Duramax Aluminum Driveshaft installed

[ChrisKringle]

Just got it on, 2500 short bed. Had it laying around, paid $75 for it new at NPS industrial market ($750 from dealer). Cost another $75 to have it shortened and balanced.



Guess I could have sold it for much more, but thought it would be pretty cool on my truck. Plus it's 19 lbs. lighter (44lbs to 25lbs), and that's minus oem harmonic balancer on tranfer case yoke as well.



Made from Alcoa seemless 6061-T6. Shop said it didn't need to be heat treated after, although obviously welding will anneal the T6 heat treat in the heat affect zone. More than one shop told me all day every day be just fine...

 

[justinp20012500]

Must of missed that one.



I was there looking at the "in the counter top sink" for my bathroom.



Pretty cool place, but over the past 6 years it has become very popular and expensive. (compared to the old locations)



Good find!!



So is a Dmax drive line suppose to be stronger then a dodge one?



Has anyone ever made "fine art" out of a factory dodge drive line??





Justin

 

[RKerner]

you may want to do some ciphering...

Made from Alcoa seemless 6061-T6. Shop said it didn't need to be heat treated after, although obviously welding will anneal the T6 heat treat in the heat affect zone. More than one shop told me all day every day be just fine...

It depends what's carrying the load at the weld. Is there cross section of the yoke behind the weld or is it just the tube? If it's only the tube cross section, it is now at T0, which has a yield strength of 8ksi versus 18ksi for T6/T651. If you find the wall thickness and diameter of the tube, you can calculate the stress in torsion;



Torsional Stress = Torque * 12 * tube radius (inches)/ J (polar moment of inertia)



where J = pi * (outside diameter^4 - inside diameter^4)/32 all dimensions in inches.



Insert the values you measured, assume you have somewhere around an extra 400-500lb-ft of torque above the 500 and change of a stocker, find the stress and see if it is about 30-50% of the smallest value given above. If not, well, at least it's light. By the bombs you list, I would look at installing a driveshaft loop so you don't mess up your aeroturbine or fuel tank when you find that it may have been prudent to re-harden the driveshaft. YMMV

 

[ChrisKringle]

Driveshaft loops yes. Welded tube to yoke so... , maybe I could get it T6'ed again just in case? How much?



I think the yoke on the end is billet, so tube to billet.



I see the D-Max in ATS's video running what appears to be OEM aluminum, at 12. 86 looks like it's holding.

 

[p-Bar]

My 99' Dodgeram 2500 SB gasser had the largest dia. aluminum drive line I have seen on a PU. Check one out and keep the Chevy stuff off our Rams

 

[Yo Hoot]

It's a big shaft but it's really thin walled. Did you tap it and hear the thinness of it? It has to be . 06" or less wall thickness. I've seen one twisted. GM uses it to replace a two piece shaft that they had launch shudder problems with. It's so long they needed to design something light and cost effective.



I'm not saying you made a wrong decision. I'm sure it will hold up well. They all twist or break joints when way overloaded.

 

[Po' Riggity]

99% of all aluminum driveshafts are junk. I'll keep my stocker, and the added weight.

Scott

 

[ChrisKringle]

Why are aluminum driveshafts junk? Don't they use them in drag racing, along with carbon fiber?



OEM I just took out is 1020 cold rolled steel, isn't 6061-T6 a stronger metal?



Well I kept the stocker just in case, maybe I'll sell the alum. one on ebay. I'm gonna run it for a bit though.

 

[Tim]

Driveshaft should never fail unless it is binding. I would be shocked to see a tube that large twist. I wouldn't worry about the weld, either.



Your tires should spin long before you can destroy a driveshaft..... unless you can bind it up.



Did the u joint fit in the stock pinion yoke without any issues?

 

[ChrisKringle]

The local shop here (Six States, those guys are great) did the pressing of u-joints. They did not mention any issues. The movement of the joint in the caps which are pressed into the oem yoke is tighter than the movement of the caps to driveshaft. Those are the joints that came installed in the shaft. I do not know if that is an issue or not.

 

[RKerner]

never is like infinity?...

It's worth a little yellow page search to see if there is a local aluminum extrusion house in your neighborhood. All you would have to do is remove the u-joints and all they do is put it in an oven with some other 6061 and the weld integrity issue is moot. If you do it right, it shouldn't cost hardly anything.



