I have a name brand T/D powerglide that I just put in my car a month ago. It has a total of 18 passes with no issues. Two weeks ago I raced a local bracket race and afterwards loaded car up and then went to out of town race Friday. I unloaded, warmed car up and was going to go tech in and car would not move. I jacked it up and with engine idling and trans in 1st gear the tires would not turn. In fact I could turn tires in either direction by hand. I put it in 2nd gear and tires would slowly turn in fwd direction but I could stop them by hand and even turn them backwards. With trans in reverse I hit the trans brake button and the tires turned in the fwd direction only and I could not stop them by hand.
Next I put a gauge on the servo port and it had 240 psi at 1100 rpm and 265 psi at 1400 rpm so the pump is good.
I pulled trans and the input shaft is good and no metal was in the pan. The selector valve was still engaged with shift lever. I put spare trans in with same convertor and everything works fine.
Any ideas? I will call the company in the morning to see if they can help but I am stumped.
Sorry for the long post, just trying to give as much info as possible.
Thanks, David

I would check the rearend-

I had a similar problem a few years ago.i changed the valve body and it worked fine.it appeared some trash got in it somehow.brand new trans

Footloose, he put his spare in and everything worked fine. I’m no expert but I’m thinking valve body.

only a guess, but I would check converter charge circuit based on given info.i am assuming you drove into trailer at last race.this would rule out broken parts. please post what you find after tear down.

if it is a hughes convertor there is a shaft issue.saw that last year.thinking it was a length issue.it was an engagement issue in the convertor.look at the very ebd of shaft may see a sign

Called builder today and they suspect possible drum failure of some kind or broken clutch splines. Said it probably something odd like that. Fortunately they have a vendor near me and they said take it to him and they will take care of it through him. It’s at his shop now so we’ll see.

yes i talked to the other david a while ago,i did have the top of the high gear drum break out on me last year,i know he will fix it

Might have ripped spines out of converter, especially if the transmission still has pressure.

Have one on the bench with the splines tore out of the converter. One quick way to tell, put the input in there and spin by hand.

Converter is good as is the input shaft. When this happened Friday afternoon I put spare trans in with the same converter and raced Saturday and Sunday with no issues. Haven’t heard anything yet and the shop that will tear it down is headed to a divisional race tomorrow so it will be next week before I know any more.

I had this happen several years ago, and it turned out that the pin that held in the bypass valve snapped and would allow the trans to build enough pressure for the trans to function.

So what did the trans. guy find ?

quote:

Originally posted by professr007:
So what did the trans. guy find ?

More important have they taken care of problem and under warranty?

If it made 240 at the servo then the pump and vb are working. The suspect would be the input shaft. I have seen where the input will travel forward as they float and go thru the spline of the converter and pull out of planetary sun gear. Inspect the rear of the input for burs on the end of the spline. Let me know if I can help otherwise.

Greg

The above happened to me last year on a combo I had been running three years.

Well so far there is no smoking gun. The internals all look brand new. A new valve body is on the way but it seems odd that pressure followed gear position.
Greg, I did not look at the end of the input shaft but now that you mentioned it when I removed the converter the shaft came out part way and would not go back in all the way. At the time I didn’t worry about it because I was going back with the spare transmission. I will call the builder tomorrow and ask him to look at the splines at the planetary end. If that is the problem what is the fix?
So far the company is standing behind their product.
Thanks for the help and I will update when I have more info.
David

Converter has to have a spacer welded into it to keep shaft from moving to far forward. FTI can correct your problem if that's it.

FTI Greg for the win! Talked to trans guy today and he found that the “wedding band” bushing would not go over the input shaft due to damage to the splines from the shaft moving forward. He had never seen this before. This is the only thing he found wrong so he is putting it back together. Next I will call converter guys and find out how this can be fixed.
This will be the next chapter in my book on things that go wrong with race cars!
Thanks for the help everyone and especially Greg for diagnosing it on the first try.
David

GREG and FTI are awesome and extremely knowlegable.