Nissan 370Z Forum - View Single Post - Transmission Fluid Issue? Amsoil 80W90. Gears won't engage, shifter heavy when cold?

AlphaSnacks · 01-04-2013, 10:29 PM

I had Amsoil 80W90 filled in my transmission a few weeks ago. I've driven the Z twice since then. And both times the transmission has acted the same way when cold: hard to engage 1st and 2nd when cold and shifter feels heavy (like churning thick butter when wiggled side-to-side).

Before with the OEM fluid, wiggling the shifter was always the same, hot or cold. Now, even when the car is off, you can feel a bit of weight in it, until the transmission warms up and it feels normal.

Engaging 1st and 2nd when cold requires to really push the shifter in. Never had this problem before with OEM. OEM fluid 1st was a bit notchy, but not enough for me to complain about - it never bothered me before. Today, after about 1.5 miles of local driving, at around 1-2MPH I tried to engage 1st, and it just didn't want to engage. It felt like it locked me out of the gear, so I tried to push and I felt a vibration in the knob and I heard a noise very briefly (my music was on, but it sounded like a quick grind).

I immediately stopped trying to force it in, put it back in neutral and tried again, and the gear went in just fine. The grind couldn't have been more than a millisecond, but still, it pissed me off. I've never grinded a gear before.

So is it the transmission fluid? Once it warms up, it's perfectly fine. And stays perfectly fine even after the car's been off for 4-5 hours. Is the fluid no good for our cars? Could it be a bit low?

01-04-2013, 10:29 PM	#1 (permalink)
AlphaSnacks A True Z Fanatic Join Date: Jan 2010 Location: Windermere, FL Posts: 1,618 Drives: '13 XKR-S, '10 370Z Rep Power: 18	Transmission Fluid Issue? Amsoil 80W90. Gears won't engage, shifter heavy when cold? I had Amsoil 80W90 filled in my transmission a few weeks ago. I've driven the Z twice since then. And both times the transmission has acted the same way when cold: hard to engage 1st and 2nd when cold and shifter feels heavy (like churning thick butter when wiggled side-to-side). Before with the OEM fluid, wiggling the shifter was always the same, hot or cold. Now, even when the car is off, you can feel a bit of weight in it, until the transmission warms up and it feels normal. Engaging 1st and 2nd when cold requires to really push the shifter in. Never had this problem before with OEM. OEM fluid 1st was a bit notchy, but not enough for me to complain about - it never bothered me before. Today, after about 1.5 miles of local driving, at around 1-2MPH I tried to engage 1st, and it just didn't want to engage. It felt like it locked me out of the gear, so I tried to push and I felt a vibration in the knob and I heard a noise very briefly (my music was on, but it sounded like a quick grind). I immediately stopped trying to force it in, put it back in neutral and tried again, and the gear went in just fine. The grind couldn't have been more than a millisecond, but still, it pissed me off. I've never grinded a gear before. So is it the transmission fluid? Once it warms up, it's perfectly fine. And stays perfectly fine even after the car's been off for 4-5 hours. Is the fluid no good for our cars? Could it be a bit low?