C4 Hard Shift into Reverse

[Shulaps]

I have a ’74 with a C4 auto, 302. Since I have owned it, it has always shifted hard into reverse. RPM is around 850. Changed the fluid and adjusted the bands and no significant change? I would almost say it bangs into reverse, are they normally like this or is there something else I can do to soften the shift? I am 3 full turns out on the band adjustment.

Bill

 

[Broncobowsher]

Lower the idle. Should be idling closer to 650.

 

[gray gables]

had the same thing happen to me when my tranny was re-built. I brought it back to him and said what's up with this. Long story short he changed out my torque converter and it now shifts smooth into reverse.

 

[Shulaps]

I will try and drop the idle down a bit, I thought I had it as low as I could but I rebuilt the carb on the weekend so I may be able to get it down a bit more.

Bill

 

[blubuckaroo]

I will try and drop the idle down a bit, I thought I had it as low as I could but I rebuilt the carb on the weekend so I may be able to get it down a bit more.

Bill

That's 650 RPM while in gear. If you have vacuum leaks, the out-of-gear idle will be a lot higher. No matter, it's still gonna clunk a bit. It's the nature of the car.

 

[Broncobowsher]

A couple more items that can lead to large RPM drops going into gear.
Vacuum advance connected to manifold vacuum instead of ported vacuum.
Too much initial timing.

 

[Shulaps]

I screwed in the idled jets a bit. They are at about 2 out from seated and I am getting a lower idle and it seems to be shifting better. I am at 650 while in park now. Sounds a bit lumpy now (sounds a little like a cam) but it seems to rev up fine and returns to idle well. I had them out 2.5 to 2.75 and I couldn't get the idle down lower than 850 before.

Bill

 

[BroncoBoom]

Correct me if im wrong but if your rear end is wearing out it could be creating excessive play when shifting creating a rough shift.
How old is your rear end ?

 

[Shulaps]

I am thinking the rear end is about 40 years old

With the lower idle it does shift better. Trying to research adjusting the carb (2100) as it seems rough at an idle now at 2 turns out but that is the only way I seem to get the idle down to 650. It idles smoother when 2.5 out but I can't get the Rpm below 850?

Bill

 

[Shulaps]

Anyone have a link or pictures to the proper vacuum line routing. I noticed my dashpot isn't hooked up and I am thinking that is why my truck keeps stalling while 4x4ing. Also may have something to do with the idle adjusting.

Bill

 

[YNOTBOB2007]

There is a fast idle adjustment on the passenger side of the carb that may be out of adjustment. Get that one lowered, then fine tune with the street idle adjustment on the drivers side.