3rd Gear Crunch

#1
Good morning everyone. First time poster here since purchase of my corolla. Im having an issue with a grind/crunch when up shifting or down shifting into 3rd for about the first 10 miles every morning. Im here in south florida so it doesnt get too cold. maybe 50 at night at the lowest but usually 60-70. I changed the trans fluid with mt90 about 3 weeks ago and the problem persists. If i hold the clutch in for about 3-5 seconds i get minimal
i should point out that when i get to work i park for about 4 hours and then head back out and get no grinds at all. this only happens in the morning around 8.

just curious on what the problem could be based on what others have experienced.

2010 2.4L w/97k
 

ZeCorolla

I Love Corolla's!
#2
I have the same exact crunch. What I've heard is it's either the transmission fluid that causes it or it's the 3rd gear syncro. Toyota recommends that we use straight 75W manual transmission fluid and this supposedly will remove the crunch. Even if the outside temp isn't cold, the fluid in your transmission won't be at operating temp so it will cause the crunch until it's warmed up. Someone on ToyotaNation said they started getting the crunch after using MT90 fluid so this may be the case. If it's not the fluid, your 3rd gear syncro may be worn out and needs to be replaced.

I'm going to be changing my transmission fluid in a month or so to Royal Purple Syncromax which is a 75W oil and see if that helps since I recently bought my Corolla and it has 147k miles on it. However, the crunch doesn't bother me too much though since it goes away after 8-10 minutes.
 
#3
Hey thanks for the reply and getting back to me quickly. I noticed the crunch when I purchased the car and it was only on the down ships into the third. I figured replacing the transmission fluid Would help the situation out however after putting the MT 90 into the transmission the crunch started during upshifts. I have to replace the output shaft seal at some point soon so I will try a different transmission fluid and hopefully that resolves the issue I really do not want to open up the transmission to replace synchros. Sorry if my typing is a mess I’m actually talking to my phone again I really appreciate the comment
 

ZeCorolla

I Love Corolla's!
#4
Hey thanks for the reply and getting back to me quickly. I noticed the crunch when I purchased the car and it was only on the down ships into the third. I figured replacing the transmission fluid Would help the situation out however after putting the MT 90 into the transmission the crunch started during upshifts. I have to replace the output shaft seal at some point soon so I will try a different transmission fluid and hopefully that resolves the issue I really do not want to open up the transmission to replace synchros. Sorry if my typing is a mess I’m actually talking to my phone again I really appreciate the comment
I see, so the upshift crunch started after changing the fluid to MT90. That's really similar to the other situation I mentioned where someone else changed their manual transmission fluid to MT90 and that's when their 3rd gear crunch started. But yeah, start by changing out the cheaper stuff like transmission fluid before thinking about the syncros.
 
#5
Yeah that’s exactly what happened I should’ve just left the old oil in but obviously didn’t know any better and was hoping for better results as I have seen other mention they had. But I’m also glad that I did change out the fluid because the stuff that I drained from the transmission smelled horrible and was almost black I will try to use a different oil when I dig into that output shaft seal maybe next weekend
 
#6
I see, so the upshift crunch started after changing the fluid to MT90. That's really similar to the other situation I mentioned where someone else changed their manual transmission fluid to MT90 and that's when their 3rd gear crunch started. But yeah, start by changing out the cheaper stuff like transmission fluid before thinking about the syncros.
Also do you know if the transmission for the 2.4 is the same as the 1.8? I checked the owners manual and I see they have different fluid capacities 2 quarts versus 2.6 quarts I’m not sure if that’s just a variance in the transmission or if it’s a different transmission itself
 

ZeCorolla

I Love Corolla's!
#7
Also do you know if the transmission for the 2.4 is the same as the 1.8? I checked the owners manual and I see they have different fluid capacities 2 quarts versus 2.6 quarts I’m not sure if that’s just a variance in the transmission or if it’s a different transmission itself
The transmissions between the 1.8 and 2.4 are different. The 1.8 has the C59 5 speed manual while the 2.4 has the E351 5 speed manual and the E351 does take more fluid at 2.6 quarts.
 
Top