'84 300TD 722.315 Transmission Problem
 

Hello all,
I posted a couple weeks back about this problem. The car would shift strangely and intermittently go into neutral (no drive). I had checked the fluid level, vacuum, and bowden cable. Well, after doing these checks (and not changing anything) the car drove and shifted fine. Being transportation desperate at the time (My old Saab model 96 stripped the timing gear last week) I went ahead and drove it....worked fine for about 300 miles. The first symptom happened again while cruising on the highway at about 50mph. The car would suddenly downshift down to 3rd while going downhill with light throttle...it would only go into 4th if I accelerated to 65mph. Later, when I took off from a stop it appeared stuck in first, then lost drive. After pulling over (coasting) and stopping for a minute, it would go again. Luckily this happened 2 miles from home.

I've removed the pan and filter. (changed both last year).
The fluid smells a bit burnt...but there don't appear to be particles in it. I'm thinking the pump may be intermittently sucking air due to a fluid restriction....could there be another wire screen in the transmission that may be clogged? (other than the filter).
The filter I took out was a Napa (non Mercedes...the one I had ordered last year was the wrong filter)...maybe this is the culprit, although after blowing through it...it does not seem restricted.

Shifter bushings appear tight.

Thanks,