Chevy & GMC Vans

Hi all, First timer here. Been going thru about all postings, but need more info.
Van been sitting for 3 years, now after 120 miles, tranny stays in first. Checked fluid level
and added 2 quarts, no help. Not sure what to check next.
Was running a little sluggish before it quit, but getting me there and back.

92 Chevy Astro
4.3L Motor (Solid)
4L60/MD8 Auto
141,000 mies

I have very little knowledge of tranny's and would appreciate al the help I can get.

Drop the pan and replace the filter and put new fluid in. Inspect the bottom of the pan for chunks and pieces. My guess is your 700R4 with 141,000 miles is about due for a rebuild.

Drop the pan and replace the filter and put new fluid in. Inspect the bottom of the pan for chunks and pieces. My guess is your 700R4 with 141,000 miles is about due for a rebuild.

Ok Thanks.
Will be doin the filter change tomorrow.
The trans is not 4L60, whats the difference.
Thanks for the help.

The 4l60E is a electronic tranny and the 700 is not.