LM2 3.0 Duramax Swap into a 1997 80 Series
So here's how this one started. A customer brings in a '97 40th Anniversary Edition 80 Series, 280k on the clock, blown head gasket. Thing had been beaten on its whole life — you could tell just looking at it. I bought it off him, figured it deserved better than getting parted out. Wanted something I could actually take on trips, do some wheeling, camp out of. You know, use it like it was meant to be used.
Spent some time thinking about what engine made sense. Landed on the LM2 3.0 Duramax. Best decision I made.
The Donor
Found a Global A Silverado LM2 and 10-speed with only 10k miles on it. Basically a new engine. Pulled both and got to work.
The transmission is the GM 10L80 — and before anyone says anything, yeah I know it has a reputation. But honestly that reputation comes from the heavy half-ton trucks in the early days, and even then the hardware wasn't really the problem. It was the calibration. In a lighter application like this it's a totally different animal. And here's the thing nobody talks about — the Isuzu/Duramax TCM calibration is the best of any 10-speed variant I've driven. Shifts are crisp and confident, none of that lazy hunting around you get with some of the gas engine tunes. Night and day difference.
The Kit
I run Torfab — we do Land Cruiser work for a living and we make our own adapter housing, which is what turns this into a genuine bolt-in to the existing 80 Series frame mounts. Between those two pieces the foundation of the swap is pretty sorted before you even get into the fun stuff.
The Challenges (and a Few Surprises)
Intercooler — This was the head scratcher. The LM2 runs an air-to-water intercooler and finding somewhere to put it took a while. Eventually I flipped it and mounted it on the back of the engine. Hood clearance is... let's just say it fits. I've thought about going air-to-air but honestly the truck runs so well I'm not touching it.
Thermostat and power steering — The electronic thermostat had to go, that's just part of the deal with this swap. Drew the Car Guy has an adapter bracket for it that works perfectly. Grabbed his power steering pump bracket at the same time — both are well thought out, no complaints.
ECM/TCM — Both computers need to be unlocked with HP Tuners to work in a new vehicle. If you don't want to mess with that side of things, Mitch at Swaptime has a harness and computer combo that comes already sorted. That's probably the easier path for most people.
Exhaust — I'll be honest, I was dreading this part. Turns out the turbo exit faces forward so routing the exhaust was way easier than I expected. One of those happy surprises you don't take for granted.
Cooling — We run our own PWM fan kit with a Lingenfelter controller. Works great. Fan barely ever comes on. Make of that what you will.
Intercooler heat exchanger — Took some hunting to find the right one but once I had it the fitment was spot on.
The Shakedown
Here's where it gets a little unhinged. I finished this whole conversion outside under a canopy because the shop was packed and I wasn't waiting. Put about 50 miles on it, decided it felt good, and drove to Moab for Cruise Moab. By the time I got home I had 3,000 miles on a swap I'd finished the week before. Lot of that highway miles at 80-90 mph. The truck didn't care at all — just settled right in. Not exactly a textbook break-in but I'd say it passed.
How Does It Drive?
It's the best engine I've ever put in a Land Cruiser. I know that sounds like something you say, but I mean it. The torque is right there immediately, power delivery is smooth and linear, the whole truck just feels planted and confident in a way it never did with a gas engine. Hard to put into words — it just feels right.
Fuel economy on my last fill-up was 22.5 mpg. I should mention I have a pretty heavy foot, so take that for what it's worth. Someone with more self control would probably do better. I'm working on it, healing is a process
Bottom Line
If you've got a tired 80 and you're wondering if the LM2 is worth the effort — it is. It's not a simple swap but it's also not as scary as it might look on paper. The ecosystem around it is solid, the calibration side is manageable, and the end result is a truck that just makes sense.
So here's how this one started. A customer brings in a '97 40th Anniversary Edition 80 Series, 280k on the clock, blown head gasket. Thing had been beaten on its whole life — you could tell just looking at it. I bought it off him, figured it deserved better than getting parted out. Wanted something I could actually take on trips, do some wheeling, camp out of. You know, use it like it was meant to be used.
Spent some time thinking about what engine made sense. Landed on the LM2 3.0 Duramax. Best decision I made.
The Donor
Found a Global A Silverado LM2 and 10-speed with only 10k miles on it. Basically a new engine. Pulled both and got to work.
The transmission is the GM 10L80 — and before anyone says anything, yeah I know it has a reputation. But honestly that reputation comes from the heavy half-ton trucks in the early days, and even then the hardware wasn't really the problem. It was the calibration. In a lighter application like this it's a totally different animal. And here's the thing nobody talks about — the Isuzu/Duramax TCM calibration is the best of any 10-speed variant I've driven. Shifts are crisp and confident, none of that lazy hunting around you get with some of the gas engine tunes. Night and day difference.
The Kit
I run Torfab — we do Land Cruiser work for a living and we make our own adapter housing, which is what turns this into a genuine bolt-in to the existing 80 Series frame mounts. Between those two pieces the foundation of the swap is pretty sorted before you even get into the fun stuff.
The Challenges (and a Few Surprises)
Intercooler — This was the head scratcher. The LM2 runs an air-to-water intercooler and finding somewhere to put it took a while. Eventually I flipped it and mounted it on the back of the engine. Hood clearance is... let's just say it fits. I've thought about going air-to-air but honestly the truck runs so well I'm not touching it.
Thermostat and power steering — The electronic thermostat had to go, that's just part of the deal with this swap. Drew the Car Guy has an adapter bracket for it that works perfectly. Grabbed his power steering pump bracket at the same time — both are well thought out, no complaints.
ECM/TCM — Both computers need to be unlocked with HP Tuners to work in a new vehicle. If you don't want to mess with that side of things, Mitch at Swaptime has a harness and computer combo that comes already sorted. That's probably the easier path for most people.
Exhaust — I'll be honest, I was dreading this part. Turns out the turbo exit faces forward so routing the exhaust was way easier than I expected. One of those happy surprises you don't take for granted.
Cooling — We run our own PWM fan kit with a Lingenfelter controller. Works great. Fan barely ever comes on. Make of that what you will.
Intercooler heat exchanger — Took some hunting to find the right one but once I had it the fitment was spot on.
The Shakedown
Here's where it gets a little unhinged. I finished this whole conversion outside under a canopy because the shop was packed and I wasn't waiting. Put about 50 miles on it, decided it felt good, and drove to Moab for Cruise Moab. By the time I got home I had 3,000 miles on a swap I'd finished the week before. Lot of that highway miles at 80-90 mph. The truck didn't care at all — just settled right in. Not exactly a textbook break-in but I'd say it passed.
How Does It Drive?
It's the best engine I've ever put in a Land Cruiser. I know that sounds like something you say, but I mean it. The torque is right there immediately, power delivery is smooth and linear, the whole truck just feels planted and confident in a way it never did with a gas engine. Hard to put into words — it just feels right.
Fuel economy on my last fill-up was 22.5 mpg. I should mention I have a pretty heavy foot, so take that for what it's worth. Someone with more self control would probably do better. I'm working on it, healing is a process
Bottom Line
If you've got a tired 80 and you're wondering if the LM2 is worth the effort — it is. It's not a simple swap but it's also not as scary as it might look on paper. The ecosystem around it is solid, the calibration side is manageable, and the end result is a truck that just makes sense.
