hard shift
 

OK, still finding new issues with my new sled, a 1980 300sd with 265,000 miles. It has a rebuilt tranny that's just about 2,000 miles old. The tranny shifts pretty hard from 1st to 2nd gear but the rest seem fine. Is this a problem starting or something that needs tuning?
Thanks,

Dan

Diesel Giant
 

Dan,
go to the Diesel Giant web page .. there is an excellent diagnostic page there on tranny shifting.
roberto

It's a vacuum problem. Likely too little vacuum to the modulator. There's a very very long thread on here which explains how the system works and how to adjust the vacuum and the modulator. Could be as simple as a disconnected vacuum line.

It takes a while to read through it but it explains everthing:

http://www.continentalimports.com/ser_ic20242.html

ok, I've read through a lot of the thread. Probably should have stopped before I got confused but oh well. I have found my vacuum diagram http://peterschmidtransmission.com/images/617_9 but I am unsure of were to start so tell me if I have the steps right.
1. test for Vac leaks.
2. test for 15-10 in pressure at idle on backside of orifice and 0 in at full throttle.
3. I am clueless at this point and need help.
My tranny only shifts hard between 1st and 2nd. Do you think just changing the orifice size will fix the problem or will I have to go deeper? If so what would be the logical first step?