Jeep Commander Forum banner

1 - 5 of 5 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
Avid reader of the forum, but new member. Figured no better day to finally join than today, because today was a really bad day! The Jeep gods have frowned upon me, my Commander overheated, for reasons we cant quite explain. Within a minute of overheating i managed to warp one of the heads, and most likely damage the block. Since i already have so much invested in this vehicle (and love it so) ive decided to replace the motor. Ill be doing the work myself and dont really mind it, or the additional work that comes with a larger motor. Currently im running the 3.7, but interested in other options (4.7 or 5.7). Curious to how people feel about thier particular motor, pros, cons, real mpg, towing capabillities, realiabillity, etc.... Or some input from others who have also upgraded thier motor.
 

Attachments

·
Banned
Joined
·
105 Posts
I'm not sure how much is possible. I think you have to swap everything from one vehicle to another, engine, wiring, ecu and so on.

The easiest is a direct swap but I may be uneducated on the other swap options.


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
3,037 Posts
Water pumps, as the bearing fail can blow out the seals and completely dump the coolant leading to a very quick overheat. If you continue to drive and put load on the engine you can damage the aluminum heads. Just a possibility, but you need to figure out what went wrong in the cooling system, else you'll just repeat it with the repaired engine.


With the electronic controls, and digital communications between all the modules, doing an engine swap to a different configuration can be very daunting.


It would require swapping over everything, wiring, electronics and then reconfiguring the body electronics. A lot of that can only be done with the dealer electronic tools, meaning towing it to the dealer and paying out the nose for them to reconfigure it, and hope they don't screw it up.


Not to mention, the 3.7L comes with a different transmission than the V8's. So you would have to swap in a new transmission as well.


So, your choice is, just do a direct replacement of the mechanical 3.7L engine and have the vehicle up and running. Or do an engine swap to one of the V8's and it will easily cost more than twice as much, swapping over electronics and different accessories, transmissions, figuring out dozens of problems that crop up from the misconfiguration, that you'll have to run to the dealer and pay through the nose to analyze and correct with their electronic tools, that will take you 3 times longer than a direct replacement.


Engine swaps today are nothing like what they used to be when cars were much simpler. Just like the, "Can I convert my 2WD version pick-up/Jeep to 4WD" question, after you look at everything involved, you learn it would be easier to just sell your vehicle and buy one that was already equipped with the stuff you want.


BTW, what evidence do you have the engine block is damaged? Aluminum heads warp all the time without damaging the block. Your solution to getting your Jeep back up and running may be even cheaper and easier with just buying a new or rebuilt cylinder head and swapping it in.


Although the timing chain install does NOT look fun or easy on these motors. And btw, I've seen someone that bought a cheap no-name timing chain kit off ebay for the 3.7L/4.7L motors, likely made in china, the chain ending up snapping in less than 100k miles and taking out the motor. Get a quality timing chain.
 

·
Registered
Joined
·
176 Posts
Agree with what's already been stated and I'll add my 2 cents...

The 3.7 is notorious for the valve seats on the #2 cylinder (passenger/right side closest to the front) dropping when it overheats and doing damage to the cylinder and piston top. The heads will warp since they're aluminum and need machined but if the valve seat did NOT drop into the cylinder the repair is actually pretty straightforward. I swapped an '07 3.7 into my '03 KJ and had to put in a new cam sprocket and crankshaft reluctor (timing) ring to match the computer on my '03 so I had to tear the new engine down to the long block. The timing chain procedure is tedious but not difficult - and if you only have to pull the head for repair then the process is much easier.

If you do the work yourself the project should be less than $500 even if both heads need work. Just have a good torque wrench and broad assortment of tools, NEW head bolts (DON'T reuse the old ones - they are Torque To Yield [TTY] bolts and will stretch/break if reused) and you'll be back up and running in a weekend after getting the head(s) back from the shop.

Keep us posted.

Bob
 

·
Registered
Joined
·
9 Posts
Once you understand the CANbus communication, swaping in a new drivetrain is not that bad. The key here is to get the engine and trans, plus wiring harnesses and PCM (ECM/TCM) from the same year the vehicle is going in to. Even easier if you get it out of the same make and model. The ABSM, PCM (some vehicles have a separate TCM and ECM) communicate on a priority 1 network. The BCM has some functionality that communicates on a priority 2 network with the other modules. As long as the engine sensors are sending information to the Module and the module know what engine it's trying to run, it's going to be happy. Same with the transmission. And as long as those 2 can talk to each other they are happy. That's why you get them out of the same vehicle along with the harness and modules. Because the BCM is of a lower priority, it's not so specific. But to make the communication aspect of it easy on the end user, make, model, and year all being the same for the vehicle receiving the swap and the vehicle donating to the swap, there is minimal relearn processes.

I would swap in the 3.0 turbo diesel out of the eco diesel ram and the 8 speed transmission personally.
 
1 - 5 of 5 Posts
Top