How do I know which trans I have?

[Zebvance]

Its a 1988 mj that has been converted to 4wd, has a 4.0 in it with a np231j transfer case in it. Also What years where the n231j produced and whats the benefits of it over a np231. I know for sure the back dana 35 is out of a xj, so I'm sure the rest of the drive-train swap was also, I don't know if it is the original trans though, I also have a power shift button and it does work. I know the 4.0 is original, the casting had 88 written on it. the mj came from Canada and has no AC stock and a block warmer and has kph, Celsius, and oil bar pressure gauges also.

[Pete M]

If it's an automatic behind a 4.0, then it's an AW-4. :thumbsup:

[Zebvance]

If it's an automatic behind a 4.0, then it's an AW-4. :thumbsup:

 

 

Haha yea It is a auto! I guess that was a important piece of info to leave out. Is the AW4 a good trans in your opinion? whats the life span of one? rebuild cost? and what kind of power can they handle.

 

If mine is stock is has 100k on it. Sometime I catch it shudder shifting into overdrive or the last gear which every one it is and sometime it will down shift kinda hard into 1st but its every once in a while.

 

I also just got in a flexalite trans cooler with a B&M temp gauge, I ordered them because I got a 100$ gift card to summit from my brother and I didnt know if the shifting slip ups every once in a while were because It was getting warm, the trans fluid looks clean and full also. also I think I wen over kill on the cooler its pretty big, Is there a such thing a over cooling for a trans?

 

Here is a link to the cooler Its dementions are 20 x 7.5 x .750

http://www.summitracing.com/parts/FLX-4120/

 

Here is a picture of the cooler I got

[mvusse]

The 231 J is still being produced. The J designation just means it has an input shaft, output shaft and front output yoke for Jeep vehicles.

 

The 231 C (Chevrolet) is for GM vehicles.

The 231 D (Dodge) is for Chrysler/Mopar vehicles

 

There is also a 231HD (heavy duty) used on some Durangos which supposedly have the wider chain and 6 gear planetary from a 241 in it.

 

On a side note, the Terra 4 low kit also includes a 6 gear planetary. A stock 231 uses a 3 gear planetary which is the same as the 6 with every second gear removed.

[Zebvance]

The 231 J is still being produced. The J designation just means it has an input shaft, output shaft and front output yoke for Jeep vehicles.

 

The 231 C (Chevrolet) is for GM vehicles.

The 231 D (Dodge) is for Chrysler/Mopar vehicles

 

There is also a 231HD (heavy duty) used on some Durangos which supposedly have the wider chain and 6 gear planetary from a 241 in it.

 

On a side note, the Terra 4 low kit also includes a 6 gear planetary. A stock 231 uses a 3 gear planetary which is the same as the 6 with every second gear removed.

 

ok thanks for clearing that up for me. How about the trans cooler. anybody have thoughts about that?

[NotMatt]

Trans cooler will be a good addition to your rig... However, make sure to route it so that you retain the stock "resevoir" in the radiator... It's not there to cool the trans, it's there to heat the fluid up on cold days. Running the trans "too cold" can do just as much damage as "too hot".

[Zebvance]

Trans cooler will be a good addition to your rig... However, make sure to route it so that you retain the stock "resevoir" in the radiator... It's not there to cool the trans, it's there to heat the fluid up on cold days. Running the trans "too cold" can do just as much damage as "too hot".

 

So I should run the trans lines to the radiator how they are then from the radiator to the trans cooler?

[mvusse]

Fluid should run from the transmission to the auxiliary cooler to the radiator cooler back to the transmission.