Build 1970 FatherSonJ40 project

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Absolutely fantastic trip this weekend. Truly years in the making, where do I even start?!

The truck/tow setup worked fantastic. Rolled across the scales at a bit over 16k, and the mighty Cummins pulled it like a champ. The 40 tracked wonderfully even a few times when I hit 75 on accident. I hit the brakes really hard once and they seemed to work quite nicely through the tow bar brake setup. 4 locking hubs is the prefect setup for flat towing. I have the steering wheel strapped to the seat frame, and it certainly is working well, but wondering if I should allow a little more play?

The 40- this was my first real taste of true off roading in this thing and I'm staggered. It will go anywhere, with ease. Locked, 33s down to about 12psi, and in 4 low, it was unstoppable. And surprisingly comfortable. It was so apparent this is the natural habitat of the FJ40- off-road at 15 mph or less. Some commentary and improvements desired:

- I'm very much looking forward to the new transmission still, as (not sure if I've ever mentioned this) but I hate this damn 3 Spd. Needing to shift down to first at times is such a pain on the trail when it either grinds and won't go in, or you have to double clutch and bump second. Can't wait for the even lower H55f first gear. 1st 4low still isn't quite enough sometimes.

- I definitely need some soft doors. It started snowing one day and everyone really wanted the heat! (which also means I need to get the heater back in as well). Maybe ill just get some of the best top ones and keep them under the back seat.

- I have a wheel bearing or sticking caliper somewhere. I'm getting an awful groan that is certainly rotational, and seems to appear once things are warm. Jabbing the brakes can sometimes make it go away immediately. Its definitely wheel bearing out though, as I could hear it when we left camp, so all four hubs were unlocked and things were still warm, but it was behind the truck so no drivetrain was spinning.

- Rear springs appear to have about had it. We were hitting the bumps a lot in the rear and it's squatting noticebly. The shackle angle on the drivers side looks about maxed out at rest.

- The motor is running fantastic. My stupid high dollar duralast AGM is not holding a charge well, but once it's charged up, the motor really sings. It will make someone a nice runner in a few months when I swap it. But mercy its thirsty. I think we did around 60 miles on a half a tank (granted all between 9,000 and nearly 12,000 ft), so under 6-7 mpg.... This isn't a big concern for me, as I don't drive this thing enough for it to make a dent in my wallet, but dang, that go FAST when you're far away from a gas station! If the 12HT doubles that, it'd be a game changer.

- My front axle may be bent? Both of my front wheels are showing some noticeable camber...

My boys and wife had a blast, the fall colors were absolutely off the charts, and perhaps most importantly, my wife loved it, waxing nostalgic for bumping around her great grandparents farm in rural Maine with her dad in an ancient CJ3 Jeep. We're all hooked! Even my old dog had plenty of space to take a nap!

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Just bought the project I've dreamed about for years. 1970 FJ40. Has the original 1F w/ Holley EFI and a 3spd converted to floor shift. 33s and what looks like 2in OME lift. The body and frame are in decent shape, though I've got a few different colors on the outside. Most stuff works.

I've wanted one of these forever and have come close a few times but it never made sense or was the correct one. When I was a kid, my dad bought his dream classic- 1970 El Camino SS that we redid top to bottom and he still drives all the time. It was the greatest father son experience a car crazy kid could ask for. Since I've had a 98 chevy 6.5 I covered to WVO, a 1984 W350 I but a 6bt, NV4500 etc in, and most recently an 05 Ram 2500 cummins I did a ton of work to. I'm a decent shade tree mechanic and fabricator and want to share that experience with my son and the one coming in January. I've got a workshop full of tools that will likely be rebuilt in the next couple of years so we'll have a good place to work. I find I have more bucks than time these days, so might be farming out the first few projects and things till the boys are old enough to join in. Can't wait for the adventure! Plus my wife loves it!

