Hello all,

I have been lurking about this site for some time now. Until today, never thought to register since most of the time if i have some sort of question or issue I can usually find it simply by reading the threads. This time, though, I haven't been able to so finally figured I'd join.
On to the issue at hand eh? I have a 98 cavalier with a 2.2l OHV (engine code 4) and a 3 speed auto transmission which has, for the most part, given me no real trouble over the years. That has changed a bit. A few days ago I was driving down the road at average speeds, 30-40 miles on an open road when after coasting along for a bit it suddenly lurched and clunked like it had slipped out of gear or something broke. I pulled over immediately and investigated. No apparent signs of what might have happened, but i had left my car running while i checked everything out and when i got back in, it was overheating. I shut it down and let it cool, added antifreeze (which i keep on-hand just in case) then since i was less than a mile from home drove it there.
The next day when i had time to tear it apart and look I was surprised to find it trying to roll away from me as i tried to take the lugs off. It was in park and still wanted to roll.
To make a long story short, because of that i pulled the axles, examined them,(no issues) I've checked and adjusted linkage and shift cables, no leaks in trans-axle to be found. replaced fluids and filter and since i discovered worn out wheel hubs I went ahead and replaced them while I had it apart. As far as visual inspection, everything seemed ok. so I put it together and took her for a test drive.
Ugly seemed all better for about 3 miles, then the clunking lurching again...no overheat this time. But I suddenly discovered I now had no reverse when trying to return home. putting it in park then reverse multiple times eventually gets it working. Tranny was my next suspect. But another thing I noticed is it now will start in park, but not in neutral so I'm wondering if maybe I need to readjust the linkage o maybe the pnp switch could be malfunctioning. Could a worn out pnp (neutral safety switch) cause these symptoms?
Anyhow enough of the rambling, I'm hoping someone might be able to tell me where to try next. Not really keen on putting a tranny in in winter. Really hoping that ain't it.
Any input would be helpful

Alost sounds like the differential. if the car is in park and the axles will still spin, the teeth on the spider gears are probably stripped. Thats probably what the clunking was


"Oil Leak ? What oil Leak ? Oh, Thats Just The Sweat From All The HorsePower!!"

Yeah started thinking that too. I managed to locate a 97 cavy that had been smashed up, went ahead and bought it for 175 bucks and plan to just swap out the transmission. What's in my 98 is a 3t40, this donor has the 4t40 so won't be just basic bolt and go, but for 175 bucks, worth the work I think. Thanks for the input, it's appreciated.

Managed to find a wreck with brand new quick-struts and a horde of other new parts, so I'll be swapping alot of parts.
Harness, console, cluster, shifter, axles, ecm, cables...am i missing anything i need for the swap? The donor car is whole so I essentially have everything I'll need but haven't torn into it yet so heads up on possible issues can't hurt...know what I mean?