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1978 Crew Cab Build

25K views 139 replies 24 participants last post by  simplysmn 
#1 ·
I've been working on my crew cab for about 2 months now when I've had time. I've been meaning to start a build thread for a while so I'll get everything up to date today.

Here's how it sat when I picked it up. It had been sitting for around 7 years and the floor took a beating. After having a look at it I determined I'd only have to replace the front floor and i'd be on my way.

I got it home and gave it a good pressure wash


Started disassembling shortly after

Once the dash was removed I was able to have a closer look and realize the rust was worse than I thought. It had a bunch of pinholes along the front of the cab and also the cowls.

 
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#74 ·
Heck I pull most of my transmissions with just the floor jack and a piece of 2x6....to be honest a ratchet strap never even entered my mind as a possible assisting tool...:D

Have you decided on a colour yet? Looking good Dan!
 
#75 ·
The ratched strap worked great! A couple years ago I tried pulling it with the transfer case attached and just a floor jack.. It ended up upside down on the shop floor spewing the fluid everywhere.. :spank: I'd like to think I'm a little smarter now :smile2:

I'm kind of leaning towards something like this. Maybe a bit darker
 
#76 ·


I got home early from work for once and cleaned up some parts with the dinky electric pressure washer and degreaser.




It was a 2 man job but I rotated the engine over to remove the oil pan and have a look inside. The legs on the stand should be at least 12" longer on all ends.



Do any of you know if these are factory marks on the rod caps or from a rebuild? Is it normal to still be able to see those?




I also found some debris in the bottom of my oil pan. 2 somewhat large chunks of different material.. I can't quite tell what they're from yet.
 
#77 ·
The cast piece might be a piece of excess casting flashing that broke off after assembly? The other looks like a piece of amber...;)...but is it plastic?
 
#78 ·
I just broke it in half with my fingers so yeah definitely plastic lol.

I guess it was pretty clean in there for the mileage.

I'm thinking I'll just re-do the rear main seal and do the rear main gasket and oil pan gasket and bolt it back up.

My uncle keeps telling me "oh you better do the rod bearings in there!!"
 
#79 ·

It looks like I'll have to change the rear corssmembers if I want to use the 92 tank. I filled up the stock gas tank today and it only held 21 gallons :(

I've heard of people using the diesel tanks without a problem, I guess pre 1980 corssmembers are different in the rear :(
 
#80 ·
Can you tell what the differences are? Ahhh what's a few more cold rivets....;)
 
#81 ·
The crossmember on the 92 goes above the frame an extra couple inches and at a steeper angle to allow the tank to sit higher. Plus the frame is an inch taller so that helps too.

I heated the plastic up on the tank and re-shaped it to fit better. Still not sure if I like the way it sits.

Do you have any pictures in your build thread of when you installed your tank?
 
#82 ·
The one from the 93 fit fine....I just used the original 84 straps. But it already had the 89 1st Gen tank in it when I got it....so if there were any issues they were sorted out before I go it.
 
#83 ·
I got the axle and leaf springs cleaned up the other day



I remembered reading somewhere that our front axles are restricted for turning to the right because the drag link binds and won't push the wheels any further. Since I'm going with crossover steering I adjusted the bump stops for the knuckles and made the passenger side 1/4" shorter and the driver an entire inch. To find a safe turning radius I just kept turning the wheel with the hubs locked until I felt the ujoint start binding and then backed the bolt about 3/16 away from the stop.





Finally sitting on all 4s :) I have most of my brake lines bents too but didn't take any close pictures.

Also if anyone's noticed a drop in picture quality it's because I smashed my camera lens on my phone :doh:
 
#85 ·
I really would like to go with a reverse rotation steering system, but the bracket and pitman arm are tough to find. I don't really want to loose my front sway bar either....so the cross over steering is not as attractive as I would like.

Looking great Dan....only a 1000 more things to go...;) :D
 
#86 ·
I was talking to another member on here about front sway bars and he suggested making a bracket for the oem sway bar and orienting it like the 7.3 f250s.

It's something I'll consider if I don't like how the truck handles around corners. But our springs are pretty beefy so I don't think I'll notice much of a difference.

:laugh:Don't remind me how much more work there is to do, if I only think about a couple tasks at a time it won't get overwhelming ;)
 
#88 ·
Gets a little hard to focus on objects how I want too.. Not so HD anymore :(

I got tired of wasting time trying to think of a way to make my fuel tank work, or have my neighbor build me a custom aluminum tank. So I busted out the BFH and cold chisel and got to work for 30 minutes. 12 rivets later..

