I am not a Jeep expert (nor even owned one). I can say I have ridden one a couple of times.
I believe the 4.2L Jeep engine is AMC design (using parts from GM, Ford, Chrysler, etc.). I’ve heard the 4.0L is more of a Chrysler design (not piecemeal like the 3.8L is) – but not confirmed.
I hadn’t heard the /6 and 4.0L are related – but I’ve seen both bare blocks together and all kinds of light bulbs went off in my head.
I still think the 4.0L (245 ci.) Jeep engine looks awful lot like the 245 ci Aussie Mope engine, shown in first two postings. It might be camera lighting and/or my dirty glasses, if I’m incorrect (which I might be).
Now I do know the /6 uses the same timing chain and rear main seal as the big block (and possibly the lifters - but nothing else).
BudW
I believe the 4.2L Jeep engine is AMC design (using parts from GM, Ford, Chrysler, etc.). I’ve heard the 4.0L is more of a Chrysler design (not piecemeal like the 3.8L is) – but not confirmed.
I hadn’t heard the /6 and 4.0L are related – but I’ve seen both bare blocks together and all kinds of light bulbs went off in my head.
I still think the 4.0L (245 ci.) Jeep engine looks awful lot like the 245 ci Aussie Mope engine, shown in first two postings. It might be camera lighting and/or my dirty glasses, if I’m incorrect (which I might be).
Now I do know the /6 uses the same timing chain and rear main seal as the big block (and possibly the lifters - but nothing else).
BudW
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