Whew, that was a lot to read! I've been reading this entire thread and taking detailed notes over the course of the past week.
Some of you may be following my completely ignorant deep dive into rebuilding nearly every mechanical system of my FZJ80 here. A couple years back I bought a 5.3 LM7 (Gen 3), intending to swap it into either my dad's CJ-7 or my 1965 Impala. I wanted to get some 'simple' swap experience before attempting an FJ80 swap due to the more advanced wiring/integration. I pulled the 1FZ for a refresh and, now that it's out, I've decided that if I'm going to LS swap the 80 there's no better time than now. I've read a ton of build threads in addition to this thread, but I'm still trying to come up with a solid game plan. Budget is a fairly large factor, but I'd rather spend the money and do it right rather than have to re-do it in the future, so I'm considering all my options. Since this swap involves extensive modification to both the vehicle and engine harness, I think my best option is to learn how to do the wiring and modifications myself.
I think the transmission choice is my most difficult decision. Due to the cost of the Mark's adapter and the fact that they aren't interchangeable (right?), once I pick a transmission I'm going to have to stick with it. Unless someone here says something to change my mind, I've ruled out the 4L60e family. Though they have better gearing than the 4L80e and weigh considerably less, I'm worried about reliability (see goals), and around here they're around $1500 to rebuild. I think I'd feel comfortable buying and running a used 4L80e. I'd really like a 6L80e, as it seems to be the best in terms of reliability, driveability, and gearing, but it would require the purchase of a Gen IV engine (which I'm not opposed to) and I'm concerned about increasing the difficulty of the swap (asked about below).
Options
Goals
Thanks for letting me get my thoughts on paper. Hoping some of you might have some opinions or advice
Some of you may be following my completely ignorant deep dive into rebuilding nearly every mechanical system of my FZJ80 here. A couple years back I bought a 5.3 LM7 (Gen 3), intending to swap it into either my dad's CJ-7 or my 1965 Impala. I wanted to get some 'simple' swap experience before attempting an FJ80 swap due to the more advanced wiring/integration. I pulled the 1FZ for a refresh and, now that it's out, I've decided that if I'm going to LS swap the 80 there's no better time than now. I've read a ton of build threads in addition to this thread, but I'm still trying to come up with a solid game plan. Budget is a fairly large factor, but I'd rather spend the money and do it right rather than have to re-do it in the future, so I'm considering all my options. Since this swap involves extensive modification to both the vehicle and engine harness, I think my best option is to learn how to do the wiring and modifications myself.
I think the transmission choice is my most difficult decision. Due to the cost of the Mark's adapter and the fact that they aren't interchangeable (right?), once I pick a transmission I'm going to have to stick with it. Unless someone here says something to change my mind, I've ruled out the 4L60e family. Though they have better gearing than the 4L80e and weigh considerably less, I'm worried about reliability (see goals), and around here they're around $1500 to rebuild. I think I'd feel comfortable buying and running a used 4L80e. I'd really like a 6L80e, as it seems to be the best in terms of reliability, driveability, and gearing, but it would require the purchase of a Gen IV engine (which I'm not opposed to) and I'm concerned about increasing the difficulty of the swap (asked about below).
Options
- 5.3L LM7 'As-Is' / 4L80e - It has 165k on it and I heard it run/checked it over before the guy pulled it. I'll admit it's a little hard for me to think of installing it as-is while it's out of the vehicle with everything accessible, but this is the most budget-friendly option. I could sell this engine as it sits for ~$800 (so for comparison purposes that's what I'm putting here) and I could get a used 4L80e for ~$800, total cost $1600.
- 5.3L LM7 Refresh / 4L80e - I figure it'll be around $1200 to 'refresh' the LM7, replacing all seals, bearings, rings (reusing pistons), and having the heads gone through. That'd bring the total cost to $2800 (approaching Gen IV/6L80 territory).
- Gen IV LY5 5.3L or LY6 6.0L / 6L80e - I've seen low-ish mileage (~130k-150k) combo's on eBay for around $3500, a bit more for the 6.0L. It seems I could save a at least a few hundred if I bought the engine and transmission separately, but I've heard horror stories of these engines and transmissions from different vehicles (asked about below).
Goals
- Reliability - If I can't rely on this thing to get me to remote areas and home there's no point in owning an 80.
- Ability to use 87 octane and get decent fuel mileage.
- Power - I'm not sure if the increased fuel consumption and reduced range of a 6.0L would make up for the increase in power. I honestly didn't think the 1FZ was too bad.
- I've seen a lot of different motor mounts used over the years, which ones do you recommend now?
- It's been mentioned repeatedly that sticking with the GM mounts is recommended due to the way they isolate the vibrations of these engines, but I haven't seen anyone who has done this.
- These from The Land Cruiser Shop are tempting, as they're made for our application and they're finished nicely. As others have said though, I'd be stuck with the position they chose. I emailed them about availability on 11/16 and still haven't heard back.
- Mark's have difficulty with LHD vehicles, but I could modify them and it appears they may be included with the 6L80e kit, saving me money.
- Dirty Dingo kits seem to be a popular option, I think most go with the hot rod kit?
- How much more difficult is it to swap a 6L80e over a 4L80e, both in terms of fitment and wiring? Hoping @bloc, @Lionsgarage, @MAG58, @Squad1, @TonyP can shed some light.
- Do any of you wish you'd gone with a 5.3L or 6.0L rather than what you went with?
Thanks for letting me get my thoughts on paper. Hoping some of you might have some opinions or advice