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Discussion Starter #1
I just replaced my 6MT transmission, and shifting is notchy and crisp. However I'm having trouble getting into reverse. I can get the lever all the way to the left and partially forward to the point that the reverse alert beeps, but then I get stuck. I'm shifting from a complete stop. I've tried double clutching. I just have to go back and forth of neutral to reverse a handful of times before I luckily am allowed into reverse. Any advise?

I'm taking it very easy now knowing that the FJ 6MT is made of glass. Gentle slow shifts from now on. Are there any specific recommendations for breaking in a new transmission?

Background: So I got a new transmission after it rapidly deteriorated. 13yo. 97000mi. Mostly city driven with a few long trips. It was hard to get into gear. It would grind when shifting. The synchros, bearings, or both were dying. Being a 2007 MT, Toyota didn't feel the need to assist with the replacement, but in the end forked up a few hundred dollars. My VIN wasn't included in the TSB regarding the bearings. Clutch was fairly new so that was left in.
 

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OK...dont have a manual transmission, but I have owned plenty of vehicles with them. First is to confirm the shifter linkage has been adjusted properly and the bushings arent worn out or misaligned. I can tell you with my son's 98 Jeep Wrangler, some of the shifter bushing were worn out and making it difficult to shift. Did you install the transmission or did someone else? If someone else, first thing I would do is take it back to them and demonstrate the problem.

I certainly have never heard of having to break them in. My experience has been they either work right or they dont. And if it is not shifting well, it is either a shifter linkage or a fork issue (forks are what are inside the transmission and slide the gears around engage/disengage. Occasionally because the reverse gear is often non synchronized, that you have to put it in another gear first and then put into reverse (e.g. dont go directly from neutral to reverse). Second thing on reverse, is you sometimes have to just ease the clutch out to the friction point and it will drop into reverse. Dont really know who to describe it other than you have to play around a bit with engagement and rpm on a whole lot of manual transmissions to get them to go into reverse.
 

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I 2nd the bushing also. That was a constant problem with my FJ 55. My FJC was not happy once with a type of fluid I used one time. I don't remember what type it was but the synchro did not like like it. Drained it and changed to something else and I was very surprised in the difference. The bushing is cheap, fluid is cheap, try it. If you do it at the same time you can just dump the oil in from the top and not have to pump it in.


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OK...dont have a manual transmission, but I have owned plenty of vehicles with them. First is to confirm the shifter linkage has been adjusted properly and the bushings arent worn out or misaligned. I can tell you with my son's 98 Jeep Wrangler, some of the shifter bushing were worn out and making it difficult to shift. Did you install the transmission or did someone else? If someone else, first thing I would do is take it back to them and demonstrate the problem.

I certainly have never heard of having to break them in. My experience has been they either work right or they dont. And if it is not shifting well, it is either a shifter linkage or a fork issue (forks are what are inside the transmission and slide the gears around engage/disengage. Occasionally because the reverse gear is often non synchronized, that you have to put it in another gear first and then put into reverse (e.g. dont go directly from neutral to reverse). Second thing on reverse, is you sometimes have to just ease the clutch out to the friction point and it will drop into reverse. Dont really know who to describe it other than you have to play around a bit with engagement and rpm on a whole lot of manual transmissions to get them to go into reverse.
No linkage on the MT.
 

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New Transmission: Break in period & shift problems

There is a bushing on the bottom of the stick, a cup like dohickey

Know what, I may be confusing rides. Let me go look this up.

This thing


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"now knowing that the FJ 6MT is made of glass"

Wow, I've never heard of any issues with FJ manual transmission durability. I wonder what it was that actually happened with yours? Difficulty shifting could be caused by a leaking clutch hydraulic system not completely releasing the clutch.
 

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Discussion Starter #8
Thanks for all the input everyone. Brought it back and the technician (Toyota) had no problems. The shifting track that I previously used to get into reverse has changed. Before, I'd push all the way left, maintaining left pressure, and shifting forward. Now I push all the way left, then without maintaining left pressure, push straight forward to engage reverse.

Everything is much more notchy, but that's expected from a new transmission. I'll continue taking it easy and shifting nice and slow on this transmission.
 