Plan is to add power steering and a full cage and drive it for a while. Headed to Redline in December to get those two things taken care of. I have a 4spd I may have put in too to improve drivability some. We have a slide in camper for my Ram, so also plan to set it up for flat towing and have it tag along on some camping trips. Eventually would love to do full paint and body and a tasteful diesel swap. Thinking a 1KZT driveline, but other wise want to keep fairly original. I'll update with progress and ask many many questions.

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Looks like nice solid start!
 
Getting some things cleaned up on the 12HT and really would like to paint the crossover tubes that say “Toyota and Turbo”. Anybody have any suggestions for a high temp rated paint that I could brush in there? I could always buy spray paint and spend a bunch of time masking but would prefer something brushable.

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Replaced rear main seal and pilot bearing, as trans/transfer combo is on the way back from valley hybrids. Man Georg is so awesome to work with. Ended up doing a full transfer case rebuild, but apparently the trans looked brand new inside, so just a reseal.

Cleaned, blasted and VHT coated my heat shields and they look frankly too good for a motor. I scrubbed and ultra sonic cleaned the crossover tubes as much as my patience allowed. They’re far from perfect, but still look decent. Keep telling myself it’s a motor that is going to get instantly dirty…

12v alternator and starter have been ordered. They all seem to be in Australia and damn if the tariff situation hasn’t made that wildly more expensive and more difficult.

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I’m back to work on this swap after getting my Alfa running again only to promptly blow the head gasket. Uhg!

Alternator and starter have been located and finally arrived. I got the alternator swapped out today, as well and fabbed up the drivers side engine mount. I ended up grafting the power steering ear from the HJ61 mount onto the HJ47 mount, though I’ll say even without the ear connecting the power steering pump to the motor mount, the power steering pump is still very very solid, so not sure it was totally necessary.

I waited forever to get a set of engine isolators from Australia and they don’t have the locating pin in the right position. It appears Terrain tamer now has the correct isolators, but they’re $93 each. How important do we think those are? I’m tempted to just grind them off…

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Absolutely fantastic trip this weekend. Truly years in the making, where do I even start?!

The truck/tow setup worked fantastic. Rolled across the scales at a bit over 16k, and the mighty Cummins pulled it like a champ. The 40 tracked wonderfully even a few times when I hit 75 on accident. I hit the brakes really hard once and they seemed to work quite nicely through the tow bar brake setup. 4 locking hubs is the prefect setup for flat towing. I have the steering wheel strapped to the seat frame, and it certainly is working well, but wondering if I should allow a little more play?

The 40- this was my first real taste of true off roading in this thing and I'm staggered. It will go anywhere, with ease. Locked, 33s down to about 12psi, and in 4 low, it was unstoppable. And surprisingly comfortable. It was so apparent this is the natural habitat of the FJ40- off-road at 15 mph or less. Some commentary and improvements desired:

- I'm very much looking forward to the new transmission still, as (not sure if I've ever mentioned this) but I hate this damn 3 Spd. Needing to shift down to first at times is such a pain on the trail when it either grinds and won't go in, or you have to double clutch and bump second. Can't wait for the even lower H55f first gear. 1st 4low still isn't quite enough sometimes.

- I definitely need some soft doors. It started snowing one day and everyone really wanted the heat! (which also means I need to get the heater back in as well). Maybe ill just get some of the best top ones and keep them under the back seat.

- I have a wheel bearing or sticking caliper somewhere. I'm getting an awful groan that is certainly rotational, and seems to appear once things are warm. Jabbing the brakes can sometimes make it go away immediately. Its definitely wheel bearing out though, as I could hear it when we left camp, so all four hubs were unlocked and things were still warm, but it was behind the truck so no drivetrain was spinning.

- Rear springs appear to have about had it. We were hitting the bumps a lot in the rear and it's squatting noticebly. The shackle angle on the drivers side looks about maxed out at rest.

