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Wrangler 4.0 the same?

ehall

NAXJA Member
NAXJA Member
My '91 beater needs a new engine pretty soon. I'd really like to drop in a 4.0 from a '99 so that I get the better intake, and it looks like using my old computer, sensors and senders will be pretty straightforward (might have to drill and tap for a temperature sender but otherwise it's drop-in).

Looking through car-part.com I've found a bunch of '99 4.0 engines, but the ones with low mileage are all from Wranglers. I guess they got rolled a lot more than the grocery getters... :)

I'm sure these things had the same block and heads as the XJ setup, but what about other stuff like intake, exhaust, tranny hookup, etc. Are they 100% identical?

Thanks
 
Double check I believe you may have to upgrade the wiring from a 96 or so. Has ditrubator less (coils on spark plugs) I lknow in the 96+ in the XJ the engine set up changed so think along the same lines. Not to sure on the details but I wanna say you can use it but with some mods. A 4.0 is a 4.0 block wise. Differnce in heads being ported out for better intake, but it's how it's setup to run,

Someone chime in if talking BS.
 
I would have to agree. I may even go as far as say 2001 and up. I know my wifes late model year 99 has a distributer.
 
ehall said:
Okay good. Any differences between the '99 XJ and TJ in terms of tranny mating, exhaust, accessories, etc that I should be worried about? Thanks guys

Use the accessory brackets from the XJ. I want to say the PS pump mounts different on a TJ. And possibly the factory exhaust manifold, where it mounts to the downpipe.

Other than that, you should be good to go.
 
CanMan said:
Use the accessory brackets from the XJ. I want to say the PS pump mounts different on a TJ. And possibly the factory exhaust manifold, where it mounts to the downpipe.

Other than that, you should be good to go.


Don't the 99 or newer pumps considered an upgrade to the pre pumps? Thus being an desireable upgrade?
 
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