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Unread 07-24-2010, 06:03 PM   #1
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2000 TJ Wrangler 
Join Date: Jul 2010
Location: NCSU, NC
Posts: 199
2.5L to 4.0L

Im thinking about buying a 1998 se. the body has 170k but the engine has 106k so the owner claims. I know the se only came with a 2.5L but it now has a 4.0L.

Also do se models have ac because this one does.

Anything I should specifically look for to make sure the swap was done right in regards to engine, tranny, axles?

Also if you know the compression in psi of the cylinders that be great for a standard 1998 4.0L

How do i tell which transmission it has? it could be ax5 or 15 any code on tranny that would tell me?

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Unread 07-24-2010, 06:47 PM   #2
Wheelin98TJ's Avatar
1998 TJ Wrangler 
Join Date: Apr 2004
Location: , Southeast MI
Posts: 24,399
Check the motor mounts and how well they were installed. Look at the placement and make sure nothing looks strange. Check the welds.

The tranny can not be an AX-5 because that tranny does not bolt up to the 4.0.

I would check the wiring harness really well. Make sure it is not hacked together.

Compression should be 120-150 PSI.
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Unread 07-24-2010, 06:51 PM   #3
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2000 TJ Wrangler 
Join Date: Jan 2007
Location: Texas
Posts: 8,138
130-150 on the compression. Look at this place for picts on the trannys The AX15 Transmission - Novak Conversions

Is the exhaust manifold a two piece or one piece, two piece is 2000 and up.
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