Geoff Weeks

Somewhere, I have the sales lit. When I 1st pulled it from the scrap yard, I dove deep into research on it. That was many years ago, and I can't lay my hands on the info sheets, but remember the general spec's The GM diesel was one option, as was a large Wauk and Herc, both on Butane. Transmission were 5 speed and 3 speed aux with power-tower. As I said, the winch and rear axles were gone, as was the aux and power-tower. I purchased a 4 speed aux for it. Best I can tell, mine was built around '53. Dart made "off road" trucks the "100" and "150 oilfield" (mine) were the smallest trucks they made (at that timeframe) and the only of "legal" dimensions. The GVW rating of the truck alone was either 60K or 66K (I don't remember all these years later), more than most road tractors today. The GM 6-71 was smaller than the big Wauk of the day There is no way to tell if mine was a "re-power" or spec'd with the 6-71, what is likely, is it is a replacement block. Only question is what the original block mfg was? The yard I pulled it out of was padlocked, left un changed, from around 1962, that much is known. I bought it from the son of the yard owner, when the town forced him to clean it up in the early 2000's There were lots of old trucks, but none newer then the 50's. H model Mack, a Diamond T (that today, I wished I had bought instead) most missing their rear axles. That means my Dart likely had a working life of less then 10years. That is why the body remained in such good condition, however the frame had been beat to hell. The front axle was moved back, the steering column and box relocated, so it entered the cab in a more vertical position, the clutch pedal/lever extended so the operator could turn around and run the winch from the drivers seat. Winch brake control is mounted on the back wall between the seats. The person that found this yard, and worked to find the trucks a new home, sent me a super-8 movie converted to disk of either my truck or its sister, working the Oklahoma oil patch in the 50's. The abuse the trucks suffered make a 10 years in the wildcatting oil field seam more like 50 years of more normal use. At one point mine (or its sister) were loading the draw-works, and the front axle was up off the ground at a 45 deg angle, and they didn't slow down the winch, next second, it came crashing down as the C/G past the rear axles! The Mack H model was beyond hope, but the Diamond T looked like it could be driven out if it had a rear axle. It was a lighter model, but I don't remember the number, Had a IHC medium six, (could have been a 269 or may be a 308) and the leather protectors on the hood corners will in good shape, the gauges (always a strong point on Diamond T's) looked perfect. I chose the Dart because of it's rarity and because I thought (and hoped) it would be easier to find a home for the Diamond T. There were 50's livestock and car carrier trailers, as well.

Bolt still show as being available. I don't know what size so just did a "generic" search. https://www.fleetpride.com/parts/euclid-brake-lining/01tUZ000001qhxpYAA Have to look for lining blocks. Both will likely be a "special order" but you could have pride in saying I re-line my own brakes when I restored my truck! https://www.maxitrucks.com/products/4709-brake-lining-set-23k never mind, that brake block set say Eaton ES, but I bet they have others.

That was and add on, it sits outside the hood/bonnet. Shop made. The triple air cleaner was a GM mfg part but where it sits isn't. Unfortunately it got hit when the truck was moved, and the cast aluminum cracked, but is repairable. It was set up to mount to the blower directly. The hood was modified from original, there is evidence of a vertical exhaust exiting through the hood on the right hand side. There is some evidence, like the air cleaner and exh that this was a re-power, although sales lit show the 6-71 as one of the engine options. The engine number is hand stamped in the block and one is "upside down", it has a rear mounted (gear driven) generator that the cab floor was "boxed in" around, that doesn't look like how the factory would have done it.

AFAIK there is no advantage to bolt on linings, Bolt or rivet, either is fine. Cast shoes, unless cracked, or abused are great for those that re-line. They are the heavy duty option, and with core charge, I'd hang on them. I have one set of cast shoes in my core pile, unfortunately they are 16.5 x 6", which is not very useful. Q brakes, are fine in the wider sizes with two webs, I prefer pin brakes on the narrower sizes used on the steer axle.

I haven't seen bolt-on linings in 30+ years!

If your going to do it, and just one wheel, send your shoes off and have them re-lined, and have them order a hardware kit when the shoes go in. That way it all goes back together easy.

4515 is a common "Rockwell" shoe, you have "pin style" and cast, both of which makes it different than a 4515Q. I would not let those cast shoes go without being paid for. I know some people run them through a "hot tank" to clean, but with mixed results. Hobby truck, clean as best you can and let it go at that, or replace and be done.

Not sure this is what you have or not, but is shows not only the shoes are available but the worth of the "Core" ! Don't let the cores disappear without a receipt for them! https://www.anythingtruck.com/product/510-SS4515CAST.html Abex Premium Relined Brake Shoe 23K GAWR FT4515CASTNS | FleetPride Check-out F-P core charge!

Other may have better advice, Mack's are not my strong suite. Take the brake shoes and spring to your local parts house. get relined shoes and hardware kit. One broken spring will likely mean others are not far behind. Shoes that have soaked in oil for a long time likely can't be cleaned. Being it is that old, you may have to have your shoes relined, but IIRC they are cast, so should be no problem. Look at the other wheels, if you have to get re-lined shoes, might as well get them all done at once, rather than piece-meal. So far I've only been stumped once on a spring. I have been able to get all the spec's but no springs.

