Series 80 engine rebuild or swap options? (1 Viewer)

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How many guys do you know with 4l75e transmissions that have failed?
I don't know anyone with enough miles on one to say seeing as they are so new.

I'm guilty of grouping them in with the 4l60e/65e/70e as I see them as the factory offering all the same upgrades done when rebuilding an earlier transmission.
 
I chose to rebuild my engine 100%.
Bottom end/top end.
Everything is brand new.
Almost everything under the hood now is replaced and brand new. I have now roughly 4k miles on everything under the hood.
It was not low cost and sure I may have been able to do an LS swap or something for less.
But now I have the Toyota reliability and it’s all stock.
 
I believe a 4l75e is basically all the higher end stuff from sonnax put together. As far as a 4l60e, four things especially I think are important: firm shifts to help the clutches, not letting it get too hot, not fully programming out torque management, and you want to keep the fluid clean. My basic 4l60e rebuild is doing pretty well so far with 450ish torque in front of it. I'm not really worried about the 4l60e blowing up. If it does I'll just toss another one in. It cost about 700 bucks for a 4l60e basic rebuild parts and labor not including the converter with me doing the removal and install. It's pretty easy to pull out. The joy I get from driving it in the interim is worth it to me.
 
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Great thread

As someone with both a LT1 swapped (gen V) 80 with an 8l90e trans and a 1FZ truck with a NFW black box I can maybe clear up some of the inaccurate assumptions.

LT1 conversion (Or LS3, for that matter):
  • Chicks dig 465HP
  • Truck will spin all 4 tires on dry pavement and has zero trouble doing 100MPH.
  • Get your suspension and steering right. You'll really notice the difference. I have @Delta VS arms on the
    front and panhard correction on the back and they make a night-and-day difference at speed.
  • No one in a small town is going to be able to fix it. Yeah, I'm sure someone could replace a head gasket, but your problem will more likely be electrical and related to how the GM install interfaces with the Toyota body wiring and that's going to be a head scratcher for most.
  • If you read the V8 conversion thread you'll see a lot of people struggling with interfacing the GM install with the Toyota body. Don't assume that will go smoothly.
  • You'll have weird problems and be less reliable on the trail. I still throw a random "accelerator pedal desync" code which effectively turns the input off from my gas pedal. I also boiled fuel in my gas tank. Always fun.
  • As many have said, probably won't last as long as a 1FZ, but can also be rebuilt more readily and by more places.
  • Going to an aluminum block and dropping 200lb off the front axle is nice.
  • Gen 5s run hot. Be prepared for some heat mitigation (Gen 4, not so much)
  • Lots of other options for driveline mods (If you want to run an Atlas, etc.)
1FZ:
  • Makes an anemic amount of power by modern standards. In 4WD you'd be lucky to have 140HP at the wheels.
  • Superchargers are hard to find, expensive and old. Turbo kits are also expensive and have spotty support.
  • They basically last forever no matter how much you abuse them. Sure, I can't get parts readily in a small town, but I also likely don't need them and the truck can probably limp home.
  • More and more parts will continue to become NLA. At some point (who knows how long from now) keeping them running will be a real challenge.
  • The transmission really doesn't like being at absurd angles. Probably not an issue for most people.
  • Holy crap they're heavy
  • Probably better for resale if you're looking to sell to purists on BaT
To be honest, I like both. If I could get another 100HP without having to sell my left kidney I'd be a lot happier with the 1FZ. The weight is a killer while wheeling; our trucks are already pretty heavy. That forklift engine up front isn't helping.
 
I find the logic of not building sn 1fzfe now "because parts are gonna be NLA in the future" weird.
All the parts are available now. Parts availability isn't really a roadblock to building one now.
It's like saying "i wouldn't install an LS engine, coz they'll do making them in the future".

There may be a load of other reasons not to go 1fz-fe, such as price of parts.

If you rebuild an 1fz-fe now worry about parts being NLA in another 300k miles
 
I find the logic of not building sn 1fzfe now "because parts are gonna be NLA in the future" weird.
All the parts are available now. Parts availability isn't really a roadblock to building one now.
It's like saying "i wouldn't install an LS engine, coz they'll do making them in the future".

There may be a load of other reasons not to go 1fz-fe, such as price of parts.

If you rebuild an 1fz-fe now worry about parts being NLA in another 300k miles
My point is longevity of investment. To your point, if you perform a complete rebuild now ... sure, you're probably fine for 300k miles. However we rarely rebuild everything and peripherals like the MAF, distributor, wiring harnesses, injectors, etc will all start to (or have) become NLA so the investment could easily be hobbled by needing to find used parts in the not-too-distant future. In contrast, I doubt I'll have any trouble driving to the local parts store and finding parts for my domestic V8 at any point in my lifetime.

It's not a reason to not rebuilt a 1FZ, just another consideration.
 
