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Once a Postal 67 800 Build

I'd pull the radiator and cap one outlet and make a small rig to pressurize the other, then find the leak woth soapy water and evaluate if it can be welded or brazed.
The leak is in the middle of the core, and looks like it is towards the middle. Shining a light at it you can see the coolant in the fins. I will have to check further, but it looks like I cannot weld or braze it. It barely leaks, just a few drips on the ground after a long drive, but I do not want the radiator to build pressure and blow the hole even bigger.
 
Put on the new springs. Sits at 6 inches of uptravel with 23 inches under the frame rails on 37's.
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The suspension is super soft. I can take one hand and shove down a corner 3-4 inches lol. I will probably need a swaybar in the rear, the radius arms in the front should add some stability. We will see one i get to take it for a ride tommarrow. Never driven something like this, so it will be interesting.
 
Transmission was having an issue with the shifter, so I took off the shifter to see if there was anything wrong with it. Dropped a bolt into the transmission by accident. Going to be pulling the transmission again.
 
Figured since I pulled the tranny why not stare at this thing in my garage for a few more months. Pulled one of the other np241s off my shelf to turn it into a doubler.
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Cut the case, and put it back together. Just need to get some aluminum to build a cap for it and some steel to build the adapter plate to the other transfer case. Also looking for someone that can spline the shaft. I have access to a lathe teaching the old mainshaft to the size I want, just having trouble trying to find someone to spline the end of it to go in the other case.
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Had some other issues with the transmission, mainly that first gear was simply missing. Was able to source another transmission, although this one has an internal slave. Looks like they use the same master, so I just need a new hardline and slave. Also decided to bring out my inner overlander mall crawler and flex the scout out on stacking stones in my yard.

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The radius arms do bind up, but removing one made the suspension feel much more balanced, and it flexed evenly. Driving on the street with one arm disconnected did not feel different at all, although it did lean more around corners. Kind of why I chose them over 3 link as they would act as links and swaybar in one. It does feel squirrelly over 15 mph though, and tries to dart off to the driver side when you punch it. Will have to check toe in but otherwise it drives good on the street. Needs a windshield, some fender clearancing, and new transmission and I can finally wheel this thing.
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Was just watching Ian Johnson do a radius arm on that Colorado. Used this radius kit that has a shock/spring set up on one of the upper arms that allows it to not bind and still move freely. Was interesting.
 
Was just watching Ian Johnson do a radius arm on that Colorado. Used this radius kit that has a shock/spring set up on one of the upper arms that allows it to not bind and still move freely. Was interesting.
Was thinking about the shock for one of the links setup. You valve it so it only let's it move at slow speeds and it locks up at high speeds like a swaybar. Carli sells a similar setup for their Ford and dodge kits, seems to work well.
 
Went ahead and swapped the transmission. It now has a working 1st gear. I am still chasing some drivability issues, I have aligned the front and rear axles. They are square to each other and in line with one another. I have the toe set to be an 1/8 inch toed in, and caster is at about 6-8 degrees. It drives alright, but as soon as you accelerate it pulls very hard to the left, and when you let off the pedal or shift it pulls hard to the right. I have very little bump steer since my pan hard is only a half inch longer than my drag link and they are only off from one another a couple degrees. I figured this is a geometry issue amplified by the soft suspension. By researching old threads on the other site this sounds like I have lots of over steer, since the truck is being torqued over and causing the rear end to steer under acceleration. Still trying to figure this out, but if anyone has any suggestions I would appreciate it.
 
Does it pull the wheel in your hands, or is it all in the chassis? If it's pulling the wheel, play with more toe (try 1/4" or less toe 1/16") - that's free at least to try.

If the wheel isn't turning, I'd look at the rear end more. rear locker is an auto-locker or spool? rear sway bar?
 
Does it pull the wheel in your hands, or is it all in the chassis? If it's pulling the wheel, play with more toe (try 1/4" or less toe 1/16") - that's free at least to try.

If the wheel isn't turning, I'd look at the rear end more. rear locker is an auto-locker or spool? rear sway bar?
Pull is in the chassis, the wheel does not pull at all really it just kind of shoots off to the left. Currently the factory gm gov lock (doubt it does anything) I have not put in a rear sway bar yet.
 
Pull is in the chassis, the wheel does not pull at all really it just kind of shoots off to the left. Currently the factory gm gov lock (doubt it does anything) I have not put in a rear sway bar yet.
I think the Gov Lock behaves like a Detroit (autolocker). I had very similar experience with a manual and a Detroit in the rear axle.

Gravel roads at speed were a whole new experience with that setup. I think the automatic transmissions keep the auto lockers loaded, and "tame" them a bit.

Was an ARB in your plans? id wager that fixes it right up.

What does it do on loose gravel roads?
 
Also, if you put it in rear only and load the suspension (let the clutch out and get on the brakes, don't stall it, but give some resistance) - does the rear end stand up, sit down, or remain the same?
 
