Which transmission do I have..... TH400????

[76cj7chick]

Hi all,

Anyone out there able to id my tranny? (The tag may be wrong?-- It reads: 75 JR 1128) According to my Haynes Transmission book the tag indicates a TH350... But the pan is definitely a GM Turbo 400 ...

If you know which tranny this is would you also know where the back up light switch should be located? (It is a FLOOR shift automatic)

Thanks for your help!

 

[Old Dog]

It looks like a GM Turbo 400 pan to me.
My TH350 has the reverse lite switch built into the shifter, not sure about the GM Turbo 400 .

 

[76cj7chick]

It looks like a GM Turbo 400 pan to me.
My TH350 has the reverse lite switch built into the shifter, not sure about the GM Turbo 400 .

Oh.. That's good to know.. Maybe mine is built in to the tranny.. Do you know where it's built in on your th350? Perhaps mine is the same?

I do recall the jeep's back up lights illuminated when I first purchased it.. But I just don't know where to install the backup light wiring power and left backup (splices into the right side)...
I will look on the tranny again...

THanks for your help...

 

[Petescj]

There wasnt a TH 350 offered with a bellhousing that would mate to a Jeep engine. If theres no adapter plate between the engine and Transmission its definately a GM Turbo 400 .

Is the floor shifter aftermarket? Mine was column shift , thats whay I ask.

 

[Niedhogg]

Oh.. That's good to know.. Maybe mine is built in to the tranny.. Do you know where it's built in on your th350? Perhaps mine is the same?

I do recall the jeep's back up lights illuminated when I first purchased it.. But I just don't know where to install the backup light wiring power and left backup (splices into the right side)...
I will look on the tranny again...

THanks for your help...

The GM Turbo 400 does not have the back-up light switch in the tranny.. the terminal you have in the side of the tranny is the downshift solonoid which should be wired to a switch that is mounted and activated by the foot throttle under the dash. The reverse lights should be activated by a switch somewhere on the column.

 

[BusaDave9]

Do you have a QuadraTrac Transfer Case ? The rear output is on the passenger side. The GM Turbo 400 always came with the QuadraTrac and vice versa. See if the differential is on the passenger side.
Here is a GM Turbo 400 and a QuadraTrac

I think it matches up with what you are saying. Also this is the automatic Transmission and tcase that came in those years ('76 was the first year the GM Turbo 400 came in CJ's).
BTW that's an excellent Transmission .

 

[OLD 9]

The GM Turbo 400 does not have the back-up light switch in the tranny.. the terminal you have in the side of the tranny is the downshift solonoid which should be wired to a switch that is mounted and activated by the foot throttle under the dash. The reverse lights should be activated by a switch somewhere on the column.

The TH350 uses a cable kickdown pulled by the throttle linkage. As mentioned the 400 uses an electric solonoid usually activated by a switch on the gas pedal. Other than the shape of the case, this is how I tell the diference.

 

[76cj7chick]

There wasnt a TH 350 offered with a bellhousing that would mate to a Jeep engine. If theres no adapter plate between the engine and Transmission its definately a GM Turbo 400 .

Is the floor shifter aftermarket? Mine was column shift , thats whay I ask.

A neighbor said the automatic floor shifter is from a mustang... :0

 

[76cj7chick]

Do you have a QuadraTrac Transfer Case ? The rear output is on the passenger side. The GM Turbo 400 always came with the QuadraTrac and vice versa. See if the differential is on the passenger side.
Here is a GM Turbo 400 and a QuadraTrac

I think it matches up with what you are saying. Also this is the automatic Transmission and tcase that came in those years ('76 was the first year the GM Turbo 400 came in CJ's).
BTW that's an excellent Transmission .

Thanks for the pics...

According to the vin it originally had a AMC 258 i6 / 4.2l 3 speed manual and, I think, the spicer/Dana 20 ...
I will post some pics of the t case and more of the Transmission .

 

[76cj7chick]

Do you have a QuadraTrac Transfer Case ? The rear output is on the passenger side. The GM Turbo 400 always came with the QuadraTrac and vice versa. See if the differential is on the passenger side.
Here is a GM Turbo 400 and a QuadraTrac

I think it matches up with what you are saying. Also this is the automatic Transmission and tcase that came in those years ('76 was the first year the GM Turbo 400 came in CJ's).
BTW that's an excellent Transmission .

Here are some more pics of the Transmission and some Transfer Case .. Hope the pics help..

The Transfer Case has a tag that reads:
300596-53
947652

And it has an embossed code on the rear: C18-15-24 5


Any ideas of what it is?

 

[Petescj]

I can tell you thats a Dana 300 Transfer Case .

 

[BusaDave9]

I can tell you that's a Dana 20 Transfer Case .