- The motor is running fantastic. My stupid high dollar duralast AGM is not holding a charge well, but once it's charged up, the motor really sings. It will make someone a nice runner in a few months when I swap it. But mercy its thirsty. I think we did around 60 miles on a half a tank (granted all between 9,000 and nearly 12,000 ft), so under 6-7 mpg.... This isn't a big concern for me, as I don't drive this thing enough for it to make a dent in my wallet, but dang, that go FAST when you're far away from a gas station! If the 12HT doubles that, it'd be a game changer.

- My front axle may be bent? Both of my front wheels are showing some noticeable camber...

My boys and wife had a blast, the fall colors were absolutely off the charts, and perhaps most importantly, my wife loved it, waxing nostalgic for bumping around her great grandparents farm in rural Maine with her dad in an ancient CJ3 Jeep. We're all hooked! Even my old dog had plenty of space to take a nap!

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This is really cool to see! I am about to take our family on a West coast trip and up through a few of the parks this coming summer.

I have a question regarding towing the 40 as we would be doing the same behind our RV (not camper). What tow bar are you using (or recommend) and did you end up leaving more space for the wheel to move around or strap it pretty tight for not so much movement? Anything I should watch out for prior to towing the 40?
 
This is really cool to see! I am about to take our family on a West coast trip and up through a few of the parks this coming summer.

I have a question regarding towing the 40 as we would be doing the same behind our RV (not camper). What tow bar are you using (or recommend) and did you end up leaving more space for the wheel to move around or strap it pretty tight for not so much movement? Anything I should watch out for prior to towing the 40?
I have an NSA products tow bar/brake combo. it uses a cable attached to your brake pedal- Ready Brute Elite II RV Tow Bar With Integrated Supplemental Brake - https://nsarvproducts.com/collections/built-in-braking-system/products/rv-tow-bar-ready-brute-elite-ii

I highly recommend it, granted I've never used anything else. Definitely pricy, but compared to the other brake setups, it was actually more affordable. It really wasn't too bad to get setup, and once installed, it's an easy hookup. The tow bar itself is seriously beefy. I wouldn't want to tow without a brake, though I know plenty of people do.

I tied my steering wheel pretty tightly to the seat base, so the wheel didn't move much. Next time I'll likely give it a bit more slack. I noticed a bit of "scrub wear" on my front tires, so will try and alleviate some of that. If it's aligned well, I've heard it will do great without being tied down, but I've never tried. I'm probably going to look for some sort of windshield cover/protector also. Got a rock chip on the last trip.

Other than that, just go slow and swing wide!
 
Gave the 40 a little love today- used the Bob smith adhesive and activator that cruiser corp sells and installed new door seals and put the doors back on. The tan one matches my top actually very closely.

I also have the Nomad wheels and Falken tires on my 45 right now. Man the 14 year old BFGs feel scary in comparison. The wheels are 15x6? It needs new tires, so I’m leaning words the Kenda Klever RT in 33x9.5r15. Seems to get good reviews and I’d really rather not buy another set of wheels too. Though I gotta say, the wagon wheels on the 40 look very “jeep” and can’t say I care for it!

In case anyone is looking for a shot of the length difference between a 45 and a 40…

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Gave the 40 some more love today- new tires! its crazy to me how much of a difference new and balanced tires can make. Visually the BFGs were barely worn, but the were Feb 2012 tires, so long over due. There really is breakdown you can't see!

I went with a set of the Kenda Klever 601 r/t in 33x9.5r15. they look excellent and run as smooth as glass. Had them mounted up at Nomad Cruisers, which is a relatively new shop here in Colorado Springs. They did an excellent job and got me wrapped up in less than 24 hours.

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The 40 is going to get some serious love here at the end of the week while I plug along on the 12HT swap on the troopy. I’m farming the job out to a local shop, but it’s getting the H55f and splitcase that I just had redone by valley hybrids. They’re going to do a custom cross member similar to the 4plus one that also integrates a skid plate covering the whole drivetrain. Can’t wait!

