Occasionally while driving, my transmission whenever going into 3rd gear. I know the tranny was replaced earlier before I bought the car, but what could the grind mean? I'm going to try to put Synchromesh transmission fluid and see if that could fix it, but what else could it be?

-Matt

The grinding is from the synchronizers are going out or gone. First try synchromesh, if that doesnt quiet the grinding down then your synchros are gone. Cheap parts but expensive to have a shop replace them.

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I had the exact same problem. I think it was the syncros. Anyway i put some Synchromesh into the gear case and its been fine ever since. Stuff really works

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Awesome, I'm going to try that soon.

Anyone know how many quarts the transmission takes?

-Matt

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I had this problem with my Celica, It would grind going Into 3rd, 4th, and 5th. I adjusted the clutch pedal, the nut was to tight- and Its been fine ever since. I t does It once In a really great while.

To quote myself here about ST trans.

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Awesome, I'm going to try that soon.

Anyone know how many quarts the transmission takes?

-Matt
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If I recall my tranny took a little less than three quarts

just buy 3 to be on the safe side. I think its like 2 1/2 though.

i have the same thing, so avoid it, put clutch down, then put it into 2nd, keep the clutch down, then put it into 3rd, then take the clutch out....my gears dont grind when upshifting, but i need to do this when downshifting

that stopped my grinding problem....lol

i dunno if there 2 sets of syncros, 1 for upshift, 1 for down, i dont think so but not 100* sure

So my 3rd gear only grinds when my transmission is cold. But when it's at the correct temperature it doesn't grind at all. It rides perfect. The previous owner put in a new clutch about a year ago. I topped off the tranny with valvoline gear oil after replacing my passenger axle. I was thinking about maybe draining my tranny fluid and fill it up with Penzoil synchromesh. Any clue?

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Yes I would try replacing the fluid first. Make sure to use the correct viscosity, its 75W-90 I think but definately double check that. And dont overfill it. 3/10s of a quart over WILL make it work incorrectly.

Maybe you have something like 125 - 140 weight in there(I cant remember the standard viscositys) which is thicker. The problem would only become apparent when it was mucho cold outside if you had to high a viscosity,.

My shifts better into 3rd when it's cold. After it starts warming up, it doesn't grind in, but it feels like there is a decent amount of tension. If I floor it in 2nd up to 3,000rpm and then shift into 3rd, it goes in without and trouble. I think my syncro is slowly starting to go.

Yea I use 75w90. That's what was recommended to me by by local Toyota dealership. How much quarts does it take to fill a GT Manual granny anyways? I was guessing somewhere around 2 quarts?

It's just part of it. My uncle has had nine 6th generation Celicas and five of them would grind going to 3rd. The grind being more prevalent when downshifting. It's due to the synchronizer having gone out. The only thing you can do is have it replaced. Personally wouldn't bother. He even had a new transmission put into one, only for the syncronizer to go out in it again.

Wow i've had this issue the entire time i've had the car. Upshift into 3rd when it's below freezing causes it to grind. Downshifting into 3rd grinds about half the time. I thought it might be shift bushings since the rubber was deteriorated in them, haven't gotten to changing them since it too cold though. Also thought about having it rebuilt to find the cause but synchromesh sounds like a better plan.

Question: Are there better synchro options in case one has it rebuilt?

This post has been edited by cyberblader1130: Jan 28, 2013 - 1:23 PM

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I doubt it, probably have to get one custom made

If you have a GT swap to the E153 transmission, and if you have a ST swap to the C60 transmission. Problem solved.

This is why everyone recommends Pennzoil Syncromesh, specifically because it SEEMS to improve 3rd gear grind which appears to be the weakest link in our transmission. As the temperature drops the viscosity increases. I bet you cant even pour 75W-90 out of the bottle when its below freezing outside, so imagine how much worse a higher viscosity is.
A possible solution would be to fill your transmission with a lower viscosity in winter, and then switch back to 75W-90 in spring/summer. Viscosity is relative to ambient temperature(10W-30 motor oil is 200+ weight at room temperature but 30 at operating temp), and the syncronizers are designed for a very specific thickness. So by all means try a thinner fluid next winter and see if it solves the issue. The fact that the issue only occurs when its cold means your fluid is too thick.

And @ ILoveMySilly97, it is 2.7 quarts for the GT. Basically if you park it on a level surface you can fill it till it starts spilling out of the fill plug hole. The only way to overfill is if it is parked on a hill or you have the front end jacked up. They sell a hand pump that screws onto the bottle at the autoparts store, it is absolutely a must.

This post has been edited by Special_Edy: Jan 28, 2013 - 2:05 PM

Thanks for the infos. Going to change tranny fluid to penzoil when I get my coilovers in soon.

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Mine does it once it warms up though....
It shifts better when it's colder and still thick.