Also, if you put it in rear only and load the suspension (let the clutch out and get on the brakes, don't stall it, but give some resistance) - does the rear end stand up, sit down, or remain the same?
Put it in low range and left the hubs unlocked. Let the clutch out in first, and it lifted up the rear end significantly, with a lot of bias to the drivers side. Doing the same thing in reverse lowered the rear end with bias to the drivers side.
 
I cut the links and threw them on the truck in order to start having fun and flexing the rear axle.
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Sounds like a higher anti-squat - definitely work to do with the rear suspension.

Looks like you can try a different hole location in your upper links for free to see if it gets better. if you're in the lowest hole, that will make the highest anti-squat with the furthest aft instant center. I'd try the middle hole - because it's free to try, should lower the anti squat a little and move the instant center forward.

And the bias side to side can be tamed a bit with a swaybar.
 
Sounds like a higher anti-squat - definitely work to do with the rear suspension.

Looks like you can try a different hole location in your upper links for free to see if it gets better. if you're in the lowest hole, that will make the highest anti-squat with the furthest aft instant center. I'd try the middle hole - because it's free to try, should lower the anti squat a little and move the instant center forward.

And the bias side to side can be tamed a bit with a swaybar.
Thanks for the advice. I will try this and report back to see if it helps my issue. I will need to get a sway bar, it is pretty stable around turns at speed, but will definitely need something to keep the rear in check while wheeling.
 
Thanks for the advice. I will try this and report back to see if it helps my issue. I will need to get a sway bar, it is pretty stable around turns at speed, but will definitely need something to keep the rear in check while wheeling.
Update: helped a lot, this thing is way more manageable. Had it floored shifting up to about 50 and it tracked way better. Still pulls a little but more more predictable. I will put a swaybar in the rear, and that should help out more with it feeling stable.
 
Cut up the front fenders so the tires could flex out. Front came out pretty nice, Should allow the 37s to flex and turn.

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Also put in a windshield, and got it registered. It is now tagged and street legal. License plate says last time it was registered was in 2005. It drives like shit on the highway though. It takes a ton of effort to keep it in a lane, and it likes to try and switch lanes. I will get some proper alignment tools to align this thing properly, and also I need to check the charge on the shocks, not sure if they were charged properly. Oh yeah it also lost the clutch today, was at a stoplight and when I hit the clutch it fell on the floor and dumped all the fluid onto the street. Was able to get it off the highway and take side roads back home by starting it in gear and floating through the gears. Looks like I had a bad o-ring on the slave side. Will pull the tranny and fix that, internal slaves are a bitch. I am getting good at pulling the transmission on this, can do it within an hour now. Was planning on wheeling this weekend, but will properly postpone it to fix all my issues.
 
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Figured out the clutch hydraulic line I had put in had blown out the area around the crimp for the fitting. Since it is an internal slave you cannot easily get to the fitting easily with a wrench, so I drilled out one end of a socket and welded it to the end of a pipe. I can now slide it down the line to take it off.
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I also invested in one of these lazers to check my alignment no wonder it drives like shit nothing is square and the axles are offset from each other about an inch. It looked accurate with plumbobs and a tape measure, will fully align the rest of the truck and it should drive a whole lot better.
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Been mainly driving it, with a little work here and there. Got the clutch working again, and spent some time aligning it properly. It still drives pretty shit, does not feel stable at speed and is a handful to keep in a lane. It drives worse than my TTB f250 with worn out steering. Hoping to get those issues figured out since I love driving this thing around town, and I want to be able to take it on the freeway to get to trails. (Nearest trails are 2 hours away). I also spent some time adding gussets to the cage. Going to add these around the entire cage, it will make me feel much better.
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Hoping to get out on the trails soon. Will also need to learn to valve shocks. The stock valving is pretty stiff, hitting speed bumps at the mall with any kind of speed wants to kill your kidneys. Might also look into trailing arms for the rear since the tire tends to rub the coil over pretty bad at full flex. The trailing arms will put the shocks in a much better spot since I have the room where the stock gas tanks used to go.
 
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Got it out of the shop and hauled it up to big bear.
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Next to my buddies blazer. He dropped in a "bulletproofed" and freshly rebuilt 6.2 turbo diesel along with a 4l80E recently. Told him to cummins swap it but oh well. Still pretty wimpy on stock axles and 33's.
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Old wheeling rig hauling the new one. The poor 351w in that truck has about 350k on it and barely got the scout down the freeway at 50. Hopefully will get the other f250 I have going so i can have a tow rig with a big block.
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Ran great, did not break anything. Not too many rocks, but it was cold with lots of powder from the last snowstorm. Never wheeled in actual snow before, was fun. Also was a ton of mud, not a big fan of mud (too many bad experiences with destroyed wheel bearings). Tried tried to get up into some Boulder fields but with open diffs and all the ice that was not happening.

Stuff I learned.
1. Needs lockers
2. Needs a heater
3. Desperately needs shocks to be tuned. Way too stiff. Rides worse than the f250 which is saying something
4. Needs a rear swaybar too much body roll around turns, and sways too much at speed.
5. More gearing. Time to finish that doubler box project and regear the axles.
 
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