Driveshaft options

[brods]

Decided I'll do anything to get away from the AAM crap and will be replacing both front and rear shafts. Next decision is aluminum or steel. Aluminum seems to be the rage for the rear shaft, but is it really any better or just more expensive? Would like to buy locally (SE Michigan), but the shop would have to be familiar with sourcing standard Dana/Spicer sized parts to replace the ******* sized AAM stuff. Any opinions or advice welcome.

 

[seafish]

I have been running the oem aluminum rear DS on my 2005 4x4 G56 for several years now after the center support bushing/bearing went out for a second time. Advantages of the oem one piece aluminum DS is that it eliminates the center support bearing/bushing entirely, helps eliminate vibration on start-up, weighs MUCH less then the steel two piece and looks REALLY good. There is a specific mopar # for the aluminum ds that will fit your truck. If you purchase from a dealership, there WILL be a warning that you CAN'T use it due to interference of the carrier bearing support member, but ALL that means to you is that you need to remove four bolts that hold the CS support in place and remove the ENTIRE assembly from your truck..YAY!!! Then the one pice is plug n play. Recently saw a link that showed an online Mopar dealer selling the one piece aluminum DS for about $475 plus shipping, which is about as low as you can find it for. I'll try to find the link and part # for you.

 

[seafish]

Found it, even kless $$ then I remember-- this DS is ONLY for 3rd gen QC trucks with the 48RE transmission like yours…G56 will be a DIFFERENT number.


http://www.moparamerica.com/oe-mopar/52123161ac

 

[AH64ID]

For me it was cheaper to get a 1 piece drive shaft in aluminum with 1550 u-joints than it was to replace all 3 u-joints and the carrier bearing on the OEM setup.

I thought the only funky AAM joints were on the front axle and the driveshafts were all standard???

 

[lpennock]

Found it, even kless $$ then I remember-- this DS is ONLY for 3rd gen QC trucks with the 48RE transmission like yours…G56 will be a DIFFERENT number.


http://www.moparamerica.com/oe-mopar/52123161ac

Can you pull the number for a QCLB 4x4 with G56? (truck in the Sig)

 

[brods]

Found it, even kless $$ then I remember-- this DS is ONLY for 3rd gen QC trucks with the 48RE transmission like yours…G56 will be a DIFFERENT number.


http://www.moparamerica.com/oe-mopar/52123161ac

Thank you. The truck is a QC short bed though. I'll do some searching on that site as see what comes up, though I will not buy another driveshaft with the ******* sized AAM joints. I've had no luck with them whether they were installed at the factory or if they are aftermarket replacements. Fool me once.....fool me twice....fool me a third time then I am an idiot (well I might still be an idiot but you get the idea).

 

[AH64ID]

Thank you. The truck is a QC short bed though. I'll do some searching on that site as see what comes up, though I will not buy another driveshaft with the ******* sized AAM joints. I've had no luck with them whether they were installed at the factory or if they are aftermarket replacements. Fool me once.....fool me twice....fool me a third time then I am an idiot (well I might still be an idiot but you get the idea).

Where do you have odd sized joints? My OEM driveshaft had standard joints.

 

[cerberusiam]

fool me a third time then I am an idiot (well I might still be an idiot but you get the idea).

How $$ to be an idiot a bit longer? :-laf

You will have to have a custom shaft built. Driveline Service sin San Antonio is you bets bet so you go to the 1480 spicer joints and a full 5" aluminum tube. It just costs a bit more than the factory one.

Where do you have odd sized joints? My OEM driveshaft had standard joints.

Standard for the manual is the AAM 1485 u-joint. With some work the spicer will fit but it is not exactly right. I think the 1550 is the contra to the 1485 AAM joint.

 

[brods]

Where do you have odd sized joints? My OEM driveshaft had standard joints.

https://www.turbodieselregister.com...tions-on-U-Joints?highlight=driveshaft+ujoint

I didn't re-read the thread but this is one of many threads when guys first started changing driveline ujoints. Iirc AAM lock up dimension was something like 1/16 less than a standard ujoint which caused much grief. I sometimes wonder if the AAM engineers choose all their stupid ******* sizes and designs just to screw the aftermarket, because I cannot see any justification to to making a ujoint the same as an existing product but with a slightly smaller lock up. It would not be cheaper than an existing design. It saves no space or weight. I can see no functional advantage what so ever. And my real world experience shows they are inferior. This truck has eaten more ujoints than all my other vehicles over 35 years combined, and that includes my rock crawler with 42" tires.

