Has anyone switched from the factory manual trans fluid (oil) to another synthetic brand, and what weight? Anything better to quiet the 'normal' noise? I've heard even the factory fluid is already synthetic.

 

good question no one has any input?

 

I heard that using GM's synchromesh fluid worked pretty well

 

^ X100

i went to that on my sentra ser's 6speed. The trannies in those cars were having notchiness issues. it cleaned it up to almost being unnoticeable.



i am gonna start a new thread after this one dies down asking if anyone swithced their auto tranny fluid and rear diff fluid to synthetic.

 

bump...

Anyone changed out their 6MT fluid?
Amsoil, Royal P. etc

 

also interested to know... however i heard that using any other fluid than the OEM will void the tranny warranty... true?

 

^ yes for the AT.
I didn't think that was the case for the 6MT though.

 

iv heard its for both and while talking to a local nissan mechanic he said to stay away fromm the GM syncromesh cause it does allow the tranny to beocme quieter but does not protect as well as the OEM fluid and when you take it in for warranty work, thats their way out...
just a heads up, when i get my fluid changed i will pay the extar dinero and take it to the dealer to fill in with fluid of my choice as ling as they have no objections...

 

I just checked the owners manual...
2nd Gen is same as 1st.
It's the AT that has the warranty warning if you use something other than J-Matic.
There is no such warning for the 6MT

 

i had good luck with the penzoil synchromesh product in my old 240 tranny. but that was after 150K miles - long out of warranty.

it quieted it down and make it shift a lot smoother.

i think the protection issue has something to do with brass components in the trans. can't really remember what i've read but it may be that the synchromesh formula doesn't protect brass parts from wear or corrosion and thus can shorten the life of a tranny with these parts in it? not sure, and not sure if there is any brass in our transmissions.

i realize that may not be much help but might jog someone else's memory or get you started on an internet search.....

amp

 

Synchromesh is not very thick and cannot stand up to the abuse of aggressive driving. Expect to get much less life out of the fluid as opposed to OEM fluid.

I used synchromesh in one of my WRX's to combat a 4th gear grind and it went away but gear noise was increased. When I drained the fluid after around 10k miles later, it was as thin as ATF and concerned me greatly.

My next car was an STI and I wasn't going to risk its transmission and so I used 100% redline shockproof lightweight which is really diff fluid. Amazingly, though, my gears shifted as smooth as butter. The center differential was noticeably grabbier though so the friction properties were higher and I had some problems with front to rear diff lockup on slow tight turns so I don't know I'd recommend that either.

In the subaru world, the flavor of choice is actually a mixture of shockproof lightweight, synchromesh, and MT90. People used to swear by it...but I haven't snooped around that world for about 3 years now so longterm, I don't know the outcome.

 

So has anyone tried anything yet?

I think I'll start off by trying Amsoil on my 6MT and will probably do it this weekend.

 

Let us know the results!!!

 

Redline X90

 

I know some people who use this