I just rolled 176000 miles on my truck and it is a work truck and i go traveling on the road a bit. I have been thinking about putting a new motor in, while my motor seems fine and only burns maybe half a quart every 3000 miles unless I am traveling doin 85 it burns a little more oil I dont want to be stranded on the road somewhere. Will a 4.2 out of a 2007 or 08 or 09 for that matter bolt up and will everything still be the same?

 

The 4.2 was discontinued in 2008, the 2009 line up has no v6 anymore, until the ecoboost comes to play.

Back on topic though, the engine is basically the same, besides the hydrolock issue the 98's had. You may or may not need a new computer, but I think that it will work.

Someone else will eventually chime in.

 

No a 2005-2008 4.2l v6 engine will NOT work correctly, unless you want to spend the money on doing a lot of swapping of simple stuff.

Changes that were made from the OBS to the NBS:

1. Electronic Throttle Body
2. Plastic Intake Manifold
3. Different connectors for the wiring harness.
4. No Idle Air Controller

And a few other things.

Pretty much anything from 97-03 will work fine.

 

well I am looking at getting a motor out of a wrecked truck so it will be a swap of everything minus accessories or will those issues matter aswell? As far as the harness, how much of a pain would it be to swap connectors?
Also, what was the issues with the 98 4.2? Like I said I have 176000 and the only things I have replaced are the alternator and clutch other then oil and brakes and some balljoints.

 

4.2's with a build date earlier than 1/15/98 had bad intake manifold gaskets. Avoid as a replacement.

 

What it sounds like with your old engine is the head gasket going.

These engines last a very long time if the head gasket it changed. They are very durable. 176k, the engine is just getting broken in, except for the gasket.

Another thing you might want to try before doing anything is try some Lucas fuel treatment, your piston rings might be hard from the ethanol in todays fuels and its allowing some oil to get past the rings.

I've been adding some to my truck's fuel because of the non-lubricating properties of ethanol, and I've noticed a dramatic improvement.

 

Why not buy a rebuilt long block and use your existing components? Manifolds, fuel injection, pulleys, etc. Anyone out there done this? MM.

 

just make sure you put the tailgate down before you do the swap