1993 Olds Delta 88 Transmission slipped into neutral on it's own. PLEASE HELP ME!!!

Hello,
This is my third post about this car already and I have only had it for 2 weeks now. Now today I was driving my grandmother to the store, and I slowed to stop at a red light. When I got down to about 5 MPH the transmission slipped into neutral on it's own. I thought maybe this was a fluke so I shifted it to reverse, then back to drive, and proceeded on. Came to the next red light, and it happened again the same exact way. So I came home and called the local tranny service center, and the mechanic said the transmission is most likely shot. So about an hour and a half later I deceided to go out again to see what would happen. I went the same exact route again, and nothing happened.

Now a little history,
Since I bought the car I changed the Spark Plugs, Wires, Coil Packs, changed the tranny filter/fluid. The car has 116,000 miles on it, and the fluid was never changed or serviced in any way in all that time. But... the fluid was turning brown however there was very little sludge to soeak of in the pan, and very little metal particals. I've seen a lot worse on every transmission I have ever changed the filters, and fluid on before.This is why I am puzzled as to the transmission acting up like this. It was not slipping, or anything. It did seem a little sluggish on take off before I serviced it, but that is normal when the fluid gets to the point of turning brown. I pray somone will tell me that this is just a fluke, but most likely not. Please if anyone out there can help me, I would greatly appreciate it!

ok, so im not much of a transmission expert, but i do know that they're risky business after being neglected. i heard somewhere that the lubricant in trans fluid never wears out, it's just the additives in the fluid that break down over time and they don't protect the trans the way they should. over time, a certain additive, an anti varnishing agent (keeps crap from sticking to the parts in your trans) breaks down and allows crap to stick to the inside of your transmission. over time these hunks of crap solidify and actually become a part of the transmission. when you changed the fluid, those hunks probably came off because of the anti varnishing additive.. and they cause some other kind of problem that i dont know enough about to talk about.

im sorry i cant help you fix the problem, but anyway now you know that its risky business to buy a car with that many miles and no trans service records...

and hey, if i'm completely wrong, im sorry.. this is just what i heard.. so all you AFers dont yell at me if im wrong.. just tell me nicely :p

Actually you are right on the money. I was told pretty much the same thing by the transmission service center here. He said that changing the fluid was probably more harmful than helpful at this point for the same exact reason you gave. I was just kind of hoping that the slipping out of drive was sonething of a sensor nature, and that someone here could let me know. Thank you for taking time to answer though, and share this with as many as you can so they don't make the same mistake I did.

I would check a few things first if i were you when it comes to the transmission, when you pop the hood you'll notice the trans sits on the driver's side and the trans-axle runs behind the motor. There will be a rubber diaphram that is the cruise control (vaccum driven) and behind that runs a cable attached via a plastic knob to the top of the transmission. This is where it gets fun. Find a buddy to sit in the car with the ignition in the steering and trans-released position, but not running. Have them shift through the gears and watch the arm go back and forth, it should click and move smoothly. Stop at each position (particularly drive in your case) and try to wiggle the cable, and the lever, if you can slide it easily into neutral and there is no click then your problem isn't with the internal transmission but shift linkage. Solutions for this are to get a replacement spring and arm and replace the linkage piece on the trans, (Be VERY careful as the plastic loop that holds the cable to the lever is easy to crak when removing the cable to change the lever) or, take it to a local shop and see if they can replace the trans linkage on the transmission and show them what was wrong with it. Good luck and cheers!