Custom Driveshaft

[hostile]

The engine rocks front to back, unlike the trucks your talking about. The transfer case is changing angle on the entire drive shaft when the engine rocks under power.

It is much easier making a drivshaft work in a normal inline configuration.

CV joints in lifted trucks are always a big problem, they go out all the time when angles are bad.

 

[wishihadatalon]

Maybe I am missing something here, but what is the problem with making it a 1 piece shaft?

the T-case is a slip yoke.. this is enough adjustment to not need and other carriers.

the rear end is solid mounted so pinion angle is preset and will not move more then a degree or 2 under extreme conditions (unless something is loose).

the problem I see with the stock 3 piece is this. take a ratchet with a extension then put 2 swivel attachments on it then try to use it. it will try to collapse on itself. so in the case of our D-shaft if there is any pinion angle at all the driveshaft will attempt to bend and wobble in the carrier (wearing it out)

and pinion in a 1 piece is no big deal look and just about ANY RWD vehicle with a solid rear end they are open to ALOT of suspension travel and all that travel equates to pinion change which means the u-joints are no longer straight.


I am doing this mod because I know I have atleast 1 u-joint bad both carriers are already filled but the mount bushings are screwed. and thats just alot of unstable rotational mass to deal with.

I have made 2 driveshafts in the past for trucks with no problems so i will try this.

From my understanding you atleast need a 2 piece. With the engine always changing and the anlge not exactly right you would have to have a solid car with a motor that doesn't pitch otherwise it will just bind up.

 

[GRNDSM]

Maybe I am missing something here, but what is the problem with making it a 1 piece shaft?

You are missing something . Unlike typical RWD configuration, our transfer case ends much closer to the front of the car. This means that DSM driveshaft much be MUCH longer.

That extra length, combined with relatively high driveshaft speed (high rear end gear ratio and small tire diameter) makes for really nasty vibration problems. Plus, we might have some alignment issues. Both yokes must be on parallel axles, and our layout might be a bit different. This pretty much rules out the use of a single piece metal driveshaft. I have heard of people trying using aluminum shafts, which experienced dangerous vibration over 100mph.

But carbon fiber, which (when properly designed) can have some excellent damping quality! So if you are willing to pay $1500-$2000, you can have your very own CF driveshaft.

A much cheaper compromise (~$600) is to combine two (out of 3) factory driveshafts into one aluminum shaft and then still use one factory member.

 

[myblack98gst]

Do you not know the overal purpose of a U-joint? It is there to allow angle in the driveshaft.

You are correct the transmission of a inline motor conifiguration does not move but the rear axle does move quite alot. Before DSM's I was heavy into air suspension and my truck had 15" of suspension travel in the rear and it would drive fine at every angle.

The transfer case MIGHT have 2" of movement but that would be if you had really bad motor mounts. In anycase the U-joint would more than be able to compensate for this change.

Even if it is a 2 piece design there is still going to be an angle at the transfer case and the first joint. infact it would be more angle than if it were a 1 piece because the shorter the section of shaft the more of an angle it puts

 

[myblack98gst]

You are missing something . Unlike typical RWD configuration, our transfer case ends much closer to the front of the car. This means that DSM driveshaft much be MUCH longer.

That extra length, combined with relatively high driveshaft speed (high rear end gear ratio and small tire diameter) makes for really nasty vibration problems. Plus, we might have some alignment issues. Both yokes must be on parallel axles, and our layout might be a bit different. This pretty much rules out the use of a single piece metal driveshaft. I have heard of people trying using aluminum shafts, which experienced dangerous vibration over 100mph.

But carbon fiber, which (when properly designed) can have some excellent damping quality! So if you are willing to pay $1500-$2000, you can have your very own CF driveshaft.

A much cheaper compromise (~$600) is to combine two (out of 3) factory driveshafts into one aluminum shaft and then still use one factory member.

this is something I did not think about but I supose it makes sense..

 

[GRNDSM]

This should give you an idea just how long one piece driveshaft is:

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[wishihadatalon]

This should give you an idea just how long one piece driveshaft is:

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That is very long. So I was wondering what the benefits to a c/f shaft would be. Like if you ran a aluminum one for 2 of the 3 stock section and the c/f for the other section. Would that take a lot of the stress from the drivetrain?