My point is longevity of investment. To your point, if you perform a complete rebuild now ... sure, you're probably fine for 300k miles. However we rarely rebuild everything and peripherals like the MAF, distributor, wiring harnesses, injectors, etc will all start to (or have) become NLA so the investment could easily be hobbled by needing to find used parts in the not-too-distant future. In contrast, I doubt I'll have any trouble driving to the local parts store and finding parts for my domestic V8 at any point in my lifetime.

It's not a reason to not rebuilt a 1FZ, just another consideration.

Consider that it took 25 years for my 80 to reach 300k and maf, injectors, engine wiring harness are all still readily available from Toyota. I’d be more concerned about governance and our ability to legally drive or afford to run gas powered cars even within the next decade.
 
Consider that it took 25 years for my 80 to reach 300k and maf, injectors, engine wiring harness are all still readily available from Toyota. I’d be more concerned about governance and our ability to legally drive gas powered cars even within the next decade.
That's very true, too.
 
I chose an alternative lifestyle. :flush:




1HDFTE.jpeg
 
My point is longevity of investment. To your point, if you perform a complete rebuild now ... sure, you're probably fine for 300k miles. However we rarely rebuild everything and peripherals like the MAF, distributor, wiring harnesses, injectors, etc will all start to (or have) become NLA so the investment could easily be hobbled by needing to find used parts in the not-too-distant future. In contrast, I doubt I'll have any trouble driving to the local parts store and finding parts for my domestic V8 at any point in my lifetime.

It's not a reason to not rebuilt a 1FZ, just another consideration.

I think there's enough aftermarket support for these to keep them viable.
When things that are NLA become critical failure item in big enough numbers, aftermarket suppliers will step in with replacements or upgrade/ adaptations in some form.



Hopefully. . .
 
Great thread

As someone with both a LT1 swapped (gen V) 80 with an 8l90e trans and a 1FZ truck with a NFW black box I can maybe clear up some of the inaccurate assumptions.

LT1 conversion (Or LS3, for that matter):
  • Chicks dig 465HP
  • Truck will spin all 4 tires on dry pavement and has zero trouble doing 100MPH.
  • Get your suspension and steering right. You'll really notice the difference. I have @Delta VS arms on the
    front and panhard correction on the back and they make a night-and-day difference at speed.
  • No one in a small town is going to be able to fix it. Yeah, I'm sure someone could replace a head gasket, but your problem will more likely be electrical and related to how the GM install interfaces with the Toyota body wiring and that's going to be a head scratcher for most.
  • If you read the V8 conversion thread you'll see a lot of people struggling with interfacing the GM install with the Toyota body. Don't assume that will go smoothly.
  • You'll have weird problems and be less reliable on the trail. I still throw a random "accelerator pedal desync" code which effectively turns the input off from my gas pedal. I also boiled fuel in my gas tank. Always fun.
  • As many have said, probably won't last as long as a 1FZ, but can also be rebuilt more readily and by more places.
  • Going to an aluminum block and dropping 200lb off the front axle is nice.
  • Gen 5s run hot. Be prepared for some heat mitigation (Gen 4, not so much)
  • Lots of other options for driveline mods (If you want to run an Atlas, etc.)
1FZ:
  • Makes an anemic amount of power by modern standards. In 4WD you'd be lucky to have 140HP at the wheels.
  • Superchargers are hard to find, expensive and old. Turbo kits are also expensive and have spotty support.
  • They basically last forever no matter how much you abuse them. Sure, I can't get parts readily in a small town, but I also likely don't need them and the truck can probably limp home.
  • More and more parts will continue to become NLA. At some point (who knows how long from now) keeping them running will be a real challenge.
  • The transmission really doesn't like being at absurd angles. Probably not an issue for most people.
  • Holy crap they're heavy
  • Probably better for resale if you're looking to sell to purists on BaT
To be honest, I like both. If I could get another 100HP without having to sell my left kidney I'd be a lot happier with the 1FZ. The weight is a killer while wheeling; our trucks are already pretty heavy. That forklift engine up front isn't helping.
"Cogito Ergo Absurdum"
 
Recently overheated my FJ80 returning from a hunting trip. 250k on it. Drove it less than five minutes before I could get it cooled down. Engine began what I would describe as a "sticking lifter" sound. Drove on home about 60 miles. Parked it and later returned to drain the oil. All looked good as it drained but when I turned the oil filter over there was the dreaded engine glitter.

So, I am planning to pull the engine and have the long block rebuilt. I live in the Houston area, and I don't think I'll have any trouble with getting the machine work done on it.

Not too sure if I'm mine gave up early at approximately 250k, but I'm not all that disappointed. I've done the transmission, birfields, suspension, brakes, exhaust, paint, interior, and everything else so pulling the engine and getting rid of oil leaks, rusty exhaust etc.. is about all that is left.

I'll be asking questions along the way, but after just replacing the transmission due to cracking the case of the old one I didn't have the heart to do the LS swap.
 

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