And couldn’t come soon enough. I drive it to the parts store the other day and it’s deafening. The gear howl is outrageous and there are multiple bearing squeals that make it sound like it’s going to come apart. The splitcase and h41 in my troopy is utterly silent in comparison.
 
Dropped off the 40 yesterday chock full of parts to get the transmission swap done at a local shop. I’m so excited! Can’t wait to have a new, better, quiet, more capable, better spaced gear box!

It’ll be a race to see who can finish up faster, this shop, or me on my 12HT swap in my 45.
 
Stopped into the shop to check on things today and pickup driveshafts to be altered. Man, the flywheel on my old 3 speed was absolutely toast. it had about 100 heat cracks radiating out from the center. No wonder it sucked so bad to drive! They're thinking it should be wrapped up by the end of this week or early next week. Man I can't wait!
 
Big bummer today. After a number of setbacks, the shop got everything installed and the skid plate finalized. It looks bomber. However, on the initial shake down drive, went back up on the lift to do some adjusting to the clutch slave. Oil was running out of the front of the transmission. Looks like the transfer is filling the transmission and it’s leaking out the input seal. I’m sure everyone involved will take care of it, but what a bummer. Was supposed to drive it home today.

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Whelp, it’s finally back! And h55f/splitcase equipped!

Haven’t driven a ton yet, but initial impressions are mixed. The old “replace the clutch master and slave together” appears to be true as my clutch just doesn’t feel right. It’s all the way to the floor to get it to disengage and really mushy up top. Old master with brand new slave appears to be the culprit.

The quality of work appears ok, no real complaints there. The transmission does shift pretty hard though. I’m hoping that being brand new, it just needs time to wear in. Or maybe the truth is the H41 I’ve been driving in my 45 is just the sweet spot. I am surprised at how loud everything is though. I do have a missing shifter boot and thus an open hole in the floor, so I know that will have a big difference. I guess the sound deadening done in my 45 really has made a difference. It’s definitely calling for a quieter muffler too.

Engine wise, man, I’m just ruined after some real seat time in my 45 with the 12HT. There’s just no comparison. Honestly the overdrive with the 1F is almost a waste, it will just almost never see 5th… I guess it’ll just have to get a new motor too…

The super super short rear driveshaft, definitely has some vibrations at 2,500+. Maybe need to look at a DC joint on one end, haven’t really looked at angles, but I’m sure they’re not good. I can say though, it’s great to have a parking brake that works though!

Anyways, not sure what the future holds for this one, despite just spending a fortune on it. It’s just so apparent that my 45 is so much sweeter to drive, and is going to really be hard to pick the keys for this one. That being said, my 45 should largely be “done” soon, and I’m sure I’ll get the itch for a major project soon enough. I’ve got a cover and an outside parking spot available for this, so no need to make any huge decisions anytime soon.

Anyways, time to update the signature and get this on some dirt soon!

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Drove around a little more today. The transmission is loosening up a little with some use.

My rear brakes are still dragging and making a horrible noise. I don’t think it’s a sticking caliper, but could be. I think the big problem is the rotors aren’t centered in the caliper, so the outside brake pad is resting against the outside at all times in probably too much of a pressure situation. I kind of think the caliper brackets might be on the wrong sides of the axle…

Driving it so close to my 45 with the 12HT is just ruinous. It’d be so more more enjoyable with 25 more HP. I’m assuming my 1F is probably 90hp or so? I know I’d be a whole lot more likely to drive it with a better motor. I could rebuild the 2F sitting in my shop with performance in mind, or the more likely candidate, a 1HZ or 1HDT… probably be fairly even money for what I see a higher HP 2F rebuild go for, doing as much as I could myself. Or paying it out, save a ton going diesel. Who am I kidding, I want the diesel!
 
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