The factory (although rebuilt back in '97) Super T10 in my '82 Z28 locks in first gear on hard launches at the track.It has done it to me on the street as well from time to time.The motor and trans mounts are new polys, so I would have to rule out any weird drivetrain twisting.The shifter is a Hurst Competiton Plus that was installed new when the trans went back in in late '97.I have installed new bushing kits yearly and made sure it was adjusted properly.If I try to launch at anything over 3k rpm...not even dumping the clutch,slicks or street tires..I go to pull 2nd and the shifter just will not move!!After I got back to the pits I crawled underneath to see if any of the shift arms were out of whack..no.They look as they should for the car being in first gear.This happened on 2 passes and occasionally on the street.Does anyone have any idea what may be causing this??It seems to be internal from all checks each time it had done it.Nothing external was out of whack.The only way I am able to get it unstuck is to force the shifter back and forth and it sometimes will pop out of gear..otherwise I have to go underneath and move each shift arm back and forth a few times and then fight with the shifter to get it to pop out and go into neutral.I run Mobil 1 synthetic gear oil in it as well.Please help..I don't wanna go auto but this trans is forcing me.And I have no budget for the 6 speed conversion I am dying to do.

 

How long has it been doing this? Did you set the stops on the shifter correctly? the Slider may be going too far forward and is getting jammed. You may have to pop off the side cover and inspect the 1-2 shift assembly. Keep us posted.

 

Ironically..it's been doing it since I had it rebuilt now that I think back on it.It has just progressively done it more as the years and miles have gone by.I used to think it was the shifter.I had it rebuilt by Hurst a year after installing it (the shifter) swearing it was to blame with no change.Still did it.I think it has to be something internal.I know squat about trannies..especially 4 speeds so even if I was to pull the side cover off...what would I be looking for in the 1-2 assembly?I just wanna try and it fixed so I can make at least two more visits to the track and enjoy cruising the car the rest of this summer.Then I have to decide what to do about a trans.I have that TH350 waiting to go in..just can't get myself to swap the auto in.I love shifting!!!

 

maybe a bent shift fork or rod on the inside?

 

Could very well be.I have to pull the side cover off and see if anything looks...off.The only thing that tells me no..is that on an ordinary drive it shifts fine.The only time it gives me trouble is the occasional hangup on random hard launches/take offs.

 

It sounds more like your 1-2 syncro assembly is binding under full load. If it has been doing this since it was rebuilt I am going to point toward that. It may be a defective part that was installed.

 

That sounds more than likely something that it may be.I have to beleive it is internal.I now just have to debate to rebuild the T10 for now..or build the TH350 and swap over for the next two years or so till I can go with a 5 or 6 speed conversion.

 

Super T-10s are pretty simple. There are no rods inside the trans for shifting like a T5 or T56. The side cover houses the shift mechanism. Basically it's two forks, two scissor arms, and some springs. These things almost never screw up. Take off the side cover and move the linkage. If everything is smooth then there's no problem with the forks or internal linkage look elsewhere. Check the forks for being bent, that could be the problem, but with the cast iron forks it isn't as common as with the aluminum forks in T5s. Unless the shifter stops weren't set correctly and allowed overshifting.

The 1/2 synchro assembly consists of a hub with 3 dogs and 2 clutch springs, surrounded by a sliding sleeve. The two brass synchro rings sit on either side of the hub. Then each gear has a set of engagement teeth that are the same as those on the synchro rings. Check the teeth on the synchro rings and gears for wear (look for shiny metal, metal that looks pushed out of shape, and teeth that don't come to a point). Check the slider action. If it sticks you've found your problem. This is tough to do with the trans together, but you should be able to get some idea. The 1/2 assembly are the gears closest towards the tailshaft (the 1st and 2nd largest gears on the mainshaft (top shaft)). The sliding sleeve sits betwen the gears and has a groove to accept the 1/2 fork.

If you want to send it out PM me. I've rebuilt tons of Super T10s and Muncies (very similar in design).

 

What do you get for a T10 rebuild?

 

I have a 82 Trans Am, and my car did that also. What it was, was the tourque arm pushing up against the shift linkage that wasn't letting me shift out of first. I put a 1/2'' spacer on the torque arm mount and stopped immediately.

 

Interesting!

I have an aftermarket adjustable torque arm on the car..so I will certainly look into that!Thanks..

 

Just wondering how you made out.

 

Haven't even had a chance to look at it.Been busy swapping the intake out and a few other lil areas that need attention.As soon as I get a chance to look at it I will post back with my results.Thanks for reminding me though..lol.Almost forgot to look at it...

 

Is it just hanging up under a load?? Mine shifted fine through 1st and 2nd driving normally, but if i got on it, it would bind up and stick in first.

 

EXACTLY what it is doing...fine under normal circumstances...lock up in first gear 8 outta 10 times if I attempt to get on it aggresively!

 

Yea I'd bet money that's what it is. Just put it up in the air and leave it in 1st. You'll see it right away. I think i used two half inch spacers can get them at just about any hardware store.

 

Endless summer, can you expand on that? You mean space out the entire torque arm bracket? That's held to the tranny with 3 bolts right? So i'm thinking, 3x 1/2 sleeves? (or a stack of washers?)
Or am I thinking about this bass-ackwards?

 

Yea I had some 1/2'' spacers (a stack of washers would work) between the tq arm mount and the tranny. Brought it out a little bit. What was happening was the shifter arm was binding up against the mount when I would get on it from a dig. Since then, I've installed a hurst shifter and removed the spacers. The hurst shifter arms went clearly around the tq arm with NO interference. Definately would reccomend getting the shifter, it's a hurst comp plus. Man it has real short and precise throws.
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Hope that helps.

 

Hmm, I already have a hurst super comp shifter. Damn.
Well i'll take a look at it, and see if it could possibly be binding. If so, i'll give that a shot, i've got a bunch of extra washers around.