Before removing the crossmember:

After removing the crossmember:

Stock 20gallon tank:


Now I just have to do the same thing on my donor with the bed on :doh:


Also a guy from craigslist stopped by and bought my rear dana 60 for $125 :party018:
 
#92 ·
I fumbled around in the dark getting the crossmember off my donor truck to use over my fuel tank but old man rust had different plans for me. I will have to make my own crossmember or find one from a different truck. Unless I can use the crossmember without the lower frame supports or make my own just to bolt to the lower section of the frame. I'm not sure how I feel about not having those in right where the rear leaf spring perch is. I wouldn't want to cause the frame to twist while hauling heavy.





More brake lines bent and double flared.... Forgetting something??? :doh::hehe:

Disasembled the transmission and transfercase to find out what I need to order. Every bearing looked good! I'll need seal kits for both and a new 4th gear synchro for the getrag since that has been giving me issues about 5000kms after my rebuild. It was the only part I bought from a local shop and the rest was from Zumbrota Bearing and Gear :confused013:




The shift forks have some abnormal wear. I'll have to do some research about what's acceptable. It's hard to see in the picture but the middle shift fork is worn almost flat on the left side.



The dana 60 was in ok condition besides the split bushing. I'll be replacing the bearings, seals and upper kingpins since they have some slight pitting. I'm just waiting on my 7/8 hex socket to show up. Should be interesting removing them!
 
#93 ·
Getting some good progress....If those cones don't want to let go...and mine sure didn't...then cut about 1/8 up from the base of the cone all the way around....they will spin out almost by hand after that. ;)
 
#94 ·
Yup I already read through your tear down before I started :) I'll be doing that if my impact gun won't do it after putting the cones through some heat cycles.

I also used a variation of your ratchet strap method today


Worked great except for dropping it on my finger when it popped free..



The inner seals were put on with some sort of silicone. I was under the impression they were supposed to be installed dry?



The axle tubes were pretty nasty - glad most of that crap stayed out of the pumpkin.
 
#95 ·
Well the seals did there job then....keeping that rusty guff from your pumpkin. ;) Hope you have a big brass hammer, or brass drift to help get the carrier back in? At least I needed one.
 
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#96 ·
Everything looked good in the diff besides one tiny scuff on the carrier gear. Did 99.9% of it's job ;)
I have a pretty good size brass drift but i'll get a brass hammer if I have trouble getting it in :thumbsup:
 
#97 ·
I think it's about time I gave a small update. I've taken more time than i'd like off from working on my truck because of real work but I'm getting back into the swing of things now. I had some issues with parts and ordering but I've been getting parts slowly in the mail again and I'm back online ordering for the next wave of progress that needs to be done.

Once I cut around the kingpins they popped off without an issue with my impact gun.


I saw a guy on youtube using a hypodermic needle on an air grease-gun so I tried it out on my regular grease gun. Worked great for packing bearings. Little to no mess and it fills the bearing quickly and completely. Just shoot some grease between each roller bearing until it squishes out a bit and you're good.
Be very careful when handling it if you're going to try it out though... Slow movements :laugh:





Dana 60 all rebuilt, just needs to be filled with fluid. Also I got a new phone finally so pictures will be better quality again :)
 
#98 ·
I bought a fancy 40 gallon parts washer from princess auto so I put that to good use


Putting the getarag back together




I did the twin stick mod on one of the shift rails while it was out. Now I'll be able to use 2wd low when I'm stuck in bad traffic!


Everything looked good in the np205 but I rebuilt it anyways.

The main difference were the ball counts in the larger bearings. I wonder if more is better? :confused013:

I used a robertson screwdriver to put the roll pins back. The end fit snug into the roll pin and guided it in without an issue.

 
#99 ·
I put my seats in to get an idea of how I want to mount them and how much leg / head room I will have.



I have some ideas for the rear seats that will include a folding platform to create a flat space across the whole floor while the seats are folded up. Possibly a storage system tucked away in there too.

After inspecting the rear cross member I took out of my donor truck I determined it will be good to use after a wire wheel and paint. I made the holes larger in the frame and the cross member to use the same bolts I used for my 4x4 conversion. Everything lined up nicely after using a ratchet strap to suck the frame rails back together.