 

[AH64ID]

Hmm, I was under the impression that the joints on my OEM shaft were 1480??

Anyhow the 1550's on there now are HUGE in comparison.

 

[brods]

How $$ to be an idiot a bit longer? :-laf

You will have to have a custom shaft built. Driveline Service sin San Antonio is you bets bet so you go to the 1480 spicer joints and a full 5" aluminum tube. It just costs a bit more than the factory one.
....

I am definitely leaning that way. Not sure if the aluminum is worth it over steel for my needs.

 

[cerberusiam]

Hmm, I was under the impression that the joints on my OEM shaft were 1480??

Anyhow the 1550's on there now are HUGE in comparison.

The 1485 was the factory joint. How did you get 1550's in there? custom DS?

I am definitely leaning that way. Not sure if the aluminum is worth it over steel for my needs.

You might be surprised how much the aluminum 5" shaft makes for vides and harmonics, from that aspect it is worth it. The steel shafts are terrible for transferring the harmonics of the engine, the factory shafts are better but still cause issues. The 4" to 5" design induces harmonics. The flange on the rear diff is another possible issue, although Drive Line Services say they have goo luck just fixing the shaft size issues. Removing that flange and going to a ubolt style yoke with the 5" shaft makes a HUGE difference in harmonics for sure.

 

[brods]

Good info, thanks. How does the flange add to the harmonics? Does it flex or have too much runout? Is there something to check (like the run out on the pinion flange) before making the final decision between flange or ubolts?

 

[AH64ID]

The custom shaft I ordered came with them... But it does have a MOPAR sticker on it...

 

[cerberusiam]

The custom shaft I ordered came with them... But it does have a MOPAR sticker on it...

I wonder if it is a C&C shaft? Got a number off the shaft assembly itself? AAM shows a 1555 ujoint they supply so maybe it is an option in an MD truck ????

Good info, thanks. How does the flange add to the harmonics? Does it flex or have too much runout? Is there something to check (like the run out on the pinion flange) before making the final decision between flange or ubolts?

If the flange was comparable to the front drive line at the t-case it would probably not be an issue. The rear flange drive does not have much of a lip to center it, one of the vibe troubleshooting action items is turn the flange 180 degrees and see if that helps. Doesn't embody a lot of confidence in QC or efficacy.

The ubolt yoke is a modified strap type the GM trucks use, they drill it out to use ubolts which are much better than straps even for holding. To do a 5" tube you have to have the custom slip joint DS provides as no one makes one for the 1480 ujoints, they are all 1410. It is almost $1000 by the time one gets the drive shaft and custom yoke. A custom one with stock joints, slip yoke, and flange drive is around $800.

 

[AH64ID]

I can go look and see if the sticker is still there.

IIRC 1550's are now on 3500's with the Aisin.

#ad

 

[cerberusiam]

Ahhhh, that would make sense with HO power levels.

 

[brods]

One last question before buying the rear shaft. The factory shafts worked great until the ujoint bearings rusted (within 50K miles each). Neither shaft worked the same after the joints were replaced (even when a driveshaft shop installed the joints and balanced the second shaft). So, any issues a few years from now when the u-joints in the aluminum shaft need replacing? Iirc, back when everyone was struggling with the ******* lockup dimension on the AAM joints, it came up that the u-joints for the GM aluminum shafts had a coating on them for some reason. Corrosion due to dissimilar metals causing problems? I want the next driveshaft to repairable, not be a throwaway item.

 

[cerberusiam]

If the DS uses the AAM joints the potential for problems is there. The ujoints fit too tight and it end sup bending the ears when replaced. Getting away from those joints back to a standard size joint and yoke is why the custom DS's are so popular.

 

[mfurrh55]

Yeah , i've put 3 sets in mine and i only have 146k on my truck, and you are right , they are tight, just make sure you grease them often, Monte