Transmissions that mount up to a 4.0 I6

[Aidenmoreno3]

Good morning to all! I was curious as to which transmissions will bolt up to the Jeep 4.0. Right now I believe there is a Chevy trans connected to the vortex swap the previous owner did (haven’t ripped into my MJ for a swap yet). Appreciate the help this far guys! Love the website

 

 

also quick side note I was told I need to do 10 replies or posts and I was just curious if someone who is a long time user of this forum could clarify that for me 

[Money_Pits]

20 hours ago, Aidenmoreno3 said:

Good morning to all! I was curious as to which transmissions will bolt up to the Jeep 4.0. Right now I believe there is a Chevy trans connected to the vortex swap the previous owner did (haven’t ripped into my MJ for a swap yet). Appreciate the help this far guys! Love the website

 

 

also quick side note I was told I need to do 10 replies or posts and I was just curious if someone who is a long time user of this forum could clarify that for me 

 

 

Ten posts unlocks classifieds. Parts are getting hard to find, along with knowledge on these trucks, so the restriction is meant to ensure that new members help contribute to the knowledge base (even if it's just asking a question and posting a build thread) and not just use this site to farm parts.

 

As for tranny, do you mean stock or with adapters? Cause with an adapter nearly anything will bolt up.

[derf]

Here's a somewhat incomplete list. 

 

It's important to note that many of these transmissions (mostly the automatics but at least one manual) had an integrated AMC specific bellhousing that will bolt up to the 4.0 without adapters.  If you get one with a different bellhousing, it won't bolt up.  The manuals mostly have removable bellhousings that are AMC specific As long as you can find the right bellhousing, any donor should bolt up.

 

Stock XJ:

• Aisin AW4 - 4 speed automatic (Best option for "easy" bolt up to a 4.0 in an XJ)
• Peugeot BA10/5 - 5 speed manual (weak transmission, not worth the effort to swap in)
• Aisin AX15 - 5 speed manual (good solid trans, best overall candidate for a manual transmission swap)
• NVG3550 - 5 speed manual (good trans that replaced the AX15 late in the XJ production)

 

TJ and YJ (Wrangler) with the 4.0 (4 cylinder transmissions are different and not good candidates behind a 4.0):

• Chrysler 32RE/32RH - 3 speed automatic "E" is electronically controlled, "H" is hydraulic (no need for computers)
• Chrysler 42RLE - 4 speed automatic.  Not a great transmission and the computer will make it difficult to swap in.
• Peugeot BA10/5 - same piece of junk as the XJ.
• Aisin AX15 - same as XJ
• NVG3550 - same as XJ
• NSG370 - 6 speed manual trans in the last 2 or 3 years.  Weaker than the AX15 and NVG3550.  Not the best swap candidate.

 

ZJ (Grand Cherokee) with the 4.0 (V8 has different bellhousing):

• Chrysler 42RE - not the same as the TJ.  The computer makes it difficult to swap.
• AX15 - same as XJ, but very rare.

 

Going back further to the 258 (pre-4.0) version of the engine, you get a bunch of options from early YJs, CJs, Full Size Jeeps and AMC cars.  All of the automatics listed below will be fully hydraulic (i.e. no computer).  Most of these do not have overdrive.  Most of these will be difficult to swap into an XJ.

• Borg Warner T5 (AMC cars and CJs) - light duty 5 speed manual with overdrive.  (not the best option behind a 4.0)
• Chrysler 904 (became the 30RH), 998/999 (became the 32RH) - medium duty 3 speed automatics (bigger number is stronger)
• Chrysler 727 (mostly in full size jeeps 1980-1991) - heavy duty 3 speed automatic
• GM TH400 (mostly in Jeep CJ and full size Jeeps) - heavy duty 3 speed automatic
• Tremec T176/177/178 - medium duty 4 speed manual in CJs and full size Jeeps
• Tremec T150 - medium duty 3 speed manual
• Warner T14 - medium duty 3 speed manual
• Warmer T15 - medium duty 3 speed manual
• Warner T18 - medium duty close ratio 4 speed manual
• Warner T18a - medium duty wide ratio (i.e. first gear is a granny low) 4 speed manual.

 

For transmissions that can be adapted to the 4.0, see http://www.novak-adapt.com/ and https://www.advanceadapters.com/

[omega_rugal]

AW4 if you want automatic, AX15 if you want manual are the best options

 

also, you didn´t mention how you plan to use: on road, off road, light towing, heavy towing...

 

for light duty on road even a BA10/5 will do, if you happend to find one that is not shot and cheap...a Chrysler 32RE/32RH with the right rear axle ratio will work fine in the city but it won´t be fast enough in the highway, also your mileage will suck, avoid the 42RE, it has a lot of issues, the older 32RE/32RH is actually stronger and more reliable

 

all the others are too old, have very wide ratios and no overdrive, heavier, etc... useful only for heady duty tasks or extreme offroading