1980 Mack twin screw dump truck. Drive shaft turns going into front differential, but no go. Truck was trying to dump full load in soft ground. Bang when the driver let out the clutch. Canadian built Mack if it matters, top load differential. No axle weight on door. Just wondering if anyone has any words of wisdom or relevant experience to share.
Could be an axle shaft. Not terribly uncommon.
Pulling the axles would probably be a good start.
Top loaders were a different breed depending on the axle capacity as to how the MACK design Power Divider worked, We called the locking wedges Peanuts, if wedged tight enough at Wrong Time and Speed would shear a Thru Shaft.
I bet it is an axle. At Weyerhaeuser with the Macks from '73 into the '80s, we broke axles regularly. They were a weak link. All the trucks carried a set, you could change an axle in about 5 minutes if you had a shop modified axle. The truck shop had the machine shop score each axle about an inch from the spline. thus giving it a "weak point" to shear. It saved trying to retrieve chunks of axle from the differential. Keep the scored end out by the hub and it was really easy. The DM 8000s were notorious for eating axles.
Axle shafts you mean? Axle is the whole shabang, no? Ie Mack top loader axle.
Having internally splined Axle shaft end caps instead of flanges made broken axles on DMs somewhat easier, IIRC those had Mack 48k tandem ratings.
What is the easiest way to guess which axle? Jack tires and spin 1 at a time to see who spins most freely?
I've always just spun by hand and tried listening for clunks. But there's only 4 , so its not like there's infinite possibilities.
Yes, the shafts were the axles in our parlance.
Just remember that if one of those shaft/axles broke the chance there aren't some bits that won't come out when shaft is removed. I would hate to just slip a new shaft in and hope the other bits will not get some place they could do some more harm. I suppose one could inspect the two broken parts and determine what might be missing then flush the housings with fuel oil and play around with a magnet and hope everything comes out.
If you can lock the power divider and see what spins usually shorts out pretty quick what area is broke I usually have to pull both to knock the stubs out thank goodness we don't need as many as Jumbo did
Depending on where it broke if that's what it is--if it broke near drive unit a piece of pvc that fits the tube can be used as a receiver to remove broke stub.
The thing everyone loves--lockers--till it's driven on dry asphalt for a couple hundred. We had a series of Freightliner Classics with front lockers, drivers kept for getting to flip the air switch to disengage-then a sharp snap would be heard. After replacing about 6 axles-two in parking lots--those got disconnected. * Next everyone will say {didn't they hear the buzzer or see the light} they taped over the light and pumped the buzzer full of silicone. Drivers are some scheming buggers.
An axle is on a trailer. A rear housing, houses the axle, and the rear end, or dif. Tomato, potato
yes----glad you brought up the vegetable/garden association of pumpkins in a vehicle drive train. never did understand where that came from.
Third member, pot, pumpkin, drop in, carrier, is just a name and spoken differently around the nation. Axle tube, axle housing, Banjo housing, axle shaft, etc. we all here been around long enough to have heard 95% of the variables. Pop, Soda, Coke, soft drink!!
1980 would be old enough to have t 2 part axle, axle shaft, long splined on both ends thingy the makes wheels go. Would it not. Not sure when Mack went wit the one part
Flanged and or Double Splined have been around for a LONG time at Mack. Caped Dbl Spl were seemingly always on Heavier Axle arrangements, lighter got the Fanged sets, OLDER Trucks(Pre 70) many had Double Splined.
Yes I understand that----but pumpkin does not fit in that sentence. Two piece axles--I don't remember.
The ones I remembered had These for Axle Ends Newer Heavy Axles had these
The cap on the hub, and the axle were seperate? The cap on the 2 piece looked like a Chinese hat
Correct--I just don't remember the last year for those. The only good thing about those was --pull the cap remove the axle reinstall the cap for towing.
exactly
The 1992 I drove was a heavy spec truck, but had the one piece.
Last DM Series I saw with MASSIVE Third Members had the Eight Bolt heads, that was a 95/97 somewhere in there.
Axle ends look like DM 1st picture. It prolly wont be for a few months to get into it.
Few months!!
He likely doesn't need it to plant, probably needs it to harvest.
Nah, its pretty small/useless for farming. Was hauling broken concrete from tearing down old building, then hauling dirt to fill in the hole. Finished hauling the dirt with wheel loader. I put a 1/4" floor in the bed so don't have to be super careful with the concrete.
Broken axle shaft. Its easy for me to go catastrophizing about broken pinions or other expensive parts that would scrap the truck. 17 spline both ends, 39 11/16 long. No visible part number. I see several that fit that description on the net. Did Mack have few enough axles they are likely to fit? Or how to find a part number?
Should be a Rear Diff ID tag somewhere on it, if OE to truck Dealer should be able to ID by SN
Was it pumpkin or punk’n???
Punkin Trchno lingo!!!
Ford 9inch Pumkin better if it had the big N
Mama don't allow no stinking Pumpkins, Punk'n, Pumkin's around here, better mind what mama don't allow-cause mama don't allow no pumpkins around here.
Used to work for a company and one day a guy who was new dumped dumped clutch and same thing happened. Axle shaft twisted and snapped. Easy fix but the problem is you really have to take it all apart now and clean it. I knew a guy who changed his and didn't get all the pieces and chewed up the bearings. It's a pain but if you do it right you'll have piece of mind. I would at least pull the axles it's pretty quick to do it and see if they're snapped if not somthing else inside broke but 99% it's the axle
Ok, fixed now. Looks like at some time this axle shaft was in a wheel end where the bearings went out. Lots of scaring on the wheel end of the shaft and heat marks from rubbing. The shaft was a clean 90 degree break, not the elongated spiral usually associated with torsion failure. It didn't happen on this housing, as there was no scaring in the housing. If it hadn't broken this load, it would have happened shortly later. Not much left holding it together, and another break starting 1/8" away from this one. This was a 17 spline axle both ends. And Mack has both shallow spline and deep spline in 17 splines.
Good glad it was easy!
Where that "this thread is worthless without pics" emoji
Here ya go Note the wide flat between splines that shows shallow spline axle.
I don't know if one could be cut that straight, straightest break I've seen.
That's the cleanest break of one of those axles I have ever seen. I pictured a diagonal twisted fracture with all kinds of roughness and lots of metal chunks missing. That's why I was questioning chances of just slipping a new axle shaft in and putting back to work. I still might want to change the oil and check and clean magnetic plug(s) then after it has a few miles on it pull the magnetic plugs back out and see what there might be on them.
Ker-snap.... Nice acorn table btw.....
Just grind a bevel into that and weld it up!
That's what the pakistanis do
Would be worth it and make a video to post on line just to see how many "Likes" you get!
Yet those are the same people disassembling and ‘Polishing’ old taper roller bearing assemblies and welding broken crankshafts cams and blocks. Just saying a Little dubious of any life expectancy on any of those hours and hours of Fixes.
Looks like a break on a Weyerhaeuser truck with the scored axles. It obviously isn't because you cannot see the indent of the scoring. They used to score them about a 1/32ed deep and about 2" in from the spline. Scoring them and putting the scored end at the hub reduces searching for parts in the rearend. It also speeds up removal and replacement.