Replace 3.3 with a 3.8?

[kentreg]

Greetings,

I have a 96 GC with 130K which we bought new and love it. I recently started towing a 2500 pound boat and so far, so good. The temp gauge never seems to budge higher than half way up and the tranny cooler seems to be doing it's job. We're thinking of keeping this van for several more years and my question is if the motor tires out would it be possible to install a remanufactured 3.8 liter in place of my current 3.3? A little more horsepower would be nice when towing. I assume it uses the same tranny?
Thanks in advance, Ken.

[conncarl]

Kent, this is an excellent question. Unfortunately, it seems like the Caravan won the "least likely to be modified" prize somewhere along the line.

It's tough to get an answer for where to find a higher capacity oil filter for the 3.3 (you can use a Motorcraft FL1A or equivalent, you'll get about ½ quart extra oil capacity and extended filter life), never mind engine swap info.

Still, the 3.8 is essentially a bored-out 3.3. Externally they are pretty much identical.

If you're serious about this swap, I would recommend stopping by an auto parts store when they are slow, and asking them to check a list of parts and see if the part number is the same for both applications (3.3 and 3.8). If the exhaust Y-pipe, the motor mounts, and a handful of other key parts are the same, then you can go a-hunting for a 3.8 donor van. It will have to be a 96 or 97 for maximum compatibility, there were changes to the 3.8 for the 98 MY and I don't know exactly what they were. If you find a 98 - 00 donor van you will have to do some more research.

Otherwise, make sure you get the ECU from the donor van and you should be good to go.

Carl

[Alphabravo]

I just put a 92 dodge caravan 3.3 motor into a 94 Chrysler T&C with a 3.8! And it wasn't difficult at all!! Here's what I found: You must swap the rear exhaust manifold, (The 3.8 had an EGR and the 3.3 didn't, maybe just a year/model thing?) Swap the upper AND lower intake plenum (The upper for the EGR thing again and the lower because the thermostat housing is slightly larger on the 3.3 which makes for problems connecting the rad hose. While you're swapping the intake, swap the fuel rail and injectors, along with the whole wiring harness (the connectors were slightly diffrenent). Also, the Cam Sensor and the Crank Sensor needed to be replaced to match the connectors. I swapped the tranny wiring harness too because it got damaged pulling out of the donor vehicle, but the connectors seems the same so you may not need to swap them. Surprisingly I didn't need to change the ECM or TCMs, although it shifted a little rough for a day until the TCM re-learned, I guess. Another thing, there wasn't much difference in power that I noticed even though I "downgraded". If you want to upgrade, maybe pulling a boat every little bit helps?

Good luck.

[Alphabravo]

Originally Posted by Alphabravo

I just put a 92 dodge caravan 3.3 motor into a 94 Chrysler T&C with a 3.8! And it wasn't difficult at all!! Here's what I found: You must swap the rear exhaust manifold, (The 3.8 had an EGR and the 3.3 didn't, maybe just a year/model thing?) Swap the upper AND lower intake plenum (The upper for the EGR thing again and the lower because the thermostat housing is slightly larger on the 3.3 which makes for problems connecting the rad hose. While you're swapping the intake, swap the fuel rail and injectors, along with the whole wiring harness (the connectors were slightly diffrenent). Also, the Cam Sensor and the Crank Sensor needed to be replaced to match the connectors. I swapped the tranny wiring harness too because it got damaged pulling out of the donor vehicle, but the connectors seems the same so you may not need to swap them. Surprisingly I didn't need to change the ECM or TCMs, although it shifted a little rough for a day until the TCM re-learned, I guess. Another thing, there wasn't much difference in power that I noticed even though I "downgraded". If you want to upgrade, maybe pulling a boat every little bit helps?

Good luck.

An additionnal note, I swapped the motor AND tranny, so if you plan on replacing just the motor, I'd check to make sure the tranny will mate up.

Good luck!

[HeadlessHorseman]

My '96 GC LE has the 3.8L motor and "Towing Package" (heavy suspension components, extra coolers for oil and tranyy, etc.). We tow a Coleman Popup (2700lbs) six to eight times each year for a total of, maybe, 2000 miles. We're also on our third transmission. You can change out your tranny fluid, filter and gasket every 15,000 miles and these transmissions still blow up every 79,000 miles or 3.5 years, whichever comes first.

Trust me... get a Ford pickup to tow your boat and leave the Caravan to hauling people. Been there, done that.