Big John: 1972 C30 2WD dually w/ 11' dump bed

Well...I might have a Detroit for it!
 
As said above 67-72chevytrucks.com will be your friend, although I believe I have seen an HO72/52 for sale here once or twice.

The third member / hogs head from a 3/4t (HO52) and a 1t+ (HO72) will both fit in your axle. HO72 is suppose to have a load bolt on the drivers side of the hogs head to put load against the ring gear.

If you have had surgery on that left knee already, I would definitely recommend looking into a hyd. clutch, that truck probably has either an 11 or 12" clutch, with a VERY heavy pressure plate, being as tall as you are in a regular cab, the ergonomics are going to be even worse (you almost end up pivoting at your hip with your knee bent).
Good info, I plan on working on it again in a couple of weeks so I'll get some more info then (and hopefully fire it up). I was hoping to lower the seat 1-2" to get some more headroom/legroom, but that may make shifting a pain

Well...I might have a Detroit for it!
Depending on what I find out, we may work out a deal!
 
Well, I got it running over the weekend!


Pulled all the plugs Saturday morning before going to a get together at the lake and added some Marvel's to the cylinders as well as what I could reach in the valve covers to let everything soak. Came back after lunch, pulled the plugs again and rotated the engine by hand ~10 times after checking all the fluids were there. Hooked up a battery and turned it over while checking for oil pressure (2/3 to 5/8 on the gauge). Emptied the boat fuel tank, added some new fuel, primed it and then got my dad to watch to make sure nothing leaked or went wrong. We put all the plugs & wires back on, poured some gas down the carb and turned the key. Took a few times (I flooded it once), but he finally came to life and proceeded to fog for mosquitoes for 10 minutes! Figured out the choke cable is broken, so dad was moving it under the hood. Once it would repeatedly crank/run, I decided to drive it around the property to have a little shakedown run. Went to shift into first & the clutch is stuck! Shut it off, cranked it in first & drove around the place 2-3 times with the clutch pedal in & bumping the throttle to try and break the clutch free. Finally called it quits so I could get cleaned up and make my birthday supper. When I pulled up next to the F250 and shut it down a puddle of coolant started pouring out. Couldn't see exactly where its coming from, but our bet is the radiator cap can't hold pressure any more.

Now I've got to try and convince grandpa to let me move the C30 into his hangar now that he sold his Cessna. That way I'd be able to get it out of the weather which would really help this weekend based on the forecast.

I also worked on/figured out some other stuff:
2.5" wide leaf springs, 40" on center
PTO hydraulic pump is not stuck, so that cable might be broken too?
Maximum size of under mount tool boxes is 40"Lx20"Tx20"D
Gear ratio is 4.56:1 (getting MPGs into the double digits just got harder!)
Axle shafts are 17 spline (@Croatan_Kid...we may need to talk if I don't swap rear ends)
My F250 OEM battery will not fit the C30 (I use CAT 9X9730 batteries in my F250), so I may end up moving the battery or modifying the tray

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Yup, that is the good ole' HO72 rear!
I am pretty sure there was a NP540 transmission that should bolt up to a sbc bellhousing. They have overdrive and non-overdrive versions. They are not readily available, but neither are 4.10 eaton gear sets. I think the OD version would give you the best of both worlds, 6.05 first gear and a 0.82 OD. Between an OD and FI, you should be into 12v cummins MPG in no time!
 
Cool truck!!

Have you considered the AA ranger:

760001M-27 : Chevy Ranger Torque Splitter Overdrive 27% with a 4.686 retainer index | Advance Adapters

This is what I am putting into my 53 GMC with a PTO.

Check my math please but 27% od should be: 4.56x.73 =3.33

I looked at the gear vendors over/under drive & $3k blows my budget! $1,700 is way better, but I'm hoping to have the truck on the road & reliable for under $4k...we'll see.


Yup, that is the good ole' HO72 rear!
I am pretty sure there was a NP540 transmission that should bolt up to a sbc bellhousing. They have overdrive and non-overdrive versions. They are not readily available, but neither are 4.10 eaton gear sets. I think the OD version would give you the best of both worlds, 6.05 first gear and a 0.82 OD. Between an OD and FI, you should be into 12v cummins MPG in no time!

Before I get into any of that, I've got the learn more about PTOs. Grandpa told me you have to know if its a heel or toe PTO and I've honestly got no clue! Hopefully I can move it out of the sun/rain this coming weekend (possibly wash it?) & maybe pull it around behind the tractor to free up the clutch. Crawled under it & didn't see an inspection cover to try and free it, so its either bump it loose or pull the transmission to break it free.

