dharris45

I've got a similar thread on the NCRS forum, but wanted to get additional opinions here.

When I bought my car, it had a 1963 T10D B/W transmission. I purchased a more correct T10-1C (all aluminum) 61 transmission and rebuilt it with a T10-1D cast iron maincase. This was my first transmission rebuild and I thought I checked everything correctly as I rebuilt it. I visually checked the main shaft for any twist and could not see any.

The one thing I didn't, and should have, was to see if the slip yoke would go all the way onto the output shaft end.

So now, I just put the engine and transmission into the restored car. I tried to put the driveshaft in this weekend and can't get it into the transmission far enough to connect the U-joint to the pinion yoke.

Advice from the NCRS forum is that the output shaft is likely twisted, which I suspect is accurate.

To do a little check, I installed the driveshaft into the 63 transmission that came with the car. With it pushed in until it stops with minimal force, the exposed part of the yoke measure 1 1/2". With the driveshaft installed similarly into the transmission in the car, the exposed yoke is more like 1 7/8", so maybe 3/8" more yoke goes into the 63 transmission.

When I tried to install the driveshaft into the car, it looked like maybe 1/2" more clearance was needed to get the rear U-joint far enough forward to get it up and onto the pinion yoke.

My basic question is, how far should the yoke slide into the transmission?

By the way, yes I believe I have a correct yoke for the 60 corvette, it has a 4 7/8" snout. And I can not see any obstruction inside the yoke.


Thanks,

Don

dharris45

Can anyone give me an idea of how far I should be able to push the slide yoke into the transmission? I'm not looking for an exact measurement, but since the splines in the yoke go all the way down inside, I am assuming that the yoke should slide all the way into the transmission.

I'm trying to determine if I have both a bad yoke and bad transmission main shaft or just the main shaft.

The yoke will not slide into either of my current transmissions. About 1 1/2" exposed on the T10D-1.

Thanks,

Don

dharris45

Another related question. If I find that my yoke is bad, I see that Paragon and Corvette Central now sell reproduction of the correct corvette slide yoke (4 3/4" long).

Anyone used one if these? any quality issues?

Thanks again,

Don Harris

Frankie the Fink

I'll take a shot. IIRC my driveshaft fabricater in Orlando (does a ton of hot rods and custom cars as well as original vehicles) told me you want at least 1" exposed at WOW (weight on wheels). This picture is with the driveshaft extended with the car on a rack and NO weight on wheels and with the original T-10. However I have the original rebound straps on the axles so the shaft will only come out so far while attached to the pinion. I doubt this is much help but the only picture I have...its a tough spot to photograph.

I have had my shaft in and out 6-8 times dealing with a yoke seal leak in the front and I always had plenty of clearance from the pinion U-joint when R&Ring the shaft. I'd say at least an inch. I have my original shaft at home in storage (I'm out of town right now) but could dig it out and measure it Saturday if you need me to.

dharris45

Thanks Frankie,

So it seems that if your guy is saying at least 1" exposed WOW then it should and could go in ever further. So mine should go in further that it does, 1 1/2" on the T10D and 1 7/8" on the T10-1D exposed and will go not further.

I sure hate to rush out and buy a yoke (which I can get the repro) and also try to find a correct mainshaft ( which is difficult to fine as I've been told). But I have not come up with a way to verify if either or both or good or bad

Don

wmf62

if you can wait, i suggest you wait til Frank can measure his driveshaft yoke, there are supposedly 2 different lengths of yokes.
Bill

1snake

Don,
The picture you posted clearly shows that the splines are twisted. The yolk should slide all the way into the trans.. Be careful when you do that as sometimes the exposed/rusted portion of the yolk can tear up the rear seal. Good luck finding a mainshaft.

Jim

wmf62

what pic? the only pic i see is Frank's.
Bill

1snake

It's on the NCRS site. It shows a slight twist right where the yolk ends and it's in the direction they all twist. I've seen them twist a lot more but his definitely has a twist. That's his problem. Here's the pic. he posted.



Jim

Frankie the Fink

Repost the pic of mainshaft. The yolk should slide in like butter with the seal providing slight resistance.

wmf62

in a word.... WOW

thanks Jim
Bill

Powershift

I would take some very fine wet/dry sandpaper or very fine steel wool with some WD-40 as a lubricant and clean up any rust buildup on the yoke. Then oil/grease to reduce future rusting.


Larry

1snake

I replaced one many years ago in a car I used to race and the shaft was twisted close to 1/4". I couldn't believe it didn't break. Traction is the root of all evil, and broken parts.

Jim

wmf62

IF push-comes-to-shove..., can he get by with a shorter yoke?
Bill

Pilot Dan

Jim is correct. With that being said, the main shaft can be replaced with a fine spline shaft (Muncie) and they make a longer fine spline yoke as well (reproduction) that works very well with it. Granted unless you are doing burnouts you may not need this, but I think a teardown and replacement of the mainshaft is in your future to fix this properly. Pilot Dan

ps I would highly recommend D&L Transmission on Long Island. Larry knows these boxes and has fixed tons like yours.

John McGraw

I used to race out of a shop up in Kansas, where the owner of the shop was just too cheap to buy good axles, so he went to junkyards and bought a load of them. He painted a white stripe down the axle, and after the race every weekend, we would pull the axles and check the stripe. When the axle made one full revolution of twist, we would throw away the axle and stick a new one in there! Big heavy car and 10" slicks, would make us go through at least 2 set of axles every season.


Regards, John McGraw

wmf62

the thought just occurred to me.....

if both transmissions are essentially identical and the yoke slid in far enough in its previous application then the amount the yoke slides in now should be sufficient....
Bill

dharris45

My Yoke is smooth and clean so it is not the problem. At least on the outside.

1snake/Jim answered the main question I had, and that was how far should I be able to slide the yoke into the transmission. Looks like it should go all the way in, so I guess I'll go looking for a replacement mainshaft.

What still has me a little confused is that I can not get the yoke to slide all the way into either transmission. I does go in further on the 63 T10D transmission, but still sticks out 1 1/2". Where on the T10-1D it sticks out about 1 7/8". I guess I can conclude that maybe both transmission have twisted shafts! I have not had the 63 transmission apart. It was in the 60 vette when I bought it. And for the life of me, I can't see any burrs or damage to the splines in the yoke.

Oh well, you live and learn. If I ever have to rebuild another B/W or Muncie I'll know to check the mainshaft closer and test fit the yoke. I'm not looking forward to pulling the transmission back out!!!!!!

Thanks to all,

Don

62Jeff

If it's relevant, my 62 successfully uses the short yoke because the correct long yoke will not go into my transmission - likely from the same twisted mainshaft problem.

dharris45

Yes, I got the original rebuild kit from D&L and actually have a call into Larry now. I see one listed on their website under the T10 parts. It $168 if it is correct.

He definitely knows what he is doing and was a lot of help before since I don't know what I'm doing.