Transmission clunky when getting in 3rd gear

[frankronne]

For a couple of months I've been experiencing a clunk (like it's hitting something) especially when shifting from 2nd to 3rd gear. This started when I changed trans oil for Redline Mt-90. At first, it didn't do it when downshifting but it's doing it. It's now doing from time to time when going in 2nd.

And yes, I lubed the linkage under the hood.

Any idea what could it be ? Very strange that Mt-90 worsened my shifting feeling.

Thanks.

[bronsin]

Try bleeding the clutch. If air gets in there it won't shift properly.

[frankronne]

Try bleeding the clutch. If air gets in there it won't shift properly.

You think that could solve the problem ? Thats how you diagnose this clunk? (just in 3rd gear as I said, 4th is smooth as hell). My engagement point is nowhere near the floor.

And how you do it ?

[bronsin]

Get a friend and have them hold the clutch pedal to the floor. You loosen the bleeder bolt and tighten it after the fluid stops. Then tell friend to let the pedal up. If nothing but fluid comes out it's not the clutch. If there's air or it splutters, repeat until you get a solid stream of fluid. You found the problem.

[CoryM]

For a couple of months I've been experiencing a clunk (like it's hitting something) especially when shifting from 2nd to 3rd gear. This started when I changed trans oil for Redline Mt-90. At first, it didn't do it when downshifting but it's doing it. It's now doing from time to time when going in 2nd.

And yes, I lubed the linkage under the hood.

Any idea what could it be ? Very strange that Mt-90 worsened my shifting feeling.

Thanks.

The clunk is caused by the synthetic mt-90 oil. It causes the Syncronizers to not work as well so you are feeling that. Syncronizers are little brakes that slow down the gears so you can shift. They use friction to do this and using more slippery fluid causes them to slip too much. Drain the oil out and put the recommended 75w90 GL5 in and you will be fine. This goes for almost any M/T.

It can be a sign that your Syncros are a bit worn as well, but step one is to get the correct fluid in there.

Cheers.

[tmontague]

I have ran mt-90 in my yaris for the past 3 years for better cold weather shifting. Hasn't caused me any clumps other than the odd reverse shift grind which happened much more previously.

Not discounting what CoryM said as that is true but just shedding light on the other side of it.

Wouldn't hurt to go back to stick fluid and compare shift feel

[Bluevitz-rs]

GL4 is what you want. I've experienced the same issues with GL5 fluids. I've used Amsoil, Castrol and cheap Motomaster 75-90 synthetic fluids. I'm now using Royal Purple 75-90 GL4 full synthetic. It fixed all rough shifting problems I've had over the year of using other fluids.

[frankronne]

GL4 is what you want. I've experienced the same issues with GL5 fluids. I've used Amsoil, Castrol and cheap Motomaster 75-90 synthetic fluids. I'm now using Royal Purple 75-90 GL4 full synthetic. It fixed all rough shifting problems I've had over the year of using other fluids.

Redline Mt-90 is a 75W90 GL4 fluid. I've heard nothing but good reviews about it and now it gives me problems haha. I will probably try getting back to mineral fluid but I dont want to waste 50$ worth of Mt-90...

[Bluevitz-rs]

That's strange. How long did you go with the old oil before changing it out?

[CoryM]

Redline Mt-90 is a 75W90 GL4 fluid. I've heard nothing but good reviews about it and now it hiver me problems haha. I will probably try getting back to mineral fluid but I dont want to waste 50$ worth of Mt-90...

Yeah I know. I did the same thing after people saying were happy with it on this forum and that it improved the shifts. The thing is, I should know better. I'd already run in to the same issue in my old Camaro.

After going back to regular oil, shifts were as good as before. Syncros are happy and working well.

Cheers.

[dogsridewith]

What is your "regular" manual transmission oil?

[frankronne]

That's strange. How long did you go with the old oil before changing it out?

I changed the fluid to Redline Mt-90 at 70000 kms and now I'm at 77000 kms and the odd feeling in 3rd gear gets worse and worse. Before changing to Redline it wasn't even there.

I complained at my dealer about it. They went with me on a test drive (with me driving, saying that I know the feeling and not them). I explained my problem to the mechanic and he was like it's normal, when he didn't even try it...

[CoryM]

What is your "regular" manual transmission oil?

Non-synthetic 75w90. Toyota says GL5 or GL4 is fine, but GL4 is probably the better bet (less slippery). I don't remember what brand I used but likely Quaker State. Interestingly I called a Toyota dealer to buy some OE fluid and they said they just use bulk 80w90...... :rolleyes: .

Let's be very clear: The Yaris gearbox is always going to be a little clunky/noisy. It's just not a very smooth box. It is, however, a very durable unit and works fine for the application with the correct oil. This is one of those cases where you should listen to the engineers. The only reason to consider different M/T oil is really if you are regularly operating outside of the temperature range they designed the car for. And yes, some of you are probably at the far end of that range in Winter. Yuck.

Cheers.

[tmontague]

^well said