Chevy GM 5 speed transmission

Heavy Duty Truck Tranmission

I don't think either one of these are OD units, but it will give you an idea of what you are looking for.....eat your wheaties.....these look like they are going to be heavier than that NP205 last week!

For something that dirty/big/heavy I'd break out the F250...work doesn't mind me running personal errands if I'm in the area, but I don't think they'd sign off on putting one of those in the cab!
 
Worked on it this morning before the rain storms...dad thought he could pull it behind the tractor by the front of the frame/shoehorn where it attaches to the bumper. I suggested pulling from the rear hitch since I thought the front bumper would get damaged (not like its in pristine condition anyway). 2 bumps & the bolt pulled through the bumper...guess I'll call it character now? Reverse turns the engine too slow to be effective so that was vetoed pretty quickly too. So I did what I thought was best originally and pulled it onto ramps, found/removed the inspection cover & slid a putty knife between the clutch & flywheel while the clutch was disengaged...freed it up like a champ! Proceeded to drive around the place, shifting into each gear before I came to a decent turn & realized I have zero brakes! Downshifted and drug the tires enough to slow me down & made my way back to the ramps to work on the brakes & PTO. Master cylinder was bone dry so I topped it off with what I had on hand, but got the hydraulic pump to engage & raised/lowered the bed a few times. Brakes will be worked on tomorrow along with a new choke cable (if I find one), cleaning/lubing the PTO cable & diagnosing the temp sensor.

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Edit: stayed up too late Saturday night/Sunday morning trying to figure out what to do about the rear brakes and I still haven't figured it out what I'm going to do. Got the PTO cable much easier to operate by taking it apart, wiping/brushing down the cable, spraying silicone in the jacket & reassembling. Front caliper bleed screws were seized up so I sprayed them with PB for next time and topped off the master cylinder. Also got a spot cleared in the hangar for the C30 so its not sitting outside anymore.
 
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Well, I've got brakes now...good enough that I can stop quickly on hills & drive around grandpa's place without any concerns, but the fronts will need to be bled again/rebuilt & the rears rebuilt/swapped with 14b hubs before I put it on the road. Zero/sketchy brakes are a big fear/concern for me, especially when it'll be on the road with modern cars and 4 wheel discs.

I also picked up a '67 C10 fuel tank at myrtle beach last week so I cleaned it up, primed it & painted the top portion in case anyone glimpses it and to test how close the colors are. Planning on sealing the inside before bolting it in place & hooking up the fuel line.
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I also knocked down lots of major rust spots in the inner doors, rocker panels, floor and under the hood. Wiped down with acetone, primed & painted them...blue is a lot better color than rust! Planning on painting the floors with truck bed liner/undercoating, this was just to keep the rust from getting worse.
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Also removed the bench seat, cleaned it up & put the universal seat cover on. I bought this one since they said it has pockets down the entire front (5-6"?) for phones/tools/snacks. In reality they're only 2-3" deep...bummer. Its missing some hardware that ties the two slide rails together. Wasn't planning on fixing that since I'm 6'6" I'd leave it all the way back, but if I ever need to remove the seat or access the fuel tank, sliding it forward would be much easier...one more thing added to the list I guess!
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Not sure how I didn't remember this, but my dad & brother reminded me that grandpa originally built it to be a flat bed and then later converted it to PTO/dump bed to put gravel down on his driveway. When he converted it, he dropped the passenger side exhaust (true dual exhaust) to make room for the PTO shaft. I ended up ripping the passenger muffler off when I loaded it on my trailer Sunday afternoon; I knew that it was low, but not that low! Didn't get it home until 11:15 and decided it wasn't worth waking my neighbors with a straight-piped V8, so I waited until 6:30 this morning and added tucking the PTO shaft/exhaust to the list. Good news is I can start working on it during the week since its at my house & I have most of my tools already moved...just have to find/organize them!

We've been guessing at how much it weighs, with my guess at 6-6.5k, my brother at 7.5-8k, my dad at 6.5k. Once I got it loaded, I ran across the local feed mill scales to make sure I wasn't over my 17k tag & came in at 17.2k which with all the stuff I had in the F250 plus the stuff I keep on the trailer should put the C30 between 6.5-7k pounds. I'll weigh it again by itself when I get it closer to getting tagged and I'm going to look into weighted tag laws, but it needs to go on a diet!
 
Hi Brandon!,
6500 is what it's going to weigh, You ain't going to make much of a difference unless you remove something important like the bed.
And 6.5 MPG is what it will get with a gas motor. My '95 3500 with dump got 6.5 and my 2006 3500 gets 6.nothing. Find a 3:73 rear end and live with it.
Throw a HEI and TBI set up on it to get it sparking and burning and live with it.
Glad to see you're enjoying it!
 
