4.0 AND 4.0 ho engine blocks the sAme??

[gbaronetXCR]

I have a 90 4.0 and picking up a 94 ,4.0 HO for parts. The guy will toss in the old engine core if I want it with the rest of the Jeep.
Can I build up this bottom end for mine?

 

[Dr. Dyno]

Yes. The '90 and '94 engine blocks are basically the same.

 

[FUNKYTEE5]

I have a 90 4.0 and picking up a 94 ,4.0 HO for parts. The guy will toss in the old engine core if I want it with the rest of the Jeep.
Can I build up this bottom end for mine?

There is a few minor differences. I just ended up with a crack in my 93 4.0 block in #3 with 149k. So while at the junk yard I had to assess the differences and I ended up with a Renix block. Renix blocks don't usually have the ignition coil mount bosses that the HO blocks have (early 90's may). The main bearings may have the tabs in different places than the HO. The Renix block also looks far more ridgid than the HO block, the deck has less water ports and all of the castings look thicker within. DC probably began to skimp on iron to save $$ when the HO blocks began production. Overall they will bolt up and swap with no issues, but make sure to check the main bearing tab location.

FUNKYTEE5

 

[gbaronetXCR]

excellant...! Looks like a bad #2 main bearing but the rest is good..
Thanks