Difficulty shifting 6MT Please help!
 

Hey everyone,

Lately Ive been finding myself having to use extra force to get the car into the next desired gear, Almost like the car doesn't wont to go into the next gear. This typically happens when shifting from 1st to 2nd but occasionally shifting from 2nd to 3rd and 5th to 6th as well. This problem is much more pronounced when the fluids are still cold and not up to operating temperature, and if it matters the gear box is filled with Motul synthetic atm.

Ive been searching through the forum a bit and apparently the syncros aren't the strongest but, while shifting requires some added attention/effort I'm not
crunching gears or grinding them either. I do however get the usual clunk when shifting from 1st to 2nd if i don't get the shift down just right, which is common and considered a normal characteristic for the 6mt. Now Ive also read that the csc is another apparent weak link in the z, and was wondering if this could be the problem? The pedal isn't mushy but my fluid doesn't look all that great, could there be a fault with it?

Picture of the clutch fluid condition below.

which Motul oil do you have in the box at the moment?
gearbox takes GL4 oil only.
diff takes GL5 only.

using GL5 in your box will destroy the syncros and make shifting difficult.

your clutch fluid looks like mine before the level kept dropping. keep an eye on it

I would rule out bad syncros. Usually you'll have one gear that is really hard to get into, but not all of them like you are experiencing. I would say that your csc or cmc is going bad. Sounds like the hydraulic system isn't building up enough pressure in order for the csc to be able to push in all the way on the pressure plate to disengage the disk.

* I would take care of the easy stuff. Bleed/flush your clutch fluid, and change the transmission fluid.

Yeah I'm pretty sure it's not gl5, the previous owner changed all fluids to motul and I'm pretty sure it's 75w90 gear lube.

As for the clutch fluid, it looks like the rubber that seals the csc might be deteriorating which is causing the fluid to change color. At least that's my take on it, everyone seems to think the color change is normal though.

Exactly what I was thinking, I'm really really hoping it's nothing internally wrong with the transmission!

I have some Motul rbf 600 that I plan on using when I flush the clutch fluid, I just need to find someone to help me do it or pay someone to do it for me.

As for the transmission, do you think I should go back to the Nissan stuff or keep it motul?

That fluid doesn't look too bad. It can go longer. The most common mistake would be someone put in 80w90 in the tranny. This will cause horrible shifting when the tranny is cold. It will be very stiff as you describe in colder weather.

I forgot to add that I have been sucking out the dirty fluid from the reservoir and topping it off with fresh fluid. I haven't actually flushed it out yet though, and last time I cleaned it out the fluid was pretty much black.

As for using the wrong weight fluid, I dont think that's the problem. Although I wish it was as simple as that!

What DOT fluid have you been using? DOT 4 changes to that brownish burnt color extremely fast.

And I agree about the wrong weight fluid not causing the problem. But it wouldn't hurt to change out it and see what happens. Remember, the manual tranny uses 75w-85, and make sure its a GL-4 gear oil. Flush the hydraulic system with some fresh brake fluid and go from there.

I'm currently using valvoline synthetic dot 3 & 4 brake fluid, but I have a unopened bottle of motul rbf600 that I'll be using when the system is eventually flushed out.

And while the color changing is considered normal, if you look at the picture I posted there seems to be some really fine black particles sitting at the bottle of the reservoir which dont seem to be normal.

So yeah I'll definitely be changing the fluids ASAP since it's the cheapest option and go from there, I'll keep everyone posted!

If anyone else has any Input please feel free to share!

Sounds like CSC is fixing to fail !

that does look like a bunch of metal particles in that fluid.
You're CQC or CMC is done.:shakes head:

That's what I'm starting to think too!

While I definitely think there is something up with the hydraulic system, the little particles in the reservoir are not metal. Last time I sucked up the dirty fluid from the reservoir there were little particles as well, and they just kind of mixed in with the fluid once I agitated it. :confused:

Its dirt/debris and clutch dust that makes it past the csc seal. Common problem.

I dont know what to say to u guys ive never seen those particles that big in my fluid, dont get me wrong i have personally bleeded my clutch twice and i only had particles coming out no bigger than sand grain size, those seems to be rubber cuts or something.

Just my two cents.