Can I replace 4.7 With a 4.0 They are both 1999 jeep Grand Cherokee
Anything is possible, just understand that the list modifications and changes would be long, including the entire computer management system, It would be far more cost effective to rebuild the 4.7 V8 to your exact specifications, making it more durable and outperform the 6 cyl 4.0.
Thanks for the Advice, Problem is I do not have the original block that came out.
You're most welcome. Grand Cherokees with 4.7L engines can be found at local Pick-a-part / Pull-a-part type wrecking yards, and an entire engine can be had for UNDER $300 with warranty, probably slightly more at a regular salvage yard. Also, you can check craigslist etc I have seen them for sale there too by someone who totaled their Jeep and only had liability so they were parting it out.
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