Thinking I may be in need of a Dr. Evil clinic before too long.

Driving home - leaving a stoplight. Loud thunk/crunch and popped out of first.

I'm thinking "that's odd" - try to put it back into first and no dice. Get the rest of the way home using second to start (with a noticeable whine at lower revs). I go to put it into reverse and that's gone too.

Well, I've got a couple spare boxes in the barn, and short of better ideas, I may try and swap one of these in, I'm pretty sure I cooked something.

I betcha you pull off the tail end and you'll find some parts fall out!

But that happens even if there's nothing wrong

really?

I actually know something and stugray beats me to it.

next time, maybe.

randal

Hmmmm. I would look externally first. No reason R should go too. The only way I can think of both 1/R to do this is if the bolt pinching the 1/R fork came very loose. Not likely.

Check coupler at fire wall, cone screws fore and aft.

If input shaft broke off at 1st gear, it would eliminate 1st and reverse.

Jon B.

I had the same thing and found the speedo drive gear poking out the tail of the trans. It was time to upgrade to side shift on the 72 anyways.

Ya, that too. When I read, " try to put it back into first and no dice" I assumed that it would not go in, not that it was gone. With the end of the input shaft gone you still get the feeling of going into gear as the slider still moves fore and aft and still engages 1st big gear.

Westo2, do you get any feel of anything when shifting? If you do and no gear then Jon B nailed it.

Can't be sure that's what happened, but sounds likely given loss of reverse.
If it did, then broken shaft w/gear would fall to bottom of endcover, and could block movement of 1/R sleeve as well.

Jon B.

Opps

Nothing visually out of sorts from the outside.








Yep - still feels like I'm engaging 1st and reverse through the shifter, but no go when I come off the clutch. I figured it had to be internal, as I also have no issues from 2nd to 5th, aside from a lower end whine/groan that I hadn't noticed below 3k RPMs (which may be more in my head than anything - I was hyper analyzing noises after the big bang).

If it is indeed the input shaft - what am I looking at for a job? Could it still be driven in this case, or is a chunk of the shaft likely rattling around in the transmission waiting to do more damage? Repair is much easier if I can get it to Syracuse and put it up on a lift rather than laying on my back in my driveway in Buffalo. I do have Dr. Evil's DVD - I suppose it's time to dust it off and start reviewing some notes. And - forgot an important point - dealing with a tailshift transmission.

Thanks all.

DONT drive it. Your input shaft bearing is gonna give out if it has not already. I will try to take a pic of what is going on if I remember when I get home. This is a hard down conditions and I fear that Jon B was on the money. Might as well pull the gearbox.

As for cost to repair, that will be all over the board depending on shop/person. I am out for the next month and a half due to a move or I would be glad to help. If you can swap a core in for now, I can help you after. If you just want that fixed and nothing else, I can do that for the cost of parts. You can drive it down and do it yourself and I can guide you if you like.

Thanks for the input - so far, it was just about a mile from where it went to my driveway, and it's been parked since. Although the input shaft bearing hasn't failed, I would imagine this would be a "replace it while you are in there" part, right?.

I'm on the fence as to how to proceed going forward. I've got a couple tail shift boxes and a side shift (all in unknown condition - came into my possession with a truckload of parts). With the kids back in school and fall setting in, I'm tempted to just get it put away in storage and either deal with it in the spring, or pull the box and deal with it over the winter.

Although it isn't quite the news I wanted to hear on this, it's along the lines of what I figured, and I appreciate the knowledge and feedback.

Who knows, perhaps I can wrangle a stop by down your way to get and educational experience and repair on a family spring break trip.

As usual - this board is awesome.

Check your clutch tube yet?
Weld break in the tunnel?

I've got full clutch performance in 2-5, and no change in pedal feel. I would think that if it were an issue with the clutch tube, it would be causing me problems in all gears.

Nope, when my tube broke it wouldn't got in first or reverse. All other gears were fine.

his shifter goes into 1st and reverse position ..... but nothing there.... no go.... no gonna be clutch tube.... gonna be parts loose that shouldn't be

Does not answer the question.

It would take a few minutes....

Checking it might find something, it might not.
It's all part of trying to diagnose it.

the problem is NOT that he can not get the tranny into 1st or reverse ie: grinding, the problem is when he puts the shift lever in to those positions and lets the clutch out the car does not move.

how could this possibly be a "clutch tube problem"?

either the 1/rev shift fork set screw is loose, the nut that holds 1st/rev is off and gear is off shaft or the main shaft broke at 1st gear.

Correct - no grinding, no issues getting the shifter to move into first/reverse - simply no power from the engine to the wheels when the clutch is let off. When it failed it was a pretty good crunch/thunk coming from the back, so it fits that something may have sheared/broken. I haven't had a chance to get the car in the air at all - just crawled under the back as far as I could with it on the ground. Nothing looks out of sorts externally, but I'll get it back into its native habitat on jack stands this coming weekend and poke around a bit more.

Again, thanks to all for the suggestions and diagnoses, I'll get this one back on the road before too long.