YJ motor swap to a newer year!! - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > YJ Wrangler Technical Forum > YJ motor swap to a newer year!!

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineNEW!! HMF 50"-52" light bar mounting brackets!! Year End Clearance Sale! Save 20%

Reply
Unread 05-02-2011, 11:18 PM   #1
Lucanuss
Registered User
1994 YJ Wrangler 
 
Join Date: Apr 2011
Location: loveland, colorado
Posts: 1
YJ motor swap to a newer year!!

Hello!

I am in need of a new 4.0L block for my 94 YJ. I have found a few 98+ Wrangler/Cherokee used blocks that i can get cheap. My question is, Can I put all motor components onto a newer block with out problems. or what year did the 4.0 change to which it would not match up with YJ components?

Lucanuss is offline   Reply With Quote Quick reply to this message
Unread 05-03-2011, 01:05 AM   #2
18Dmedic
Registered User
1989 YJ Wrangler 
 
Join Date: Apr 2011
Location: Sacramento, CA
Posts: 120
I believe 87 to 90 are the same and 91 to 95. I believe that the 97-up are different.
__________________
***USED 15 DAYS*** JKS Adjustable Track Bar for sale $150 plus shipping. PM IF INTERESTED...
***NEW*** TJ Mirror Relocation Brackets $30 plus shipping.
***USED***TJ Flares set of 4 in great shape. $120 plus shipping.
18Dmedic is offline   Reply With Quote Quick reply to this message
Unread 05-03-2011, 01:36 AM   #3
mike_breaker_5
Web Wheeler
 
mike_breaker_5's Avatar
1994 YJ Wrangler 
 
Join Date: Oct 2009
Location: emporium,, pennsylvania
Posts: 2,967
i think the main differences in tj 4.0's and yj 4.0's are the intake manifold and possibly the head. the reason there is no '96 wrangler is partially due to the addition of emissions testing to vehicles.

i know you can put a yj 4.0 into a 97 tj that had a 4.0 in it previously. i don't see why you can't go the other way and slap the newer motor in the yj, but the extent of the parts interchange is uncertain to me. like i said before i know the intake is slightly different due to emissions crap being added in the tj run, simply retain your intake and exhaust manifold. i think after that it's basically the same motor until i think 99 when they changed the head, but i bet the tj 4.0 head will still work if left on the tj motor, the computer won't know the difference.

if you can see the motors side by side out of the vehicle compare everything to see what's different, and just swap it over, i would do a forum search, there has to be someone here that has done it.
__________________
Ratmonkey donation page. all proceeds will go to his family.
http://www.youcaring.com/memorial-fu..._source=widget


it's not much to look at... but it's mine.
5.2lswap, metalcloaks, bedliner, tucked belly, d60's, soon to be nv4500 and d300.
http://www.jeepforum.com/forum/f22/m...r-junk-990191/
mike_breaker_5 is offline   Reply With Quote Quick reply to this message
Unread 05-03-2011, 10:08 AM   #4
Rynfw100
Registered User
1993 YJ Wrangler 
 
Join Date: Feb 2011
Location: Tucson, Arizona
Posts: 473
Quote:
Originally Posted by mike_breaker_5 View Post
i think the main differences in tj 4.0's and yj 4.0's are the intake manifold and possibly the head. the reason there is no '96 wrangler is partially due to the addition of emissions testing to vehicles.

i know you can put a yj 4.0 into a 97 tj that had a 4.0 in it previously. i don't see why you can't go the other way and slap the newer motor in the yj, but the extent of the parts interchange is uncertain to me. like i said before i know the intake is slightly different due to emissions crap being added in the tj run, simply retain your intake and exhaust manifold. i think after that it's basically the same motor until i think 99 when they changed the head, but i bet the tj 4.0 head will still work if left on the tj motor, the computer won't know the difference.

if you can see the motors side by side out of the vehicle compare everything to see what's different, and just swap it over, i would do a forum search, there has to be someone here that has done it.
As the OP said, "BLOCKS" is what he's asking if he can interchange. I believe if you keep the top-end components from your YJ 4.0L and swap them to the TJ 4.0, it should work. If you keep the top end components, you have to switch the ECU, Wiring Harness, and get set up for OBD-II as well. But anyways, do your research, go to the FAQ, I believe I saw a couple of TJ to YJ swap write-ups.
Rynfw100 is offline   Reply With Quote Quick reply to this message
Unread 05-03-2011, 11:07 AM   #5
Alfons
Registered User
1992 YJ Wrangler 
 
Join Date: Jul 2005
Location: Ontario, Canada
Posts: 2,218
If you're asking about fitting an early TJ 4.0 into a YJ wiring and fuel environment, the answer is that you can do that. You need to find a spot for all your sensors, swap your throttle body, fuel rail and injectors. There are a few other odds & ends that you'll need to deal with, but it's all straight forward. You may need to swap the flywheel to match the Crank Sensor needs, but that's not hard to do - if you do need to change the flywheel, I believe the bolts are Torque To Yield (TTY) type & if so, you'll need a new set of bolts.
Alfons is offline   Reply With Quote Quick reply to this message
Reply

Tags
4.0 , i6 , motor , swap , YJ

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.
Note: All free e-mails have been banned due to mis-use. (Yahoo, Gmail, Hotmail, etc.)
Don't have a non-free e-mail address? Click here for a solution: Manual Account Creation
Email Address:

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.


Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.