@67RModel asked for some picture, these are lousy but the best I can manage. Only rust out is near the hinge on the LF door. Rear cab window slide down so you can work winch controls behind the cab. Window glass except windshield is all wrap in metal frame. I got new windshield and side glass soon after I pulled it to protect for the short time it was outside. Lots of hacking and welding on the frame, make it a good candidate for a frame swap.

I've had several computer H/D problem so have lost a lot of pictures I had. It is now stuff in the back a my barn, likely to be passed on to someone else who can give it the love it needs. It was worked hard and then sat in a closed junk yard from the early 60's until I saved it from going to China in the early 2000's. Rears and massive winch were gone by the time I got it. Body is in great shape for its age, and likely the best thing is for a body swap to a new chassie. I'll try and get more pic's but they will not be great due to the location and stuff around it. Attached is a WAI from JOT. Mine has shop made "pit" fenders. That one has the fenders it would have come with from the factory. This picture might even be mine from its early days, IDK. edit: It is not mine, that has vents on the hood side panel, mine has louvers.

The interesting thing in the 50's is, while the 6-71 2 valve at that time was rated at 200 hp (later improved breathing brought it up to 238) right smack in the hp range of all competitors, both gas and diesel, it doesn't seam to be found in many trucks of the time. Cummins had the 220, many gas engines in the 175-200 range. It lends credence to the story that GM wouldn't sell. P.I.E. experimented with a 6-110, which was a disaster, with the "pin wheel" blower, might have done well with the later Roots. The Buda 844 was the outlier and high HP engine of the day, but had trouble staying together and on the road.

From the cab sheet metal( or sub frame) to the engine block and from the cab sheet metal( or sub frame) to the truck frame.

I have heard, and saw written in an ATHS that GM was very reluctant to sell the (at that time, called) GM diesel to any competitor that was producing truck that GMC line was in competition with. I know they did, My Dart has one and it is listed in the sales lit as one of the engine options. It was a low production truck that GM didn't have anything in the line up that competed with it. Dart was a heavy, mostly off road/oilfield truck. I don't doubt what you say at all, just wondering about the logic at GM? How did they look at Mack vs other Mfg? When it was re-badged Detroit sometime in the 60's that thinking at GM changed, I think they found they could sell more engines than heavy trucks! IHC, and Ford used a lot of 6-71's as well as V8's, KW- Pete installed a fair number of the V8's. I know plenty were put in trucks as a re-power by end users, but in the 50's it was few and far between, that it was a factory install. Most of the mfg were still making and installing gasoline engines. At that time, all large trucks used vendor supplied diesel except Mack, who had their own, just makes me wonder? I would think the "story" I got told was "backwards" , that the other MFG were reluctant to install a GM engine, but that doesn't explain KW-Pete and others that used vendor engines exclusively? 50's were an interesting time in truck mfg.

Depends on which way you circle the globe!

On Eaton/Fuller you can swap in either input, but everyone uses 2" now. All I ran except my Marmon was 14" organic 2" shaft. Haven't had the trans or clutch out on the Marmon, but would bet it is 15.5 puck.

Ah, you too? National was my last choice, IDK why I had trouble with them? CR Classic with the correct driver made quick work, but the old seal, a flat plate and some careful hammer work would get the new seal in without damage if needs must. Since all my trucks and trailers only used a few seal numbers, I kept some on hand. I had spokes, so a brake job meant a seal change as well. One trailer had inboard stud pilot, so that was another that needed a seal change for a brake job.

Always a risk, someone doing something different. The "theory" behind the blunt or rounded end chisel is that concentrates the blow in a small area, it thins and expands the ring, without cutting.

I shout out for CR Classic, not the easiest to install, best done with the correct installation tool. In the end, you will learn what works best for you. There is no "wrong" mfg, it is what has worked best in the past and what is readily available in your area.

That is good news for you. A good coupla hits with a blunt chisel and it should come off. Wear rings are a great idea, made for something that is going to need service, unitized seals goes a step further, and makes the seal and wear ring all in one piece. You should have good luck getting it all sealed back up, regardless if you use grease or oil.

Take one of your old tube type rims and make a fire pit. Put the hub in the pit and wash all the oil out with diesel or kero, then wash with Dawn somewhere else, put some wood in the pit and have a fire to get rid of all the evidence!

Glad to get confirmation that my short term memory isn't totally shot! I thought I read that on here.

Outer seal was used with greased bearing in most cases. I think there is one where one bearing is in oil and the other in grease, that was mentioned a while ago on this site. I never saw that in my time.

Likely an old Stemco, and we are seeing the "wedding band". That is good news, as you can remove the band and replace with a modern unitized seal.

Look around the spindle where the seal rides, does it look to be one piece or is there a ring pressed on? What seal did it have? Stemco (leather) or something else? If it was a Stemco, you can remove the "wedding band" and use a unitized seal in its place. Something that old, I wouldn't want to say for sure. I know the English buses had a replaceable thick ring the seal rode on. I know the old felt seals (grease, not for oil) rode on the axle housing directly. If it does have a ring, to remove it, take a blunt chisel and hit the band in two places 90 deg from each other, you want to deform and expand the band, not cut it, and risk damage to the spindle that can leak.