46rh trans behind 3gen Hemi

[dickdale]

I have a 46RH (from 1992) behind my 6.4 Hemi engine (from 2014). The transmission doesn't seem to shift right. The fluid level is ok. Rear end has 3.91 ratio and the convertor is stock from a b250. The engine is also stock.

When I start driving it shifts fast to second gear. To fast if you ask me. It will shift to third gear. Besides it shifting fast the OD en LU doesn't work like they should.

I've connected two switches to engage the OD and LU. LU works fine, OD doesn't work fine. Only after taking the foot of the throttle it engages and then it wouldn't go out of OD when decelarating.

An other problem is when the trans is in D and I want to make a full stop, it looks like the engine wants to stall. When putting it in D of second gear the engine will idle like normal. After going to a full stop and putting the trans in D again it will shift but again very fast.

What can cause these problems?

 

[69Bee]

Are you using an aftermarket controller for the transmission or the pressure switch setup? With the aftermarket controller, it needs to be calibrated with the speedo to work. My friend made this easier with an electronic speedo. The mechanical vac/pressure switch setup needs to be calibrated also.

 

[dickdale]

I'm using 2 PATC vacuum switches

 

[Greg Ducato]

Sounds like you need to tighten up the TV cable adjustment, a cable that is too loose will cause soft early shifts and no overdrive.

 

[dickdale]

With Throttle Valve cable you mean the kickdown cable?

I’ve got a drive by wire throttle body and used the old gaspedal assembly under the dbw gaspedal that came with the mopar harness kit to control the kickdown linkage on the trans.

 

[Greg Ducato]

The cable also delivers kickdown but its main purpose is control line pressure rise in the trans according to throttle demand

 

[dickdale]

Would it be possible to do a test drive without the kickdown cable hooked up and not floor it but drive it slow just to see if the ODis working?

 

[Cranky]

Would it be possible to do a test drive without the kickdown cable hooked up and not floor it but drive it slow just to see if the ODis working?

Not sure about that but the 92 trans is hydraulically controlled and not electronically but I'm thinking you know that. The OD is electronically controlled so I'm thinking you can do what you are asking. Most people I know have a separate switch for the OD but they have to manually flip the switch to shut if off when they come to a stop. IIRC, same thing for the lockup converter. If it stays in lock mode, it'll kill the engine when you stop.

 

[Greg Ducato]

The trans has to have sufficient line pressure for overdrive to work, you must hook up and properly adjust the cable to get correct shift timing and overdrive, no short cuts or exceptions.

 

[dickdale]

The OD and LU are now controlled by a simple on/off switch.

At what point does the kickdown needs to function in combination with the pedal travel? Halfway, 20% pedal travel, etc?

 

[Greg Ducato]

At wide open throttle the trans lever should be all the way against its stop, if shifts are too late at that point you can adjust it looser till you reach the results you are looking for.

 

[dickdale]

I’ve got it set like that already. Gas pedal all the way the floor is KD lever all the way to the back on trans. It has little bit of play. Guess I will try and play with it.

 

[dickdale]

Here are some pictures of my assembly. I found out that when the pedal is to the metal the KD lever isn’t fully engaged. So I have to do some tweaking. Perhaps I also have to delete the wheel so I have more travel before hitting the KD when going full throttle.

 

[Greg Ducato]

Your design to use both cable and DBW is very clever, that was a good idea and one I'm sure you can work out.

 

[dickdale]

Thanks! Now to make it work correctly with a trans that functions like it should.

 

[Greg Ducato]

Its all about geometry