Hi Brandon!,
6500 is what it's going to weigh, You ain't going to make much of a difference unless you remove something important like the bed.
And 6.5 MPG is what it will get with a gas motor. My '95 3500 with dump got 6.5 and my 2006 3500 gets 6.nothing. Find a 3:73 rear end and live with it.
Throw a HEI and TBI set up on it to get it sparking and burning and live with it.
Glad to see you're enjoying it!

Richard...long time!
Yeah, I've pretty much come to terms being "stuck" at 6.5-7k unless I cut the bed down. Alternative plan would be to win the lottery, go full send and get @MarsFab or @mcutler to build an aluminum dump bed...while that's a nice fantasy, it would absolutely nuke the budget! I'm keeping an eye out for a dually wheels/tires that don't use tubes and a 14B rear with 4.10 or 3.73 gears with a locker/limited-slip. I've also read that converting to rear discs doesn't help the braking too much and I'd essentially lose the parking brake, so I guess I'll stick with rear drums. Right now I'm working on getting the wrinkles ironed out (belts/hoses/plugs/wires/fluids, wire wheel/paint the floorpan, seal/install/plumb fuel tank, install wiring harness, exhaust work), which would be great to have them done before September 7th *cough* deer season *cough*. Then I'll start looking into upgrades (LEDs, 14B/13" drums, HEI/TBI, hydro clutch). I've got my dad's permission to add a lean-to or carport to the back of his shop for storage in Albemarle which puts it closer if anyone in the family wants/needs to use it (my brother has already asked to use it to haul gravel). I'll be damned I'm going to drive it 100+ miles and up to 70MPH just to chase bambi...my F250 got better MPGs towing it than I would get driving it!
 
Really cool project!

BTW, just realized you are right up the road from me. I'm in the New Light area.

Looks like you're only ~15 minutes down the road...I pass through Wake Forest everyday I go into the office. Glad that's only ~1.5 weeks a month since US1 brings the suck for traffic!

Been working outside all over Eastern NC the last couple of weeks (Southport, Smithfield, Selma, Wake Forest, Kinston & Lumberton) and the heat is killer so far this Summer! So the last thing I want to do is go outside & work on the C30 when I get home...hoping that will change with the cooler temps this weekend. I did prep/clean the fuel tank & sealed it with Red-Kote, but its still hanging in the garage before I put in the new sending unit & bolt it in.
 
Haven't been working on it like I should, but I've made a little bit of progress: tested the new sending unit & it works spot on, put on the new o-ring seal and assembled them on the tank. Next up was pulling the seat, priming/painting the floorpan & put the tank in place & then putting on the filler neck grommet...that thing was a real PAIN IN THE ASS!! Took me several tries to get that stupid grommet in place and finally got to put on the locking gas cap.

Another thing that slowed me down was the lock cylinder spring washer/retainer on my main toolbox fell off during transit from grandpa's to my garage. Took half a day to get the arm where I could grab it with a pair of needle nose pliers & get it to unlock. Also started reviewing the wiring harness instructions; hoping to get to that this weekend along with belts/hoses/plugs/wires/fluids. Also been looking for a battery box for a BCI Group 4D battery...thought about going with an OEM battery, but I get CAT 9X9730 for free & it'd be nice to have another battery that could jump the tractor, backhoe or F250 if needed. Probably going to end up putting it in an underbed toolbox if I can find 2 for cheap.

EDIT: forgot that I found some wiper blades & floor mats while unpacking that were meant for my old Accord...all have made their way to the C30.
 
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So I ordered several LEDs (tag, clearance, turn/rev/tail & side marker lights) & a back-up camera on amazon prime day...replaced the stock clearance lights & was laying out the side markers when it started getting dark. Decided to pull the C30 in front of the garage to get some light & I can't get it out of 1st gear & its not spinning over. Hoping the clutch is just stuck and its as easy to free as it was last time & that my jumper cables weren't making a good connection.
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Turns out the transmission just got stuck in 1st & the battery couldn't turn it over through the compression/gear reduction. Had to jump it with my F250 with some pressure on the shifter and as soon as it fired it immediately popped into neutral. Testing the battery it was 12.2VDC while sitting & 13.1VDC while running so I think the alternator is on the way out.

