I have a stock 86 with 305 and Auto. Transmission shifts through all gears but the shifts from 1-2 seem harsh. Was this normal for them or is this an issue? If you hit the gas hard the shifts dont seem as harsh. I notice harder shifts more in normal driving mode. Normal?

 

If the transmission is stock, good possibility that the 2nd accumulator spring is broken. More common then it should be.

RBob.

 

Would this also cause hard engagement going from park to drive?

 

No. The 1982 - 1986 700R4's did not have a forward accumulator, the reason for the harshness here. Starting in 1987, all 700R4's had a forward accumulator. The forward accumulator absorbs the shock of neutral to drive engagement. Higher than stock idle settings and very tight torque converters make this engagement worse.

 

So the hard engagement from park to drive is not the accumulator but something else? What would cause this? Idle speed is low. 600 rpm is all,

 

Read above.

 

Interesting, I have the same issue with my 87 GTA. The shift from 1-2 is abrupt (read a bit jolting), but then 2-3 and 3-4 are smoother.

 

So after driving it again and paying close attention, 1-2 shift is soft. Didnt notice it before so thought it was 1-2. 2-3 is more noticeable and 3-4 is harder yet. Thoughts?

 

What is the normal shift rpm for a stock 700R4 from 86?Under normal driving mine seems to shift through the gears fairly fast but maybe this is normal. It seems to go from 1-2 then 2-3 and 3-4 all before 30 mph. Is this normal?

 

Same for my car 86 305.

According my experience with other older GM cars , this weekend I'll do the following:

-Replace Transm. filter
-Flush old ATF with new Dexron III ATF (aprox. 12 quarts with engine running, opened transmission oil cooler line and refilling by dipstick + an assistant changing Tr. lever from park to 1 and viceversa)
-Addition of 2 Lucas Transmission Fix bottles.

After of run test, fluid level check, etc. I'll start with TV cable modifications in adjustments lenght, from short to long and a normal driving test for every position adjust.

These different TV cable adjust could modificate engagements from smooth to hard / short to long. I'll test them next days.