out of curiosity xj to yj question - JeepForum.com
 
LinkBack Thread Tools
post #1 of 9 Old 01-16-2013, 08:27 AM Thread Starter
wanabejeeper
Registered User
1987 YJ Wrangler 
 
Join Date: Aug 2009
Location: NJ
Posts: 549
out of curiosity xj to yj question

If was to do an xj to yj 4.0mpfi head swap using the entire computer and wiring setup and since I have a tf909 could I also take the tf999(actually AW4 as noted by 94chb below) and take advantage of the 4 speed or lock up converter (not sure which it has)? I intend to replace the NP207 that I have with a 231 with an SYE when I do a lift in the spring if I have driveline issues. Would it make more sense to wait and use the 231 from the xj?


87 YJ The Original!

Quote:
Originally Posted by Anticanman View Post
It goes in that barrel you wheel out to the street once a week.

My build thread http://www.jeepforum.com/forum/f12/n...thread-867043/
wanabejeeper is offline  
Sponsored Links
Advertisement
 
post #2 of 9 Old 01-16-2013, 09:12 AM
94chb
Registered User
1989 YJ Wrangler 
 
Join Date: Dec 2009
Location: Whitwell
Posts: 1,936
xj doesnt have a tf999 but a AW4 , my 89 yj came with a tf999 but when i went FI i discovered i couldnt use my trans because there is no CPS or even a spot for one. i found a aftermarket kit that puts a CPS on the front of the crank but it was expensive. so i just went ahead and went to the ax15
94chb is offline  
post #3 of 9 Old 01-17-2013, 08:23 AM Thread Starter
wanabejeeper
Registered User
1987 YJ Wrangler 
 
Join Date: Aug 2009
Location: NJ
Posts: 549
bump any other suggestions.... I'd like to get away from the 3peed auto to a 4 speed auto. Is it possible the way I'm thinking?

87 YJ The Original!

Quote:
Originally Posted by Anticanman View Post
It goes in that barrel you wheel out to the street once a week.

My build thread http://www.jeepforum.com/forum/f12/n...thread-867043/
wanabejeeper is offline  
post #4 of 9 Old 01-17-2013, 08:29 AM
dillonjm
Registered User
2013 WK 
 
Join Date: Jun 2003
Location: Wichita Falls, TX
Posts: 4,167
You can run an AW4 in a YJ, I do.

Sounds like you're wanting to just swap the whole shebang over which isn't a bad idea, especially if you can get all the wiring/computer/TCM. It will save you some wiring for the tranny if you decide to use the AW4.

Or am I misunderstanding your question?

13 GC Overland - 5.7, stock
dillonjm is offline  
post #5 of 9 Old 01-17-2013, 09:13 AM Thread Starter
wanabejeeper
Registered User
1987 YJ Wrangler 
 
Join Date: Aug 2009
Location: NJ
Posts: 549
Nope you have it right. I have a freshly rebuilt 4.2 but the older 909 and 207. My thinking is if I take the 4.0 mpfi and associated computer wiring etc, why not take the 4 speed tranny and the 231. I'm just wondering what hoops I'll have to jump through as par tof the install.

I've planned to do the MPFI upgrade from the very beginning and have learned about the SYE as part of the lift. The SYE is only available for the 231 that I can find. I plan on ditching the shackle lift that is on it and going to OME or Black diamond 2.5 to 3"" springs 1" booms and an SYE assuming the SYE is necessary. So that lead me to wonder if I'm getting the MPFI from the cherokee and the 231 why just not put the whole shebang in and getting a 4 speed while Im at it.

The big question is above and beyond the mpfi. What mechanical changes/ adaptors/ linkage changes will I need to overcome?

87 YJ The Original!

Quote:
Originally Posted by Anticanman View Post
It goes in that barrel you wheel out to the street once a week.

My build thread http://www.jeepforum.com/forum/f12/n...thread-867043/
wanabejeeper is offline  
post #6 of 9 Old 01-17-2013, 09:40 AM
dillonjm
Registered User
2013 WK 
 
Join Date: Jun 2003
Location: Wichita Falls, TX
Posts: 4,167
Pretty much everything will be new.

You'll need motor mounts, tranny mount, etc. You can fab a transmission mount that uses the yj style rubber isolator and mates to your current skid plate very easily- it just requires some 1/4" flat bar. You can use the factory xj transmission shifter and cable, it actually mounts to the yj tranny pan very nicely. You'll have to fab up a t-case shifter.

You'll also want to clock the tcase up a little, the xj clocking hangs it down farther than you'd want in a YJ. This just requires drilling new holes, very easy as well.

There is lots of info on putting an aw4 into a YJ on the net. Any of those write ups address the linkage/mounting issues. The engine stuff will be the same as any swap. You'll need to burn in some motor mounts and address plumbing and wiring.

Jerrod

13 GC Overland - 5.7, stock
dillonjm is offline  
post #7 of 9 Old 01-17-2013, 09:48 AM Thread Starter
wanabejeeper
Registered User
1987 YJ Wrangler 
 
Join Date: Aug 2009
Location: NJ
Posts: 549
The big question then is can I keep the 4.2 block?

87 YJ The Original!

Quote:
Originally Posted by Anticanman View Post
It goes in that barrel you wheel out to the street once a week.

My build thread http://www.jeepforum.com/forum/f12/n...thread-867043/
wanabejeeper is offline  
post #8 of 9 Old 01-17-2013, 10:06 AM
94chb
Registered User
1989 YJ Wrangler 
 
Join Date: Dec 2009
Location: Whitwell
Posts: 1,936
my was the 4.2 and 909, im now 4.0 from newer jeep and mpfi and ax15, also lifted 4.5 and no SYE also my lift is up for sale cheap. im now going SOA and d44 front and rear and stretching around 10 in.


yes you can keep your 4.2 block if you want to, everything bolts up the same as 4.0 block
94chb is offline  
post #9 of 9 Old 01-17-2013, 10:48 AM
YJ4LIFE
Registered User
1989 YJ Wrangler 
 
Join Date: Dec 2011
Posts: 827
Quote:
Originally Posted by wanabejeeper View Post
The big question then is can I keep the 4.2 block?
there was a thread last week about it being externally balanced and having issues with an aw4.

'89 YJ, 4.2L, ax-15, B&M shifter, 1" BL, TJ flares, '99 intake, '91 EFI, 5.0L explorer injectors, GenRight tank & stretch, 35" ProComp Xtreme muds, 52" chevy springs rear, 44044 Ranchos front.....
YJ4LIFE is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome