I don't know how anyone can say that in good faith unless you're running stock tires and no armor. I've driven a 1FZ LC (35s and armored) at sea level and it still is an awful experience.
Series 80 engine rebuild or swap options? (2 Viewers)
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I don't know how anyone can say that in good faith unless you're running stock tires and no armor. I've driven a 1FZ LC (35s and armored) at sea level and it still is an awful experience.
CharlieS
GOLD Star
I run a stock '94 80 with steel front bumper (w/winch), rear bumper, sliders and skids with 35 MTs on steelies. And it is perfectly fine. I dont have second or third row seats though, so am offset a little there. I live in a rural area and rarely need to go interstate highway speeds though. This is my third 80 series (one that I eventually put a TRD supercharger on for towing a camper trailer), so I do have some seat time in 80s.
With over 300k miles on my 1FZ, I often contemplate the eventual need for a rebuild or perhaps considering a swap. I've been with my truck since it had 190k miles, and for the last 60k, I've enjoyed the added power of a supercharger. Living at 8,000 feet and regularly tackling the I70 from Denver to Glenwood Springs, I can confidently say that power has never been an issue.
Even with the challenges of high altitude, my truck, equipped with a supercharger, pretty easily maintains 75 mph up every grade on I70. I've attached a video of a moment topping out on Eisenhower Tunnel, cruising at 75. It's worth noting that during this recording, my truck was loaded with 37-inch mud terrains, a front bumper with a winch, a rear bumper with a full-size spare, sliders, a roof rack, and my mountain bike on the back.
The addition of the supercharger has been a game-changer for my 25+-year-old truck. It took just an afternoon to install, and since then, I've had no issues. The responsiveness to boost and the continued reliability of these trucks, despite their age, is truly impressive. I genuinely believe I wouldn't still own my 80 if it weren't for the supercharger. For that, I feel like I owe something to my truck to keep it 1FZ, it has been very good to me.
Looking ahead to the inevitable rebuild or swap, my primary desire is to have a manual transmission, driven purely by personal preference. Bummer there isn't a seemigly great solution for the 1FZ or LS swap. H151F someday maybe.
Even with the challenges of high altitude, my truck, equipped with a supercharger, pretty easily maintains 75 mph up every grade on I70. I've attached a video of a moment topping out on Eisenhower Tunnel, cruising at 75. It's worth noting that during this recording, my truck was loaded with 37-inch mud terrains, a front bumper with a winch, a rear bumper with a full-size spare, sliders, a roof rack, and my mountain bike on the back.
The addition of the supercharger has been a game-changer for my 25+-year-old truck. It took just an afternoon to install, and since then, I've had no issues. The responsiveness to boost and the continued reliability of these trucks, despite their age, is truly impressive. I genuinely believe I wouldn't still own my 80 if it weren't for the supercharger. For that, I feel like I owe something to my truck to keep it 1FZ, it has been very good to me.
Looking ahead to the inevitable rebuild or swap, my primary desire is to have a manual transmission, driven purely by personal preference. Bummer there isn't a seemigly great solution for the 1FZ or LS swap. H151F someday maybe.
I imagine if you could find a supercharger kit brand new at a much more reasonable price, you might see more people going that route over engine swapping.
$5k for a used unit is a tough pill to swallow. Nevermind the fact that don't come up for sale that often. The 1FZ does respond really well to boost and it's certainly going to help at elevation (where it's needed the most).
Definitely much easier to get your money back from a supercharger though and return the vehicle back to factory.
Very true. I was very lucky, finding another 80 with a SC and donating it to my truck. It will be fun to see when LandTank gets his supercharger kit to market with a modern blower design.
Then the problem is sorting out what's quality done vs someone's slop together swap. If it's OEM, at least you know it started out right...
Also to be considered is the crowd at BaT is likely to be more conducive to hot rods of any flavor than other sites. Cars and Bids tends to be more stockish, for instance. As for the lacking in power argument. other collectors more interested in originality would look for the TRD supercharger.
Merging issues?!?
That's why we install all that that body armor...
Has anyone installed, say, a Tremec 5-or-6-speed manual X-mission behind an LS?
Totally different market.
There is very few V8 for wheel drives in the Australian market.