Pulled it over in front of the garage to pull sizes/part numbers off the belts/hoses & get some light on it. Swapped in the new H4 headlights & jacked the bumper up to try and get it back in place. Then decided to give it a wipe down since that's critical to getting it road worthy. Pics don't do the new lights any justice...
Halogen headlight:
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H4 headlight:
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Yes, I wear camo crocs!
"Cleaned" up:
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Didn't think the wiring would take this long, but I'm trying to get everything done/routed right instead of just slapping it together.

New belts/hoses/thermostat/temp sensor/choke cable/jamb swtiches arrived yesterday and I'll start working on them tonight...apparently I forgot to order a water pump, so it'll be added to the brakes order.
Upgraded the headlight wiring harness (uses relays directly off the power junction instead of routing to the switch in the cab)...plug & play FTW!
Troubleshot/repaired the birds nest of wiring for the LED clearance lights and added dielectric grease to everything.
Started ripping out the lights/hardware/wiring for the old bed marker lights...rusted hardware & wire nuts suck!
Decided to cut just over 6" from the vertical part of the bed & weld it to the rear for the tag & lights.
Got it registered/tagged for 13k & got the title sent off.

I've got about a quarter of the things on my to do list crossed off and I'm ~$1,500 in so far...should come in at ~$3,500 total.
 
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Didn't feel like working on it much over the weekend...regretting that decision now.

New belts installed & finally got the old bed lights off by using a pry bar to break the old hardware (can't find my power tools). All the new hardware is stainless so hopefully there's no issues with those unless they gall. Topped off the power steering pump with fluid & it pretty much ran out as fast as I filled it...another thing to add to the 'To Do List'.

Also, if anybody knows of 6 dually wheels & tires for a 1976-2000 Chevy/GMC that are for sale please let me know! 1976-2000 Chevy/GMC dually wheels & tires
 
Kinda put this on the back burner to make a big push on a project at work. Only have ~2 days of work in the field left & I'm waiting on parts so this is getting some more attention since deer season is less than 2 weeks away. One thing that's driving me up a wall is I cannot find my electric tool kit. Its in a neon yellow toolbag so it should be easy to find, but I'll be damned if I've seen it since the move! Also can't find my grinder to wire brush the rust off the bed/frame to get them painted. So I'll probably break down and buy new crimpers/strippers/soldering iron and find my toolbag as soon as I open/use them.
 
Ended up towing it back to Stanly County over labor day weekend & it seems that for everything I do on the C30 I have to add another 1-2 items to the list...guess I should have counted on that! Finishing up with my big project at work this week in Lumberton and I'm taking next Mon/Tues off to put in the new wiring harness.

Adjusted the carb & installed new choke cable (needs a return spring):
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Under hood light (can't find a tilt switch I like, gonna use a door jamb switch):
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Cut the headache rack down to use as a rear 'bumper' (plasma cutter started acting funny & then gave up the ghost, I'll have to trim/straighten it with a grinder):
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Tail/tag lights (tag light screws hit on a piece of angle, gonna raise them ~1/2"):
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Well it seems I just can't catch a break on this thing...got sick & was in bed last weekend and my two days off. Then this weekend I just couldn't bring myself to do much on it. Considering towing it back to the house to work on it during the week. Did find the reverse light switch on the transmission that my grandpa swore didn't exist and started tinkering with the speedometer cable to figure out why it doesn't work. It has some kind of adapter on the transmission that the speedometer cable threads onto...can't get either side to come loose. I did get some 3/8"-24 nuts turned down to weld to the door jambs that will accept the door jamb switches instead of tapping the sheet metal. New plugs/wires have been installed and the old ones will be thrown into the tool box for spares. Talked to the owner of Mid State Truck Beds about ordering two utility boxes that I'll do once the wiring is done. Since I missed having it ready by the opening day of deer season, the new goal is to drive it to supper on Thanksgiving.
 
New water pump, hoses, thermostat & gaskets tonight. Figured while I was at it I'd treat the pulley, spacer & fan to a fresh coat of paint...makes the old block look even older! Also put some JB weld on the fan shroud since it was cracked, got rid of some rust under the radiator and primed/painted the good metal to keep it that way.

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I'd like to get the brake lights fully wired tomorrow to drive it a whole 5 miles to the Badin VFD BBQ.

EDIT - only a few people showed up the cook the 1,200 pounds of pork shoulders, so I ended up helping the VFD until 2-3 am and then was back at it when I woke up to help set-up/serve/clean until 3-4pm. My back was feeling it after being on concrete that long so Saturday afternoon/evening was spent just laying on the floor. Then with the much needed rain on Sunday, I didn't feel like crawling under/around the C30 (parked on grass & not covered) but at least the cooling system has been gone through. Just gonna replace the temp sensor & that'll be one more thing checked off the list!
 
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