I have a 1998 Grand Cherokee Laredo with defunct 4.7L engine. A remanufactured engine is rather expensive. Two local mechanics with experience with Jeeps say that a Mopar 5.2L Magnum engine should swap easily. It's easier to get, less expensive and a better engine. I'm not totally convinced, however. Biggest issues I can think of are motor mounts, bell housing and crankshaft to torque converter/transmission mating. We would probably need the mopar computer as well. These guys have said that the computer plugs should be identical. Anyone have any experience with this particular swap?

 

The 4.7L V8 wasn't offered in the '98 Grand Cherokee. It wasn't available until the '99 Grand Cherokee.
If you have a V8 in your '98 Grand (ZJ) it is either the 5.2L (318), or the 5.9L (360) which came in the 5.9 Limited. Check your VIN # to see which engine you have.
And Welcome to CF!
Dan

 

I am very interested in the answer. We are facing the same situation. We have a 99 Jeep Grand Cherokee Limited with the 4.7 in need of an engine replacement. We have had a local mechanic tell us that replacing the 4.7 with the 5.2 is the better option than getting a used or rebuilt 4.7.

Is this right? What else will be needed?

Thanks for the help.

 

Welcome to CF.
You'd also have to replace the trans (or find an adapter)& the TCM, the PCM, and the wiring.
I'd much rather find a good 4.7L V8 than spend all that money for something that would be going backwards in technology. I'd find another mechanic too. What was he thinking?

 

X2! Does this mechanic have an engine swinging from a tree? The days of a simple engine swap have been over for two decades now.

 

Well said.

 

Old Hot Rod adage:
How fast can you afford to go?

You could put a Viper engine in your Jeep, it is possible.
Question: What makes you think it would be easier to a 318/360 than it would be the Viper engine? If my question sounds ridiculous, think twice. Its just a simple swap.

Ron

 

The saying was, "How fast can I go? How much money have you got?"

It's true any swap is possible, but that's not the issue here. Practicality is.
I have an '04 4.7L V8 WJ w/the 5-spd auto, and had a '97 5.2L V8 ZJ w/the 4-spd auto. While the ZJ might be better at towing, the WJ was better on gas and an all around better performing vehicle.

I'd put in another 4.7L V8, for more fun, less trouble, and a whole lot less expense.

 

No, you should find a new mechanic. Welcome to CF!

 

I would like to resurect this thread and I hope you folks can understand why. I live on the big Island of Hawaii. There are lots and lots of cheap 4.7 power mopars here with blown motors. Can't find the 4.7 on the island nearly as cheap, easy or plentiful as the 5.2. Shipping in is not an option that is economically reasonable.

Does anyone know of anyone making these swaps easier? Or has done it so I can capitalize on the fact that I would be the only one able to do it here?

 

Okay, here it is in a nutshell. The 4.0, 5.2 and 5.9 all use the same motor mounting locations. In '99, in order to mount the 4.7, they had to move the motor mounts farther rearward because of the 4.7s different CG. They also had to redesign the 4.0 block because of this. When doing that, the 4.0s oil filter was in the way, so they had to relocate that as well.

Moving the engine back make it necessary to move the trans and t/case as well making it necessary to go to cable shifting for both.

That's the way I see it. Correct me if I'm wrong, please.

The electronics are a separate topic.