• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Input needed on trans swap ideas

9

94XJfool

NAXJA Forum User
Location
Quincy, MA
MY AW4 is starting it slow death. A month ago when I put my lift on and 33 tires it has started slipping getting worse at a some what alarming rate. i am hoping to get another year or so out of if but I am looking into some options for swaps. I am looking into swaping an in an AX15, NV3550, NV4500, another aw4, Or, now this is where my big question comes in, a 545RFE. Has anybody ever tried putting in the 545RFE? I imagine that it is far more work than it is worth but i am the curious type.
 
You don't want a 545RFE, I've seen so many WJs with them blown up.

The 545RFE natively has a smallblock mopar (3.9 V6, 5.2 V8, 5.9 V8, 3.7 V6, 4.7 V6, 2.8 CRD, 5.7 Hemi V8) bellhousing pattern so you're going to need to do some interesting things to mount it to the back of a 4.0 anyways.

IIRC you can put an NP435 or some other similar Ford 4-speed with a granny gear behind a 4.0 with a factory bellhousing from something or other and a little machine work to make it match up, plus mounting the CPS. I forget the specifics.

What year XJ? 97 and later are a little harder to fool the electronics into not flipping out about the AW4 going missing, 98 and later are slightly harder than 97, all can be solved using either trickery, trickery plus a 97 trans controller module, or reflashing the ECU to a manual firmware image.
 
I have a 96 so fooling the computer shouldn't be too hard. I like to say that the 96 has the dumb down OBD2. I have the 545rfe in my WJ and it is a great automatic, IMHO. The aw4 isn't exactly a stellar preformer either.
 
Yeah I'm not sure where the 545RFE hatred comes from. My father's friend has over 150k on a stock one in his 1500 behind a 5.7 hemi that tows his car.

But for an XJ, I don't see the gain with switching to a 545RFE. What are you looking to gain? If it's just gearing, I'd look into a 231/300 or 231/231 doubler.
 
Currently I am running HP30 up front and a c8.25 rear with plans to build and swap in an 8.8 by next year. Currently I am sitting in stock gears 3.55, and plan to upgrade to 4.56. I far prefer the 1st gear ratios of the ax15 and nv3550/4500 over the aw4. Also I hate the idea of replacing my aw4 when it dies with a used aw4 that I don't know the history of. Based in the pattern of damaged/warn out parts and the rusted in trailer hitch it used to have I know that one of the previous owners used this Xj as a trailering rig.
 
I have blown up two AW4s and I still think it's not a bad auto, they're pretty durable, you have to really hammer on them to break anything.

Colin, my hate for the 545RFE is because a friend's parents have had 3 of them crap out on them, some under dealer warranty, and bradley's is slipping now I think. He bugged me a while ago to see what kind of man trans would fit a WJ because he wasn't sure if it was going to last or something. And I've heard from others that this isn't unusual. That plus the fact that it won't natively fit the 4.0 and has an integral bellhousing makes it a lot of work to swap in behind a 4.0 for uncertain gain.

The crummier first gearing on the AW4 is somewhat made up for by the fact that it has a torque converter.
 
Ok then What is the best way to modify the AW4 to make it better. I honestly cant stand the fact that I have little control over What Gear I am in. If I pop it into 1-2 it goes into 1st gear and stays there. It will not shift into 2nd gear which is very annoying wheeling it. 2nd gear is the problem right now it slips kinda bad randomly. also to shortXJdoug. what is your avatar pic? i can see that it is the roof of an XJ? I have been trying to figure it out for about 10 minuets now
 
It will go into 2nd, but it won't do it till around 4500rpm. On a 96, you can add a non momentary SPDT switch easily that will force to first gear, force to second gear, or leave the factory trans controller in control, it's just one wire that needs to be modified.
 
Yup. Here's everything I know about the AW4, I updated this a few weeks ago with input from others who researched stuff past the point where I left off: http://www.naxja.org/forum/showthread.php?t=1053970

So basically you take an on-off-on non-momentary SPDT toggle switch, cut the wire to the #2 shift solenoid, wire the solenoid end to the center/common pin on the switch. Wire one of the side pins to the other end of the cut wire (which leads to the TCU.) Wire the third pin to +12V.

Center = nothing is connected, solenoid 2 is OFF, so you're forced into first gear.
Switch selecting +12V = solenoid 2 is ON, so you're forced into second gear.
Switch selecting TCU output = solenoid 2 functions as it normally would using factory TCU.

This obviously will make things screwy if you try to use anything aside from the TCU setting when the shifter is in 3 or D, but it shouldn't hurt anything really.
 
To me, it sounds like you're leaning towards a manual. Unless you have cash burning a hole in your pocket, I'd recommend you drop in one that will already fit. Although a NV3550 would be great, they may be a little hard to find. Next and more available is the AX-15. Not as robust, but surely not a bad trans. It's also made by Aisin-Warner like the AW4.

Lastly, if you're okay with an auto, why not just rebuild the AW4 yourself, or get it rebuilt by a shop. If you pull the trans yourself, it'll probably save you some $.

I think the AW4 is a pretty tough and trouble free trans. I have 215K on mine. A little slow to shift when cold, but no slipping yet.

Good luck.
 
Yes I would like a standard, thing is, I have never wheeled in one. Everybody tells me it's more trouble than its worth. I am considering rebuilding it myself because, as options to, it's is the cheapest and I know what I am putting back into the jeep.
 
Two feet, two pedals, less torque stress applied to the drivetrain, AW4 is a strong tranny. A few years ago, I swapped a JY low mile AW4 into my 89 XJ to replace the BA10 5 speed and wouldn't go back to a manual for a wheeler.
 
Rory at RADesigns makes some killer shifters for the AW4. I ran one in a 94 XJ and I loved it. It was the single best modification I made to that Jeep.
 
swapped out a aw4 for a ax15 in my 95, prob the favorite thing i did to this rig besides the atlas, with that being said aw4's are great trans and are basicly bomb proof
 
there are plenty of write ups threads and info threads on shift controlers for the AW4 on here. Do a quick search and you will find plenty of info to be able to control the AW4 like a manual...
 
You must log in or register to reply here.

Similar threads

L
Manual to Auto transmission swap
Replies
9
Views
201
lvcanyoneer1
L
M
NP 231 input shaft
Replies
3
Views
2K
RCP Phx
R
B
2000 4x4 sport with 4.0 auto trans issues looking for help.
Replies
4
Views
1K
lawsoncl
L
Anak
Fuel Pump Options for '87-'93
Replies
1
Views
1K
tjmotter
tjmotter
R
AW4 trans pump seals
Replies
4
Views
1K
TheXJDrew
TheXJDrew
Back
Top