CK5
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1973 C10 "The Purple Truck"

Basic build
Some 3.73 and that trans would be a good 2WD combo for you.
The more I drive, it the more I realize gears will have to happen sooner than I'd thought. What I've done for now to compensate is adjust the transmission programming to raise the shift speeds up a lot. Currently it'll hold 2nd gear to about 35 and 3rd gear to 55. It actually works pretty good in conjunction with the TCC speed setting. If I'm cruising at 35mph it will be in 2nd gear but with the TCC engaged so the RPM is staying down.

It's like the opposite of my 66 with the SM420 and 4.57 gears where I'm pretty much driving in 4th gear all the time. Hell, it's not even impossible to start the truck rolling in 4th.

3.73 is what I was thinking. It will require a new carrier, so I'm thinking I'll put a LSD in while I'm at it. I've also been keeping an eye out for a donor axle, but 12 bolt truck axles don't come up as frequently as they used to. Or a 10blt with 5 on 5 wheel pattern.
 
Almost forgot to add, the higher stall converter did solve one problem I've had since installing the PF4. The engine does not stall when I shift it into gear at any time. For as long as I've had the PF4, it has stalled when shifting into gear until the engine is fully warmed up.

Also, I do still need to work on the parking brake. As you all said, it doesn't function properly. I'm glad I have the newer 4l80 with the better parking pawl; it feels sturdy when I put it in park on the angled driveway.
 
I salvaged the factory trans cooler from the parts truck along with the 4l80 because it was a nice stacked plate cooler. Turns out as much as I've grown to like the 73 grille, it makes it extremely difficult to fit a trans cooler because the grille is so thick/recessed. The AC condenser is also taking up lots of room. I had hoped to put a fan on it, but that's definitely not happening. Hopefully it'll be fine without or I'm going to have to come up with a creative mounting location.

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That is the only orientation the cooler would fit. It's about an 1/8" of inch from the condenser at the bottom. The grille angles back and gets closer to the condenser as you move away from the center so the cooler is too wide to fit with the fittings pointed down.

Don't worry, I wasn't going to leave all that shiny aluminum and screw heads standing out looking thru the grille.

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Didn't have time to do the plumbing so that will come next week.
 
I have not needed a separate fan when placed in front of the engine radiator/fan like you did yourself.
 
You shouldn't have to worry about a fan. Since it's a 2wd, the vehicle speed should take care of it. Unless you start crawling with it!
There have been several times I've needed to remind myself I'm not building a crawler.

Nate was helping me finish up the trans install and he put the crossmember bolts in with the nuts on the bottom of the frame. My first reaction was "I'm going to be hitting those all the time!". Then I remembered it's not a rock crawler. :doah: His logic was that if the nuts came off, the bolts were still holding the crossmember in place.
 
There have been several times I've needed to remind myself I'm not building a crawler.

Nate was helping me finish up the trans install and he put the crossmember bolts in with the nuts on the bottom of the frame. My first reaction was "I'm going to be hitting those all the time!". Then I remembered it's not a rock crawler. :doah: His logic was that if the nuts came off, the bolts were still holding the crossmember in place.
I run all bolts downhill if I can, for that exact reason. Gravity.
 
I forgot to mention what I found for the fittings on the factory cooler. I threaded the oring clip style fittings out and found they are 3/8 npt. Luckily I had a couple of 3/8 npt to -6 an adapters in my cache of fittings.

Finished up the install yesterday. I would have liked to use the black nylon braided lines so they didn't standout behind the grill, but I had some stainless braided left over from other projects.

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I used 2 different adapters to plumb the cooler into the factory lines. There is a -6an to 1/2-20 inverted flare adapter in the radiator and a -6an to 5/16" tubing compression fitting adapter on the factory hard line.

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Normally I use Russell, Earls, or Vibrant fittings but it only occurred to me a couple of days ago that an adapter might exist for AN to inverted flare and getting a next day order from the jungle company fit my timeline. https://www.amazon.com/gp/aw/d/B09ZP21NXQ?psc=1&ref=ppx_pop_mob_b_asin_title

This is the compression fitting adapter I used for the hardline. https://www.summitracing.com/parts/VPE-16455 I've used these fittings several time for trans coolers and fuel lines and they work well.

I did cheap out on the cutters for the braided line. The jungle company had these Vibrant cutters for just about $62. https://www.amazon.com/gp/aw/d/B00QF3PX2G?psc=1&ref=ppx_pop_mob_b_asin_title

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They worked great.

You can a similar cutter from Harbor Freight for about $25, but there were a few reviews that said they didn't work well for steel braided hose. I opted to get a little better quality with the Vibrant cutters.
 
I snapped a picture of how I had to mount the dipstick tube for the 4l80. A little shadetree, but it works.

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This is the solution I have to make the parking brake work around the 4l80 pan.

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It's a loop of steel strap that came off the Skylark when we swapped the intake. Like @Capt Ron suggested, I threaded out on the adjuster to get the slack right with the added steel loop. That loop is pretty stout, but over time it will get bent down and not work like it should. It's mostly a proof of concept.

The long term solution I've come up with is to drill holes in each side of the trans mount plate. I'll source 2 of the rods that hold the cable down the frame.

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Not sure if the length will be right to put them directly in the holes. If not, I'm thinking I'll weld the rods to a couple of bolt heads. With a guide on each side of the trans mount plate, it'll keep the cable out of the pan when the brake is set. I'm fortunate the adjuster has tons of room to let out more slack.

Not going to be able to test out the trans cooler today.

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Right now the 66 C20 and mom's car are in the garage. We wanted to do the 3 car garage but our side setbacks were about 2ft too close due to a utility easement. In the middle of construction, they ended up abandoning the easement, too late to get our 3 car garage.
 
I forgot to add that I got rid of my vapor canister. In looking for valve cover grommets I was looking at the PCV and how it's plumbed in to the EFI. From the factory the PCV line is teed in with a line to the vapor canister. There is a smaller vacuum line from the throttle body to the purge valve on the vapor canister which I have teed to the vacuum referenced pressure regulator.

I figured out that normally the purge valve is connected to ported vacuum on the carburetor. It occurred to me that if my line is teed in to the vacuum referenced fuel regulator, it must be on manifold vacuum. So I've been running with the purge valve open all the time, particularly at idle. The PF4 does not have a ported vacuum port, so I decided to just eliminate the vapor canister.
 
I run all bolts downhill if I can, for that exact reason. Gravity.

Next time your under a steel bridge with bolted splice plates look at the bolts.
The bolts should be upside down.

Thought here is that if a splice plate connection comes loose and bolts rattle out that the bolt laying on the underpass will be more noticeable then some random nut.

Since bolting works on tension, by the time a bolt lands the bridge is technically already compromised. So the bolt still being there would be of no matter if it was stuffed from the top.


(Note: not all bridges in all states may be like this.
But with the new bridges I build at my current location that is the thought process. )

Just thought you might find that interesting...

....now back you your normally scheduled trans cooler tech....
 
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