2000 Ranger Transmission Slipping
 

My (late) fathers' Ranger sits in Moms' garage most of the time. I use it from time to time to keep the cobwebs out of it. She told me some time ago that when she took it to be serviced they told her one of the fluids was dark, she was not sure which one. Yesterday morning I took it up onto some property we have in the family and the transmission started slipping. I had no where to turn around and had to drive it more than I knew I should have. The was some smoke coming up between the cab and the bed. The fluid was full and I drove it gently downhill or flat across town and back home, it was fine. I was going to take it to a local shop to have it flushed, instead I think I will do a fluid & filter change. I want to see what there is in the pan. Worst case scenario, the transmission is toast. How do I find out what transmission is in it? The pickup has 42,000 gentle miles on it.

Could be a 4R44E, or 4R55E, door tag should tell which.

I think the letter code is D.