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Discussion Starter #9
"now knowing that the FJ 6MT is made of glass"

Wow, I've never heard of any issues with FJ manual transmission durability. I wonder what it was that actually happened with yours? Difficulty shifting could be caused by a leaking clutch hydraulic system not completely releasing the clutch.
Look at this transmission forum. There's a few long threads about the 6MT synchros and bearings failing at very low miles. Toyota issued a TSB but its doesn't resolve that there's an inherent design flaw that will cause 6MT's to fail prematurely. The transmission is made by a large manufacturer that supplies many other brands. A mechanic I got a quote from actually said his wrangler has the same transmission and had the same failure as my FJ.

I wouldve never expected such poor quality in a toyota. A transmission failure <100k miles is inexcusable, and will make me question buying a Toyota as my next vehicle.
 

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180K mi on my 6MT and all is well......still on the OEM clutch.

From observations/conversations over the years a lot of reasons for an early demise of the 6MT is poor shifting habits, poor maintenance, fluid choice.
 

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Discussion Starter #13
I just have to shift to neutral->2nd->reverse in order to easily get into reverse. Everything is still very notchy.

There's a very long thread in this transmission forum that goes into detail about the 6MT failure. There's a design flaw that puts pressure perpendicular to an aluminum (soft) shaft. Over time that causes wear and tear. It's not a fluid or user error. It's a design flaw. It seems some more more blessed than others in regards to transmission life. 6MT's were only 1/10th of the production so getting a lot of input from toyota is tough. This tends to manifest around 100k but has been seen earlier.
 

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I just have to shift to neutral->2nd->reverse in order to easily get into reverse. Everything is still very notchy.

There's a very long thread in this transmission forum that goes into detail about the 6MT failure. There's a design flaw that puts pressure perpendicular to an aluminum (soft) shaft. Over time that causes wear and tear. It's not a fluid or user error. It's a design flaw. It seems some more more blessed than others in regards to transmission life. 6MT's were only 1/10th of the production so getting a lot of input from toyota is tough. This tends to manifest around 100k but has been seen earlier.
I think you are confusing transmission failures with clutch throwout bearing problems. There is no "aluminum shaft" in any Toyota manual transmission.

If there is any "design flaw" or "design weakness" in the RA61F transmission, it has been with the throwout bearing, and the way is supported and guided. The throwout bearing is located outside the transmission, between the transmission and the clutch. There is a thin-walled tubular extension (quill), integral with the aluminum front transmission housing/bell housing, that serves to guide the throwout bearing. In some cases, movement of the throwout bearing against this extension causes noise and/or excessive wear of the extension. It's not clear why some vehicles seem to have repeated throwout bearing problems, and others do not.

Internally, the RA61F is a very robust and reliable transmission, so it's not clear where you are getting the idea that the transmission is "fragile as glass". I'm not sure that I have ever seen a post on this forum where a manual transmission actually suffered a true catastrophic internal mechanical failure (broken shaft, broken shift fork, sheared gear teeth, failed INTERNAL bearing, etc.).

However, like all manual transmissions and clutches, it can be abused by improper operating technique. Many people do not really understand what synchronizers are, how they operate, and the shifting technique that will maximize synchronizer and transmission life.

By a huge margin, he most common source of manual transmission shifting problems and synchronizer failures ("grinding gears" while shifting) is a clutch that doesn't fully release. I would have strongly recommended that the clutch and throwout bearing should have been replaced at the time the transmission was removed.

As for break-in and fluid change, like any mechanism a transmission will shed wear debris during the first few hours of operation. I'd perform an initial fluid change at 3,000 miles, and every 30K miles thereafter.

Just out of curiosity, exactly what were the problem symptoms that your transmission was exhibiting?
 

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Discussion Starter #15
Thanks for the thorough explanation. I have some mechanical knowledge but can't pretend to have the depth needed to understand the inner workings of my problem.

I was experiencing grinding going into each gear 2-5. I was told that it was most likely synchro failure and that either a rebuild of replacement was best. As toyota offered to help with the cost of a direct transmission replacement, I opted for that vs a rebuild. The clutch was new at around 80000 miles. Upon inspection during the transmission swap, the clutch was inspected. It was not suggested that a new clutch was necessary.

I'm not sure the the throwout bearing that surrounds the quill was inspected. I have to wonder if the true problem was the clutch mechanism, and that the damage was inflicted on the synchros because of poor engagement/disengagement of the clutch.
 

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(snip)

I was experiencing grinding going into each gear 2-5. I was told that it was most likely synchro failure and that either a rebuild of replacement was best.
""Grinding" going into EVERY gear is almost invariably caused by a seriously dragging clutch.
 

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Discussion Starter #17
The clutch assembly was inspected when they replaced my transmission. At least when they looked, everything looked just fine.
 
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