN synthetic fluid that i used (RP) problems would start. i got the whole cold morning notchy shifting deal with it.

unfortunately... its hard as hell to find a GL-4 trans specific fluid. so i ran with some valvoline thicker gear oil with some left over RP in there. and put in a **** load of lucas oil stabilizer...

now being more careful with fluids, those GL-5 stuff doesn't perform well in the trans as it was meant to be in the diff with diff additive.

so yeah, i'd like to just find some thick conventional name brand GL-4 fluid for the trans if not able to find what they use for oem.

*note* new owners, don't even bother with the experiment! i've confirmed with other mazda owners/techs/roadster club members, the GL-5 specs fluids gives worst shift quality, new or old. whereas switching out with GL-4 spec rather name brand or not (like mag1 or some other CRC product) will not give any worst shift quality. or the thicker viscosity it is, the shift problems doesnt show up for some reason... even being a GL-5 spec fluid.

this is my experience and opinion... i find it useless to try the synthetics.
but the diff is another story.

 

user 24, we all like to help others to be more informed. but learning out for ourselfs is also something we all need to do before spreading rumors.

i thought this has been covered before, but i guess i'll cover it again.

there are NO added benefits with using RP for the trans. its a hybrid GL4/GL5 fluid, and will create cold fluid issues such as notchyness and possible shift grind before warm-up.

racing beats pride and recommendation of RP fluids may be different than our intended use as their car may always see extreme high temps and pressure during vehicle operation time. hence the reason why on my brand spanking new car and trans with RP fluids... is more notchy and has a higher tendency to want to grind during the cold morning temps anywhere under 60degrees.

i use to get these fluid specs mixed up myself as having to own 2-3 other RWD's w/o a lsd. i'd simply just get any ol GL4 gear oil that was cheap and available...
but NO, not the rx-8. its got a nice LSD and a premium trans with all the works, but is very sensitive.

so i guess my point is, choose wisely. and don't simply follow someone's recommendation of what they "think" is good. but try to learn the grades/ratings/ and match oem specs before doing anything, and you'll be clear of ANY problems.

we're all human. mistakes happens to even the best of us!
good luck on ur fluid choice.

TM

 

i want to change my gear box oil..
buti don't know..
where to buy it...
i leave in malaysia....
and how much?

 

I've tried Royal Purple MaxGear and Redline MT-90 in my tranny and the Redline shifts noticeably smoother than RP and the cold grinds go away really quick. So I recommend Redline over RP, at least in my NE climate.

As far as the diff goes, it seems fine, there's nothing weird/wrong with the rear diff, so I have no idea how to tell the difference vs stock vs RP vs Redline fluids.

 

I use Greddy Trust gear oil 75w90 GL6.
It's just perfect. Much smoother than the oem stuff and get's even better when warmed up.
What I would like to test though is Lubrication Engineers' Gear Oil, which I believe must be better than anything else.
P.S. I have a low power 5MT (EUDM) which I think has a gearbox from the older MX5 Miata. Gear-switching with this gearbox has always been very hard, so the difference with the Trust gear oil was very noticeable.

 

1 1/2 month later after switch from RP to RL, this is what I got.

Used to have RP Max Gear in transmission early on, within first few months. Then, ordered on-line MT90 and put into transmission when I considered these comments here. Now, the transmission has the famous noise when the clutch is out.

Seriously, the noise sounds like a pathetic robot. Like a kid's science project robot that has just run out of batteries and can't get back up over and over again. It's terrible!

So would you rather do RP MaxGear and have a smooth sounding transmission, or switch to MT90 and get some grinding noises, and surprisingly according to some theory it is MT90 that is supposed to be better for your transmission?

Now, the third option needs to gain some more momentum. 50/50 mixx RP/RL. That's going to be the new trend. You read it right here on rx8clubz. Several offshoots will be 75/25 mixx RP to RL, or 60/30 mixx RL to RP. Always topping off with 2% rotary magik, 4% rumors.