My engine suffered a broken crankshaft and broken piston. Not bad after nearly 70 years. I knew that a rebuild would be needed at some point and wondered how much this would cost. Now that I am doing an engine/transmission rebuild, I (will) have the answer.
All parts came from the very helpful staff at http://www.vintagepowerwagons.com/ who have been willing to take some time to guide me with parts choices based on their experience. Information like what things wear and should be periodically replaced was very helpful.
Parts breakdown (prices are rounded, some minor items omitted, ask VPW for recommendations):
| Part | Notes | Cost |
| Crankshaft | Only required if broken or out of spec, difficult to get, shipping very expensive | $550 |
| Manifold assembly | Mine was cracked, I got a coated replacement | $500 |
| Fuel line set | Complete set with armor springs | $400 |
| Carburetor | $300 | |
| Oil pump | $300 | |
| Valve tappets (12) | $300 | |
| Flywheel assembly | $75 | |
| Fuel pump | $200 | |
| Motor Mounts | Rubber was aging on mine | $100 |
| Spark plug set and wires | $75 | |
| Crankshaft pulley | Mine had a dent | $60 |
| Timing chain | $90 | |
| Oil hose set | I opted to replace all rubber parts | $40 |
| Water pump | Mine was ok but replaced anyway | $100 |
| Ignition coil | $50 | |
| Piston ring set | $100 | |
| Pistons (6) | One of mine split | $200 |
| Camshaft | Fuel pump track was gouged on mine | $150 |
| Piston pin bushing set | $50 | |
| Timing gears, camshaft | $70 | |
| Timing gears, crankshaft | $50 | |
| Valve seats and intake valves (6) | $150 | |
| Distributor rebuild | Vintage Power Wagons performs this service | $350 |
| Valve seats and exhaust valves (6) | Machine shop found these | |
| Camshaft bearings | $50 | |
| Valve guides (12) | $60 | |
| Clutch kit | https://dcmclassics.com/clutch-components/496-cc-306-complete-package-clutch-disc-pressure-plate-throw-out.html – 10″ From DCM Classics Would have been on backorder for awhile with other vendors | $350 |
| Engine gasket set | Machine shop found these | |
| Rear main seal (neoprene) | Machine shop found these | |
| Crankshaft bearing set | Machine shop found these | |
| Connecting rod bearing set | Machine shop found these | |
| U-Joint set | $230 | |
| Flange bolts for U-joints | $75 | |
| Tie rod ends (2) and repair kits | $120 | |
| Drag link repair kit | $140 | |
| Idler arm shaft and bushing | $35 | |
| Drag link dust covers (3) | $75 | |
| Steering arm | Original ball joint was worn, you can’t replace the ball on the original, VPW had a rebuilt original for a good price. I had an idler arm that came with the truck | $50 |
| Brake Line Set (steel w spring protector) | Vintage Power Wagons sells a complete set of brake lines. Getting under the vehicle showed some corrosion on the lines and the brake light switch section was falling apart so decided to just replace everything | $250 |
| Brake light switch set (Packard) | Packard connectors seem to be more stable than the original shell types | $50 |
| Radiator Recore | Done at B & D Radiator Shop in McLouth KS. Last army depot went bananas with solder so B&D cleaned that up and recored it since this old radiator was devolving pinholes. | $700 |
| Transmission rebuild | Done at Smith Brothers, Topeka http://www.smithbrotherstransmission.com/ – Took a bit to find a shop interested in this transmission, was happy to find a shop that seemed genuinely interested in getting this old truck back in motion | $2000 |
| Machine Shop | Done at NAPA North Topeka http://www.napaonline.com/en/ks/topeka/store/27344/ very helpful machinists there, have been very detailed | $5500 |
| Mechanic | Retired mechanic with good reputation and familiarity with Dodge Power Wagons | Pending, estimate 3-4k |
| Total | Pending, $12-16k? |
Parts are still available but getting difficult to find. None of this has been fast, or cheap. I was able to save money on shipping by picking up the parts, Vintage Power Wagons is only about 4 hours away. My initial guess as to what this might cost was very wrong, it is about double triple what I thought it might be. Once I have final numbers, I’ll provide rounded figures in case someone has the same question I had about scale of pricing for a Dodge M37 engine/transmission rebuild.