Transmission Problem

This is actually my cousins vehicle, so I don't know as many details about this vehicle as I would if it were my own. But I'll try to best explain the problem as I possible can.

This is a 1996 Chevy Blazer. I know it has a V6 and I know its a 4WD. About 2 weeks ago he noticed his Blazer would not move when placed in gear (drive or reverse). Last week I had my mobile mechanic check it out, and he said the tranny fluid was low, "real low". At first he wanted to replace the strainer and whatever fluid was left in the transmission. But he decided against doing that because he feared if he removed the strainer and the transmission is bad, that would cause more havoc on the trans then there already is. So instead he simply filled the transmission with Lucas and transmission fluid. My cousin drove around fine for about a week, until he noticed the truck wouldnt move when he put it in gear again. Now hes having trouble getting his hood up so he couldnt check the fluid level, but I suspect the fluid is low again. He had it towed to Aamco, and they said they found 2 leaks and they would have to drop the trans just to see if they could fix it. the prices Aamco quoted ranged from $2,000 to $5,000. Now I'm not familiar with these vehicles. I was wondering are they prone to certain transmission problems??? I'll probably have my mechanic look at it again, but is there anything in particular he should look for? One more thing, before the mechanic put the tranny fluid in, there was smoke coming out of where you check the fluid level and put fluid in. Anybody have any ideas on how to procede next???

Thanks for taking the time to read this post. I know its quit long...

Answer to your question about these transmissions, they are prone to malfunctions. These transmission aren't that hard to rebuild, if you are mechanically inclinded. I rebuilt mine for around 400 dollars, and that was a complete rebuild.Sounds as if your clutches are worn out. It's poosible the sun shell rection gear is bad. Before I'd give Aamco that kind of money, I would call a junk yard and get a price for a used one. There are other places on the net where you can get them cheaper than what Aamco. The best advice I can give you is spend a little time researching on the net and locally. Fill free to ask as many question as you need. I'll be happy to help if I can. Aamco is over priced and over rated.
SC

I don't know how good these are, but if you go on Ebay and search for the blazer transmission you can find rebuilt ones for under a grand