wassup_nuthin

Ok so im pretty much on my third transmission. 1st tranny synchros were rebuilt around 40k miles 2nd and 3rd. Then that tranny went out 10k miles later it started doing the same, so mazda put a used tranny in my car to replace it. the tranny had about 48k miles on it when put in. As soon as i got the car back i could already feel grinding in 4th and 5th gears. Now i had a new motor and the tranny put in at the same time, so i just got the new motor broken in about a month ago and yesterday i decide to change the transmission fluid, and it was like black water. I add in the new redline oil, and now 4th gear grinds even worse than b4! Now anytime i shift it grinds to where it used to be just at higher rpms and now at high rpms i can barley get it into gear. Why would that be? its not low on oil i dont get it! So ill be taking my car in to mazda now and either they will rebuild this one or maybe finally put a brand new one in it.

Spinning Sushi

iTrader: (21)

What grade tranny fluid are you using?

nycgps

iTrader: (1)

they probably didnt install it right.

Spinning Sushi

iTrader: (21)

You mentioned Redline Transmission Fluid but I'm sure hoping that you didn't use anything besides MT-90 in your transmission.

nycgps

iTrader: (1)

Me, MT-90 in Tranny.

Me, Happy.

wassup_nuthin

actually i thinik it is the ns so should i drain it and put in the mt, or just take it to the dealer and have it fixed?

Spinning Sushi

iTrader: (21)

Yes, NS doesn't have any modifiers that your transmission need. That is the reason why it's grinding so much, I'm guessing that you're using 75w90NS (well, it's bad to use anything that has NS in it), that's a bad thing to do since it's lacking GL5 along with other modifiers.

It is HIGHLY recommended for you to change it out and use Redline MT-90 instead before you destroy your synchros and gears.

kersh4w

iTrader: (3)

stop drag racing so much. :P

nycgps

iTrader: (1)

err...

the NS means its a GL-5 fluid but without the fiction modifier for LSD.

so it could be use on tranny but I prefer GL4 over GL5 for transmission anyday. use MT-90.

Psychofox

could it be broken clutch pedal bracket?

mysql

You want GL4. My first transmission died after prolonged use of GL5 maxgear.

wassup_nuthin

No its not the clutch. its only 4th and 5th gear. other gears shift wonderfully. I havnt even been racing it sinc i just got a new motor put in and just broken it in! So i should switch it to mt90? or should i just go ahead and take it to the dealer? either way it seems the synchros are startin to go.

nycgps

iTrader: (1)

take it to the dealer first, since there is no way they can tell what kind of fluid u have in there. Actually when they try to drain it they will probably skip the "Have you did any maintenance to your transmission fluid?" as its gonna look really new.

bose

iTrader: (5)

So you want MT-90 in the tranny. what goes in the diff? Same thing or the 75w90ns?

nycgps

iTrader: (1)

...

MT-90 in tranny,
http://www.redlineoil.com/products_g...7&categoryID=7


For rear Diff, do NOT use 75w90ns. Use the regular 75w90.
http://www.redlineoil.com/products_g...5&categoryID=6

bose

iTrader: (5)

Thanks for the info nycgps.