99 Silhouette speedo works, but van won't go

[72mino]

Van has 170K miles, I've had it for about 4 years and haven't had any tranny problems until now. I put it in gear and the speedometer works but the van doesn't move, then grinds when put back in park unless the van is shut off first. The passenger side half shaft can slide in and out of the tranny like there's no snap ring, which I haven't had a chance to pull it all the way to see for sure. I wasn't driving the van at the time, so I don't know for sure what happened, though I am guessing he went from reverse to drive while still moving backwards but won't admit it. Any thoughts???

Dustin

[Tech II]

If the speedometer moves, but the van doesn't, and the axle is not engaging the tranny, then it's no different than if that right wheel was slipping on ice and the left wheel was not moving......something is broken causing the axle not to stay in engagement....

[72mino]

Thank you for the response Tech II, but I already knew that much. After re-reading my post I guess I should have been more clear. What likely would have broken, and is it (or any of the possibilities) repairable in the van or would the cradle definitely need dropped. The van isn't worth putting much into, but I don't want to part it out or sell it as a parts car if it is something I could repair in place.

[gmtech1]

Could be the diff carrier, output shaft, sprocket(s), ect... the trans will need to come out and be torn down to find out for sure. If something broke, then there are pieces and parts that need to be cleaned out. At 170k it would be best just to do a complete overhaul when its out, or just replace it. Either way the cradle comes out.

[72mino]

Thank you GMTech1. That's not what I wanted to hear, but it is what I was expecting. The van isn't worth that much work, I paid 2K about 4 years ago already rear ended and now the head gaskets are starting to seep. I will just part it out or sell it as a parts car. Thanks again for your time and knowledge.

Dustin