T56 says no overdrive
#1
11 Second Club
Thread Starter
iTrader: (3)
Join Date: Jul 2005
Location: Daytona Beach, Fl / Stuart, Fl
Posts: 215
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Well, last Friday when i was driving home from dinner i went to shift into 5th and it wouldn't go in, kinda like i wasn't using the clutch. So I went back to N and pumped the pedal a few times and it felt fine, went into 3rd, and then 4th, with no problems. Tried 5th again and it just made this awful grinding noise but i was able to get it into 5th. Once in 5th the gear shifter was really lose, so i tried to shift into 6th and there was nothing, like empty space. I pulled back on the shifter and i could then feel it grinding trying to go into 6th. All the other gears feel normal and i drove the car back to my apartment and thats where it sits, awaiting me to do something to it.
Just wondering what you guys have to say about it, and what would you recommend?
02 Z28 with just over 70k on it
Just wondering what you guys have to say about it, and what would you recommend?
02 Z28 with just over 70k on it
#3
TECH Fanatic
iTrader: (20)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
i would say its time to open the trans up.
5th and 6th gear are on their own counter shaft extension and their own shift rail. the trans needs to be opened up to be looked at and inspected.
There are some snap rings located on the shift rail for 5/6 that if broken could cause a problem that your are explaining.
5th and 6th gear are on their own counter shaft extension and their own shift rail. the trans needs to be opened up to be looked at and inspected.
There are some snap rings located on the shift rail for 5/6 that if broken could cause a problem that your are explaining.
#7
Banned
iTrader: (60)
Join Date: Mar 2005
Location: Adkins - Tx
Posts: 2,693
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
The problem could be a few things but considering that both 5th and 6th gear went down , you might have stripped the main shaft and the upper 5/6 gear gear . This is pretty common in higher mileage cars or with cars that the driver likes to lug around in the higher gears and not down shift to keep the car in the power band .
Trending Topics
#8
TECH Regular
iTrader: (5)
Join Date: Nov 2001
Location: Washington Crossing, PA
Posts: 422
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech20year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Originally Posted by thesource
This is pretty common ... with cars that the driver likes to lug around in the higher gears and not down shift to keep the car in the power band .
![Winky](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_wink.gif)
#9
Banned
iTrader: (60)
Join Date: Mar 2005
Location: Adkins - Tx
Posts: 2,693
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
The main shaft where the 5/6 gear is only half splined instead of a fully splined contact area . The 5/6 gear is designed the same way . Once the splines get some wear on them , the gear starts to rock back and forth on the shaft allowing it to further wear and eventually strip completely . When you lug the car , it creates more load on those gears and increases the wear . The after market mainshafts I use are fully splined in that area as are the 5/6 gears so it has more of a contact area and are less prone to wear as quickly .
The T56 is by far my favorite passenger car transmission but does have a few flaws . Once those are worked out , its an awesome multi purpose transmission .
The T56 is by far my favorite passenger car transmission but does have a few flaws . Once those are worked out , its an awesome multi purpose transmission .
#10
TECH Regular
iTrader: (5)
Join Date: Nov 2001
Location: Washington Crossing, PA
Posts: 422
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech20year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Well, after 105K miles and plenty of lugging, I'm taking the trans out of the car today (I have a similar, grinding 4 to 5 issue, and I can't even go 6 to 5 no matter what I try). I have almost 200 track passes on the car, so I had expected that any of the gears 1 through 4 would have checked out first. I was confused as to why 5th would go, but now I have a better idea. At least I have something to look for when I open it up. Thanks!
![Thumb](https://ls1tech.com/forums/images/smilies2/thumb.gif)
#11
Banned
iTrader: (60)
Join Date: Mar 2005
Location: Adkins - Tx
Posts: 2,693
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Just take a look at the splines inside the upper 5/6 gear and the mainshaft as well . Some wear is to be expected but if there is say more than 50% of the spline rolled over , I would probably change it given the driving habits you have . Another good indicator is if the gear just slides off the shaft when you are taking it apart . Usually you want them to be pretty snug and require a large puller to remove it . When they are new , they are super tight on the shaft because part of the mainshaft is a press fit and the other is splined . The aftermarket replacement shafts are fully splined as are the 5/6 gear . Most of the time they are super tight to put together and I usually put the mainshaft on a lathe and with some emory cloth take a little bit off the total OD of that area . I also take a little bit off the ID of the gear so that they press together with a little force but not too much . Once you install that shaft , you should not have to worry about failure in that area again or atleast I have never seen it happen .
#13
Banned
iTrader: (60)
Join Date: Mar 2005
Location: Adkins - Tx
Posts: 2,693
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
If you have ever seen a worn axle shaft and the area of the carrier where it makes contact , this is sort of the same situation you will be looking at on these two parts . Don't freak out if there is some wear on the parts , there will be . You just have to determine whether its enough to worry about or will it be ok to reuse . Alot of people just change everything that shows a little wear on it and in my opinion is a total waste of money . A good builder knows the difference between parts that will work and parts that will not work when reused . A parts changer just changes the part and never gives it a second thought ...........