Upgrade Your Jeep from a 4.0L to 4.6L Crate Motor by Chad Golen September 9, 2025 0 The 4.0L inline-six engine has long been recognized as one of the most reliable engines on the market. It was the stock engine in most Jeep CJ, Wrangler, and Cherokee models between 1971 and 2006. However, despite its reliability, it was notoriously underpowered. Whether you have an old Jeep that you need an engine for, … Read More