After a few dozen searches and sifting through 20+ pages of threads, I have not found an answer. Apologies if this has been covered but I am wondering if anyone has done a LS3 swap on a 2004 Montero Sport?

I've seen LS1s maneuvered into earlier generation Monteros. The LS1 5.7L V8 fits snuggly in the older, smaller engine bays. Since the 2004 Montero Sport has a larger bay, was wondering if a LS3 (6.2L V8) could fit under the hood?

Any info or redirection to other threads/forums would be greatly appreciated.


Cheers.

 

obviously I’m replying four years after the original poster - OP. So, I want to bump this thread and see if anyone wants to answer it, but also, I’m going to briefly comment with my own thoughts. For me, any swap that that doesn’t involve keeping the original engine or original transmission has proved really problematic. Specifically, I think there’s some ways to adapt the 6G72 to a GM automatic like the TH400 or to adapt it to the Ford modular bell pattern. Likewise, I once saw an adapter plate to put the Volkswagen 1.9 TDI onto the Mitsubishi gearbox. Of course, neither of those are very good options. Therefore, if anything ever happens to my engine and transmission my direct course of action is to try and complete a full swap with a high degree of difficulty because there’s no kit I’ve ever heard of. There might be kits for the Montero, but not for the Montero Sport because the Montero Sport is literally a different vehicle entirely - for whatever reason. I spent a lot of time thinking and for me the main considerations that prove problematic are these:

(1), the vehicle weighs more than 4000 pounds -therefore, a transmission that proves reliable in most scenarios when used in a typical 3000 pound car are not guaranteed to be equally as reliable in a vehicle that heavy. (2), most manual transmissions made for trucks and jeeps that have a proven track record of moving a 4000 pound vehicle are very short in length from the bell-housing face to the shifter location - therefore, the problem experienced is that the shifter location (when installed) would literally be somewhere under the dashboard because there’s approximately 24 inches from the firewall to the original shifter location of the automatic transmission. unfortunately, I’m assuming there was never a manual transmission offered for the Montero Sport in America - therefore, it would have to be shipped from overseas like Japan or the Philippines and there’s no guarantee that it would just bolt onto the 6G72. (3), the transmission tunnel is probably very small - therefore, trying to get one of the GM automatic transmissions in there is probably a problem however with the transmission being too big and the tunnel being too small. NOTE: I haven’t measured anything under there. (4), another problem that puts most of the typical viable manual transmissions like the NV4500, NV3550, M5R2, T18, etcetera etcetera, is that there’s no guarantee that the transfer case would be in the right place because the front differential (and all of its’ parts) are very far back and close to the driver meaning a transfer case shoved up far probably wouldn’t work because the driveshaft might be too short OR because the transfer case might not fit in a non-original location. Sorry this is a lot of writing, but these are all the things I’ve had problems with when thinking about how to do this; and also, please know that I haven’t actually done any measuring underneath the vehicle. The last thing is simply the engine problem - regardless of what type of engine you want. I doubt there is ever going to be more than 28 inches of room from the firewall to the radiator. I’ve measured that many times and it literally looks like the bell-housing face to the radiator is closer to 22 inches. That basically removes any possibility of any engine other than a V6 or an I4 - unless you’re going to do some serious modification. But again, please know, I haven’t measured a ton and these are all kind of just preliminary things where I’ve been trying to find the perfect option in case anything ever happens and I get the opportunity too spend money fixing it instead of throwing it away.

 

This is an excellent question/concern. What engines are adaptable as replacements in the future? Do we just accept the death of the Montero?

 

With enough money and cutting+welding tools any engine/transmission can be swapped/adapted. Unfortunately not many of us find ourselves in this position 🫤

 

Exactly. Sure, a solid axle conversion with lift and whatever engine after doing serious cuts and welds is best, however, it’s just too expensive. So, the Montero and Sport in the late 90s and early 2000s, are basically only using three different engines from the factory and two different transmissions:

4D46 diesel I4. 4M41 diesel I4. And6G7x like 6G72, 6G74, and 6G75 which probably are 3.0L, 3.4L, 3.5L probably. The transmissions are V4A51 automatic 4WD or R4A51 automatic RWD, then V5MT1 and V5M31 manual transmissions… HOWEVER, there are three DIFFERENT bellhousings.

here in America, I think they only sold the four-door version. So when the four-cylinder diesels are used in short wheelbase, two door, canvas top ones, they might easily be 500 pounds lighter weight, therefore, the risk of trying to use a rare engine from overseas combined with maybe the vehicles we have here being heavier on average, seems like too much for risk. However, those engines are probably guaranteed to fit because they’re the original equipment. So, again, the ideal scenario is to find a transmission with a small enough shape to fit in the tunnel while also being long enough to have the shifter in the correct location and the transfer case in the correct location without having to modify any of the tunneling for the transfer case or transmission whatsoever. If that is solved, then it’s also a question of what engine is gonna fit in 22 inches of engine bay length because that is very short.