Now I will have to modify / make my own lower mounts to brace to lower part of the frame.

And that's all I have pictures of at the moment. I'm getting part numbers together to start re-sealing my engine and then painting it. I'm also trying to source out a local nv5600 for a reasonable price but I'm still having issues finding reliable sellers.
 
#101 ·
Looking great Dan.....can't wait to see it all done, will make patches look old and ratty next to it.....;)
 
#102 ·
Thanks Brian! That makes two of us ;) I'm sure they will compliment each other well when we have them parked side by side one day!


I found a local guy that is selling an nv5600 package from a wrecked 2003 truck with 220,000kms on it. Comes with the engine adapter, flywheel, clutch, transfer case, front driveshaft, hydraulics and shifter. Seems to be a decent deal for what he's asking considering I can sell the other parts I won't need. I'll have a look at it sometime next week. Does anyone know of a way to check the transmission out besides just spinning it over by hand and shifting through the gears? There's no easy way to look at the internals before purchasing that I'm aware of.
 
#103 ·
From what I have read, and seen here on the boards the NV5600 is almost impossible to diagnoses the bearings without a total tear down. The bearing condition, and the condition of the case in those areas can dictate if the tranny is any good or not for rebuilding.
 
#104 ·
That's what I thought. Concerns me a bit when dropping that kind of money on an unknown condition transmission. All he can tell me is he test drove it in 1st and 2nd but the truck was in a front end collision so he couldn't steer it much around the yard. He makes a living buying and selling salvage parts.
 
#105 ·
I'd be leary too about dropping big $$$ on a NV5600 6spd tranny and have it be junk. One of the biggest reasons I will stay with my NV4500...or if I had one, Getrag. If I was pulling all the time, and really needed the closer gear ratios then perhaps, but does a 6spd conversion, and the end product justify the added expense?

I think the G56, ZF6 has more support, and rebuild options then the now pretty much obsolete NV5600.
 
#107 ·
Does any of this justify the extra time and expense? Of course! :grin2:

I've taken a long time to decide between the 6spds and although i'd prefer the zf6 out of the 3 the extra expense of getting an adapter and trying to figure out how to use my np205 with it turned me away. Not to mention the starter is on the passenger side where the exhaust is.

The g56 just seems too weak compared to the nv5600 from what I've read. My buddy has a 2008 6.7 and he has gone through 4 g56s in the last couple years. Yes he tows quite heavy but he hates how it shifts too.

I agree rebuild options are pretty scarce for the n5600 though. It seems the rebuild parts floating around for sale aren't of the same oem quality. Maybe I should just get a new Aisin with an electronic controller :hehe:


Nice build, I'd love to have a crew cab some day but Ohio rust killed off most of these trucks years ago.

If you still haven't decided on a color, the bronze/red color on my old 92 would look good with those tan seats and it's an OEM option so it would look era appropriate..

Mopar data is DT3519, PVB Dark Copper Metallic



101_0704.jpg Photo by Grasshopper2276 | Photobucket

Thanks :)

That is a nice era appropriate colour. Very close to Stu91s truck.
 
#106 ·
Nice build, I'd love to have a crew cab some day but Ohio rust killed off most of these trucks years ago.

If you still haven't decided on a color, the bronze/red color on my old 92 would look good with those tan seats and it's an OEM option so it would look era appropriate..

Mopar data is DT3519, PVB Dark Copper Metallic



101_0704.jpg Photo by Grasshopper2276 | Photobucket

 
#108 ·
Or you could save money and get a gear vendor unit for the back of the transfer case....you'd have a 10 spd then. If I was to ever want to upgrade from my NV4500 I think this is the route I would go.
 
#109 ·
I had that in mind as well originally but I don't like the idea of a gear vendors unit behind my getrag that could fail. Plus I have an exhaust brake which I used all the time and the gear vendor units don't last when used with one. I think it's fine if you remember to not have it engaged when the exhaust brake is activated but it just seems like another thing to worry about going wrong. If US gear still made their overdrive units that went in front of the trasfer case that would be a nice option.

IMO an nv5600 in good condition will be more reliable and hold up to more stress than my g360 with a gear vendors behind it. The g360 is a good transmission but the nv5600 is a little more bulletproof for my intended uses. A .73 overdrive ratio should be plenty for me as well if I'm going with 33" tires. Should be 1800rpm at 110kmh in 6th.
 
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