84 300diesel transmission slipping in 1st
 

i have a 84 mercedes 300d and the transmission slips in first gear sometimes. it is fine in all the other gears and about half the time it works fine in first but then sometimes it will slip and you will have to rev it up before it catches. i have changed the oil and filter and it is exactly the same. if anyone could point me in the right direction thet would be great

About your only hope is that you are low on fluid or too much vacuum is getting to the modulator. If you wish to test that pull the line to the trans off its connection under the hood. It should then shift very harshly. If it makes no difference and the fluid level is right, it gets worse.