Not to be contradictory but the Dana 20 and the Dana 300 look alike. I tell the difference by how the shift levers are attached. The Dana 20 has the shift mechanism attached by a tubular bar on the front of the TCase. This round bar is held on with 2 square head bolts. That's a good tcase. It didn't come in your CJ from the factory like that.

I circled the 2 square head bolts that hold on the tubular bar for the shift mechanism.
It looks like the shift mechanism is a U shaped shift pattern. That shift pattern was in some full sized jeeps and FC Jeeps.

EDIT: here is the non-CJ tcase shift mecanism:

 

[BusaDave9]

You have a '76 CJ.
In '76 if you ordered an automatic you got a GM Turbo 400 with a QuadraTrac TCase.
If you ordered a manual Transmission you got the Dana 20 TCase.
Since you have a GM Turbo 400 and Dana 20 either a PO swapped in a Dana 20 TCase. But that would take an adapter between the TCase and GM Turbo 400 .
OR a PO swapped in a GM Turbo 400 AND Dana 20 Tcase from a FSJ.

EDIT: since you have a TCase with a U shaped shift patter (verify this for me) it looks like a PO took the tranny and TCase from a FSJ.
Mystery solved.

 

[BusaDave9]

The purple circle is around the 4WD switch. CJ's don't have this switch and it looks like yours isn't connected. This switch will turn on an idiot light on the dash of a FSJ to tell you you are in 4WD.

 

[BusaDave9]

Here is another GM Turbo 400 with a Dana 20 .
This Dana 20 also has the shift mechanism with the U shift pattern.
All Dana 20s have the shift mechanism supported with a tubular bar out the front of the TCase held on with square head bolts.

 

[Petescj]

I can tell you that's a Dana 20 Transfer Case .

Ouch! good catch Dave. I even looked downstairs at mine for reference and thought it was a 300. Shouldve looked at the front view as well.

 

[76cj7chick]

I can tell you that's a Dana 20 Transfer Case .

Not to be contradictory but the Dana 20 and the Dana 300 look alike. I tell the difference by how the shift levers are attached. The Dana 20 has the shift mechanism attached by a tubular bar on the front of the TCase. This round bar is held on with 2 square head bolts. That's a good tcase. It didn't come in your CJ from the factory like that.

I circled the 2 square head bolts that hold on the tubular bar for the shift mechanism.
It looks like the shift mechanism is a U shaped shift pattern. That shift pattern was in some full sized jeeps and FC Jeeps.

EDIT: here is the non-CJ tcase shift mecanism:

Thanks for the help...

The Transfer Case looks like it may have been a double stick/lever... Would that still be a Dana 20 ? Mine looks like the one the pic you posted but the larger tube like "pipe" is not there.. Only a hole and what looks to me like threads... Is that part important? If yes, would you know what its called and what it does?
Thanks bunches for your help!

 

[76cj7chick]

You have a '76 CJ.
In '76 if you ordered an automatic you got a GM Turbo 400 with a QuadraTrac TCase.
If you ordered a manual Transmission you got the Dana 20 TCase.
Since you have a GM Turbo 400 and Dana 20 either a PO swapped in a Dana 20 TCase. But that would take an adapter between the TCase and GM Turbo 400 .
OR a PO swapped in a GM Turbo 400 AND Dana 20 Tcase from a FSJ.

EDIT: since you have a TCase with a U shaped shift patter (verify this for me) it looks like a PO took the tranny and TCase from a FSJ.
Mystery solved.

BusaDave9, That "EDIT: since you have a TCase with a U shaped shift patter (verify this for me) it looks like a PO took the tranny and TCase from a FSJ.
Mystery solved." sounds/looks right to me...

Now, I just need to figure out which wires attach to the Transfer Case switch on top... (emergency/4wd light on speedo... if not... Any ideas?


Also, anyone know where I can find a Transfer Case floor shift bezel? I know there are knobs but I'd rather have a illuminated floor bezel to show what gear I am in...

Thanks, and hope you all had a great New Year!!!

 

[76cj7chick]

Here is another GM Turbo 400 with a Dana 20 .
This Dana 20 also has the shift mechanism with the U shift pattern.
All Dana 20s have the shift mechanism supported with a tubular bar out the front of the TCase held on with square head bolts.

Oh, another thing...
So, my tcase shift pattern is 2H 4H N 4L ?

Anyone know why my tcase shifter is soooo short? There are some threads but it's short... Is it normal?


Thanks again BusaDave9..

 

[BusaDave9]

Also, anyone know where I can find a Transfer Case floor shift bezel? I know there are knobs but I'd rather have a illuminated floor bezel to show what gear I am in...

that shift mechanism came out of a full sized jeep. Check out this link: Jeep Dana 20 Transfercase rebuild Offroaders.com 4x4 off-road trail reports, tech articles