Tim mentioned it should never break unless... Never is like infinity (it's length is indesrcibable) and someone always finds a new way to create a failure. With your stack, all you would have to do is launch in 2WD with sticky tires or race someone with 10K in tow to apply enough torque (with the boxes tuned up) to expose something that should 'never' happen.



But, you may also need to do some lurking on the dmax boards to research any issues they have had or what the bombers do with aluminium shafts. Good luck.



Or, if you find the novelty wearing off, I'll pick it up from you for what you have in it .

 

[Forrest Nearing]

My 99' Dodgeram 2500 SB gasser had the largest dia. aluminum drive line I have seen on a PU. Check one out and keep the Chevy stuff off our Rams

no offense, but statements like these are just plain ignorant. Chevy didn't make that driveshaft... Spicer did... you know, the same people that made the axles that were in your " 99' Dodgeram"?



You know Dodge doesn't make the Cummins either, right?

 

[Tim]

Tim mentioned it should never break unless... Never is like infinity (it's length is indesrcibable) and someone always finds a new way to create a failure. With your stack, all you would have to do is launch in 2WD with sticky tires or race someone with 10K in tow to apply enough torque (with the boxes tuned up) to expose something that should 'never' happen.

I disagree. Unless there is a total lack of maintenance, I don't think that you could possibly break that driveshaft under torque. With a severe shock load it may be possible, but I doubt it. Our trucks use very large u joints.

 

[ChrisKringle]

It's worth a little yellow page search to see if there is a local aluminum extrusion house in your neighborhood. All you would have to do is remove the u-joints and all they do is put it in an oven with some other 6061 and the weld integrity issue is moot. If you do it right, it shouldn't cost hardly anything.



Tim mentioned it should never break unless... Never is like infinity (it's length is indesrcibable) and someone always finds a new way to create a failure. With your stack, all you would have to do is launch in 2WD with sticky tires or race someone with 10K in tow to apply enough torque (with the boxes tuned up) to expose something that should 'never' happen.



But, you may also need to do some lurking on the dmax boards to research any issues they have had or what the bombers do with aluminium shafts. Good luck.



Or, if you find the novelty wearing off, I'll pick it up from you for what you have in it .

Yeah maybe I'll get it oven baked again. Only problem is they epoxied the balancing weight on. Guess they didn't have a gas tungsten arc welding torch laying around. Suppose I could scribe around the "quarter" sized weights, scrape the epoxy, and tack each side real quick.



Anyone see a D-Max candy cane one? I haven't heard of it.

 

[Po' Riggity]

Its not going to break under normal circumstances, but being that Ive twisted 2 steel drivelines in half in my jeep when rockcrawling, Im ALWAYS leary of aluminum. If your truck is being used for pulling competitions, it wouldnt surprise me if the occasional driveshaft twisted in half.

Scott

 

[Hammer]

I disagree. Unless there is a total lack of maintenance, I don't think that you could possibly break that driveshaft under torque. With a severe shock load it may be possible, but I doubt it. Our trucks use very large u joints.

I have seen MANY aluminum driveshafts twisted into pretzels both under shock load and under acceleration load. This is a well known trick for the NHRA Stock/Superstock class racers when they are in a "heads-up" race with another car from their class. The aluminum driveshafts can be worth as much as a tenth and a tenth in a "heads-up" race is alot to have in your pocket for when its needed. Now,how they will perform in our trucks has always been a question in my mind. I could see every day driving them lasting but with the instant low end torque our trucks are known to make I'd be willling to say the pretzel twist will be inevitable. Towing and sled pulling would be out of the question using them and not very safe in my mind. Instead of aluminum why not have one made out of moly tubing it will still save weight and be alot stronger... ... . Andy

 

[ChrisKringle]

I just had this one laying around, if it twists I'll go chromoly. What about 7075 aluminum? I don't see much use of that anywhere, 'cept for wheel spacers.

 

[Tim]

Po' Riggity,



Don't you have Jesse's drivelines in your jeep? You mean to tell me you twisted the tube on a High Angle Driveline?



I can see this done on under-engineered, modified stuff... but there is no reason to break a driveshaft in a truck with stock sized tires that has 1 1/2 ton u joints and 4" diameter tubing.