Transmission shifting weird

[MoparDan]

The transmission seems to be shifting strange so I drove a few different ways: normal driving: I felt it shift three times: at about 20 mph, then about 30 mph, then about 50 mph, i thought this was a three speed transmission so why would it shift three times? Next I hit the gas pedal harder the usual: shifted twice first at about 35 mph then at about 55 mph. Next I got on the highway a just floored it to about 80 mph, and there was only one shift at about 50 mph and it was a pretty rough shift. I know almost nothing about transmissions but this doesn't seem right at all

 

[Aspen500]

I think the extra "shift" you're feeling is the torque converter clutch engaging. It will cause an rpm drop and can feel like a gear shift to some extent. Usually 200-300 rpm roughly. That's my guess anyways, going by the description you gave.

 

[MoparDan]

I should add car is a totally stock '85 Gran Fury with transmission code DGA, and yes I did check the fluid level and its fine, I did have the fluid and filter changed but that was a few years ago, it should also be noted that this was in a flood during the last hurricane and both the engine and differential had filled with water and had to be drained, the garage said the transmission fluid looked fine

 

[MoparDan]

I think the extra "shift" you're feeling is the torque converter clutch engaging. It will cause an rpm drop and can feel like a gear shift to some extent. Usually 200-300 rpm roughly. That's my guess anyways, going by the description you gave.

That makes sense, it felt like three shifts so maybe one time its was the torque converter. I never really paid attention to when it was shifting until yesterday, I really know nothing about transmissions except how to check the fluid level

 

[BudW]

It is the TCC (Torque Converter Clutch) engagement you are feeling - so it is normal.
Sometimes you can feel it shift four times if driving up a small grade at low throttle position (2nd, 2nd w/TCC, 3rd and 3rd w/TCC).

Note: you are getting about 10% better fuel mileage anytime the TCC is engaged – because there is normally 10-15% slippage inside of a torque converter when cruising.
The TCC turns off when power is applied, so it can use the torque multiplication the converter provides. When load is removed, the TCC re-applies


Right now, I’m not far from building either an A727 or A518 for my Fifth Ave. If I was going to race it full time, a non-lockup might be the way to go (fewer things to break). Sense my car will be 95% (or more) street driven, I want a lockup clutch for it, for the increased fuel mileage.

My ’77 wagon does not have lockup – and I miss it.
Chrysler came out with it mid-year ’78 – so a few big blocks came with lockup.
BudW