2.5 to 4.0 swap

[Preston kott]

I have a 97 tj with the 2.5 automatic. I recently changed the gears to 4.56 so it would run better with 33’s. I’m only getting 65 mph on the interstate and would like more. I have access to a 2000 or 2001 grand Cherokee with the 4.0.The grand Cherokee is a 2wd. How hard would it be to swap out?
Will my transmission work? I know it would be easier to sell this one and buy one with a 4.0 but that’s not an option at this point because I won’t get the money I just put in it out.

 

[Chris]

Bad idea.

Your transmission will not work.

In addition, a 4.0 from a Grand Cherokee is going to bring on a whole set of complications, as there are many differences.

The smart thing to do is to sell your TJ and get one with a 4.0. If you’re not going to do that, look for a 4.0 out of a 97-99 TJ, including the transmission, wiring harness, etc.

If you’re a glutton for punishment, proceed with the Grand Cherokee 4.0 swap, knowing you’re in for a lot of surprises along the way.

 

[Preston kott]

Bad idea.

Your transmission will not work.

In addition, a 4.0 from a Grand Cherokee is going to bring on a whole set of complications, as there are many differences.

The smart thing to do is to sell your TJ and get one with a 4.0. If you’re not going to do that, look for a 4.0 out of a 97-99 TJ, including the transmission, wiring harness, etc.

If you’re a glutton for punishment, proceed with the Grand Cherokee 4.0 swap, knowing you’re in for a lot of surprises along the way.

Even with the complete vehicle ?

 

[Wildman]

I have a 1997 SE TJ but mine was a 5 speed and I looked into doing this swap also. Once I researched it I decided that if I was going to do the swap it made more sense to do a V-8 swap. For the amount of work that it takes to put a 4.0 into your rig it is almost the same amount of work to do the V-8 swap.

I'm not a expert on this and like Chris stated it would be a lot more work than it would be worth. Even if you have the complete vehicle there are still differences between a GC and TJ.

Look on your drive side door pillar and see what the build date on your TJ is. This matters since the early built TJ's have different wiring than later built TJ's.

 

[Preston kott]

Bad idea.

Your transmission will not work.

In addition, a 4.0 from a Grand Cherokee is going to bring on a whole set of complications, as there are many differences.

The smart thing to do is to sell your TJ and get one with a 4.0. If you’re not going to do that, look for a 4.0 out of a 97-99 TJ, including the transmission, wiring harness, etc.

If you’re a glutton for punishment, proceed with the Grand Cherokee 4.0 swap, knowing you’re in for a lot of surprises along the way.

would you have any recommendations on getting some of the speed back? Would a transmission swap be an option ?