A V8 conversion into something that never had a V8 is always gonna sell well here because, V8.
Wouldn't matter if the V8 in question was a toral piece of shìt, it's a V8. If it sounds like a V8, thats money in the bank!
You also see LS conversions where the owner has emptied the ARB accesories catalogue onto the truck as well, repainted, shiny wheels, big meats, and lift etc etc asking $100k. These sit for sale for a long time
I enjoy driving my fzj80. It's bone stock except for 33" tyres.
It is 5 speed manual though.
Irs fun to drive. I've owned far more powerfull cars in the past, and is just a different driving experience.
I don't try to pass on the highway any where near as much as I used to.
If there's really a need to pass, it's ussually not a problem, but definitely need to be more cautious.
I really don't know how anyone tolerates an auto trans in these though. The few I've driven have been underwhelming.
Thank you for this thread. I am at the 260K mark in my LX450s life. It has a smoking and leaking problem. Smokes when it starts up (valve seals) smokes when I put the beans to it on a hill (oil control rings) leaks out of many new places. People don't like driving behind me on trail rides. The truck marks it's territory after it sits for a minute. The bearings may be great, but if everything else is gone in the way of valve seals and oil control rings, it doesn't matter if your bearings and compression are great. It just starts to be too many strikes against the engine.
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It sounds like an engine you could potentially pull out, throw a gasket & seal kit in it, new bearings, new hoses and drop it back in.
If you have the capability, it's a couple of weekends to take care of it, & you'd potentially have change from $1000 bucks for small parts.
Mud has a combined obsession with "everything has to replace with new".
A quick refresh would see many of these engines good for another 200k
Ya a basic hone and fresh rings and bearings might be all it takes to get a 1fz several hundred thousand more miles.
if you bump up the pump pressure during a reflash or do a shift kit on a 4l60e it would last longer. The 4l60e internals can also be upgraded to 4l75e internals which is rated for quite a bit more power. I imagine my 4l60e will die some day. You can also use a nv4500 or a tremec.
NCFJ
Supporting Vendor
I installed a 6.0L with a Tremec 4050 5 speed behind it. Hands down my favorite truck to drive that I have built to date.
The 4L60E was upgraded to the 4L65E same case.
The 4L65E was upgraded to the 4L70E same case.
The 4L70E was upgraded to the 4L75E same case.
The case for these transmissions is smaller than the 4L80E and easier to fit in the tunnel.
IMHO putting any used trans in your LC with a swap and not having it rebuilt prior is foolish. Spend the money up front where it counts.
IMO, 4L80E first gear is not very great and 4L60E/70E/75E are hit and miss. Some guys can get 400K miles from one and others go through one every 30K miles. I don't know what makes the difference, but I am not one of the guys that has seen a long life from a GM automatic. I would lean towards one of the newer transmissions with many gears and better reliability.
80 series w/400HP 12 valve and NV4500 is the funnest vehicle I have ever driven.
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Personally, I am a bit leery about the reliability and longevity of the newer 8 and 10 speed transmissions and the cost of repairing one if or when it fails.
If I flipped vehicles every 2 years or 60,000 miles, I wouldn't care so much. Having blown transmissions in the past with overdrives, I am reluctant to go that route again without a really well-known and proven automatic.
CAFE/MPG factors for government compliance reasons have put a lot of questionable products and engineering into the public vehicle market IMHO.
I have a 4L80E behind the 5.9 12-valve Cummins in my 1.5 ton Chev 4x4. It's a pretty new build, so not sure how it's gonna work out.
If it doesn't hold up, i'll probably go to a HD Tremec 6-speed.
The most common problem with the 4l60e is the 3-4 clutch pack. It can (should) be upgraded with a Raybestos Z-Pac. Alto also makes upgrade kits. My daily driver 80 has the Alto 9 friction clutch pack, and the 80 swap that I’m finishing up uses the Z-Pac. The Alto tranny has a really hard 2-3 shift, the Z-Pac is much smoother, but noticeably firmer than stock. Beast sun shell is a must for earlier models, Sonix line pressure booster is a nice upgrade too. The 4l60e has a bad reputation, but they are cheap, compact, easy to work on, with lots of aftermarket support. Just my 2 cents.
