[1badredbird]

Yep, it's you heater core. I had a leak in my 92 Toy's Rad, a big one. I went & bought the Copper sealer,(it looks like liquid copper when shaken) it's the most expensive sealer of the bunch, and worth every penny. Read the instructions, cause after it's sealed, You have to flush the system(no biggie) or it says it could possibly cause some of you rad's cores. But leave it in as long as possible, just for added insurance, I did. With that many miles, it's worth a shot,(versus changing your core!) I think $7 or $8.99. Mine is leak free for going on 1 year now, follow the instructions & it'll work. My leak stopped dripping, almost from a slow run, in less than 5 minutes. Whatcha got to lose, 9 bucks?
Good Luck! 'bird
PS: If you do try it, please let us know how it worked for you.