Shift Problems

[Bob7z7]

Hello all...
I currently have a mid 80s lockup 904 tranny in my Scamp which I picked up cheap off Craigslist on a gamble. Story was it got pulled for a project that didn't pan out and sat inside drained and with the bands backed off.
Well I got all the engine issues worked out so I backed her out of the shop and went for a quick test run. Ran into some issues..
Whenever the car tries to shift into second the wheels seem to lock up, then it back back out and rolls for a bit and then locks up again. This is demonstrated well when coasting downhill when the car will go between reluctant rolling and the tires skidding as it coasts down.
Anyway, our guess (not being tranny guys...) was that it might be not disengaging first when it goes to make the shift from first to second, and both gears are engaging making the wheels lock, so we were thinking maybe a blockage in the valve body from sitting...
Is this completely off base and/or does anyone have any other theories?
Also I have a known working 904 from the '73 slant which was in the car before the swap. Will the vlave body swap over for testing purposes or will the fact that the small block 904 is a lockup prevent that?
The 904 is only in there untill I find/can afford a 727 and 8.25 rear, so I don't really want to throw a lot of money at it.
Thanks in advance...

[John Kunkel]

What do you mean when you say it sat inside with "the bands backed off"?
Was the band adjustment checked before running it?

The problem you describe could be a locked up rear band, pull the pan and check it for freedom of movement.

[Tarrbabe]

I had a 727 that lost the materal off the rear band and wouldn't release. Same results everytime it shifted to second, rear wheels would lock up and almost wrecked me the first time it happen. The driver of the car behind me let me know I was number one in his book also.

[Bob7z7]

DA'OH! Rookie mistake... when I torqued down the low/reverse band I forgot to back it off. So I cracked her back open, retorqued it, and backed it off the 4 turns the book told me too. Now I don't seem to have first gear. I was gonna tighten it in to 2 and a half turns and give it a shot... sound about right to you guys?

[John Kunkel]

You don't need the rear band for 1st gear; if there is no 1st gear with the shifter in Drive but there is 1st gear with the shifter in (1), the sprag has failed.

[Bob7z7]

When the band was overtightened I had first gear in both drive and 1st position. Since I've loosened it there is no first gear in drive or 1st.

[Bob7z7]

Any thoughts? I'd like to have first gear back and I'm stumped...
Again, when the band was overtightened I was stuck in first. Now that's its backed off correctly I do not have first in drive (it starts in 2nd) and with the selector in the 1 position it holds the vehicle still but revs like its in nuetral. reverse works fine.

[mopar413]

I had the identical problem,lockup the rear wheels when it shifted into second gear,(scary) back in early 90s,but it was after i installed one of those great G.E.R. valve bodies..JUNK!