Jeep 4.0 in 81 cj

brokejeep

Registered User
Location
Clearfield, Utah
I am purchasing a 2004 4.0 for my jeep cj. the previous owner cut the harness while removing it from his jeep. While searching I found that HESCO produces a kit to do a direct swap but it is $1800. Do I need to buy the kit or can I make my own? How hard is the conversion? I was hopeing to keep my T-5 and swap in the engine. Anybody who has been through this before, I would appreciate some advice before I get started.
 

bobdog

4x4 Addict!
Location
Sandy
My advice would be to replace the T5 with a better tranny. If you have not already bought the 4.0 I would concider a V8 it would not be any harder to swap.
 

DaveB

Long Jeep Fan
Location
Holladay, Utah
I put a 99 TJ 4.0 into my 84 cj8 and it works very well. There are times I wish I had a v8 (except at the gas pump). They are great for crawling on rocks but if you like to mud bog or do lots of sand the v8 would be better. I used the wiring harness and fuel rail from a 93 cherokee. If you want to stop by some night I can show you what has to be done. There is also a forum on cjoffroad.com that is all about the swap.
 

brokejeep

Registered User
Location
Clearfield, Utah
I have already considered the V8 conversion and I really don't need the extra cost of blowing through axles and tranny's and every thing else. If I ever swap to a v8 I will swap the entire drive train. Dave B, I have seen your jeep when my brother bought the dash from you. The engine I am going with is a 2004 will that make it different from yours? I would appreciate it if you would let me come by and see your work again.
 

DaveB

Long Jeep Fan
Location
Holladay, Utah
I have already considered the V8 conversion and I really don't need the extra cost of blowing through axles and tranny's and every thing else. If I ever swap to a v8 I will swap the entire drive train. Dave B, I have seen your jeep when my brother bought the dash from you. The engine I am going with is a 2004 will that make it different from yours? I would appreciate it if you would let me come by and see your work again.

The 2004 does have the different ignition system but I believe you can put an older system on it which (will be easier to do than the newer wiring). I just put a 2001 motor in my 96 zj, it had the newer ignition system and I swapped the older distributor and wiring onto it. There are some differences in 4.0 motors with the motor mounts and accessory mounts on some of the newer motors, especially if it came from a Grand Cherokee. If you have the right engine you can re-use the motor mounts from your old 4.2 straight six, unless you have the four cylinder motor. You can come by and I'll show you what I did on my cj. If you don't remember where I live send me a PM.
 
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brokejeep

Registered User
Location
Clearfield, Utah
I just picked up my engine. I know there is a code on the side that will tell me what year the engine is from. Does any one know which code it is. I believe this engine is older than the seller said.
 

DaveB

Long Jeep Fan
Location
Holladay, Utah
On the newer ones there is usually a sticker on the front of the valve cover that tells you what it is from. What did he have it in ? or was it out already ?
 

brokejeep

Registered User
Location
Clearfield, Utah
the engine is already out and the seller got it from a friend who owned a shop before he was sent to prison. The seller cleaned out the shop for his friend and the engine I got was going in a customers jeep. The customer took his business somewhere else and he was stuck with the engine. I took a risk, but I got the engine trans and transfer case for $140
 

brokejeep

Registered User
Location
Clearfield, Utah
Is there a way to tell what year my motor is without the sticker on the valve cover. I have the partial vin that is stamped in the passenger side. Will that help me at all. I need to find out what year of wiring harness I need to get, also I am missing the lower pully. If anyone can help me that would be great.
 
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