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Posted
1 hour ago, GTPprix said:

Contact us from the website if you'd like to discuss all of these are custom at this point but I know one of you said you reached out but we did not get anything just an FYI. 

I tried to contact thru your website. Twice but no response. How about a phone number to call?

Posted (edited)
8 minutes ago, Stephen L. Pannell said:

I tried to contact thru your website. Twice but no response. 

Found it in spam, one this morning and another one about 10 minutes ago you should see a reply now; sorry about that! 

Edited by GTPprix
Posted

I'm in for the pics of exploded driveshafts at 120+ mph.

 

Please post them.

  • Like 2
Posted
1 hour ago, CamGTP said:

I'm in for the pics of exploded driveshafts at 120+ mph.

 

Please post them.

Me too, iam in on that one and what's left of the truck.     :idiot:

Posted
18 hours ago, CamGTP said:

I'm in for the pics of exploded driveshafts at 120+ mph.

 

Please post them.

Probably won't see any from the new body style trucks with the big 4" diameter DS. Especially those with the high capacity towing package. 

Posted
On 7/15/2020 at 7:02 PM, GTPprix said:

Yup! Just like we do for the K2's and it we've done it on the T1's as well :)

I'm in if I get a T1...

Posted
5 hours ago, Stephen L. Pannell said:

Probably won't see any from the new body style trucks with the big 4" diameter DS. Especially those with the high capacity towing package. 

The drive shafts have been pretty much the same since mid 2000's for the aluminum style. They are that 3.5 to 4in size. The single cab long beds with aluminum shafts in some of those years got massive 5in shafts but that's not really the point here. The metal is paper thin, ever seen a shredded shaft??

 

If drive shafts from the K2XX body style can break, so with the T1XX trucks. They aren't going to make it better very much different when the exact same drivetrain parts are carried over from the previous trucks.

 

 

Posted (edited)

I am much more concerned with runout and weak U-joints and incorrect u-joint bearing cup seating which does lead to excessive shaft runout than I am about the shaft itself. IF you have qualms about your drive shaft, put it up on the rack and check runout front and rear with a quality dial indicator. Excessive runout will destroy stuff muy pronto and you will feel it long before it blows. A thin wall drive shaft can be very strong but a truck built for a towing capacity of 12,000 lbs isn't going to have a weak DS. If these drive shafts are that weak they would twist in two before you could even get a heavy 12000 lb trailer untracked.

Edited by Stephen L. Pannell
Posted

Most people I talk to that have had shafts break or the ones you see on youtube dyno runs don't feel the vibration until right before it goes boom. There's a thread on performance trucks.net with a guy doing 95mph and it just went with no warning.

 

I'm not saying they are weak in the fact that they can hold up to heavy towing and they do just fine even with 600hp. It's just the speed the shaft turns that grenades them. To me it's not worth the time to remove the stock shaft and have it taken to a shop so they can spin it up. Replace it with something better that will handle the speed without any question.

  • Like 1
Posted (edited)

The underlying and root problems of driveshaft failure has been addressed several times in tech bulletins and other research. Aluminium centrifuges spin at a rate of 12,000 to 90,000 rpm or up to 1500 rps and don't blow up. Drive shafts spin at a fraction of that. Research has shown that most failure aside from external damage like high centering on a boulder or something, are caused by several other factors. 

1. U joint sync

2. runout caused by worn or defective drive spline which is the main cause of u joint sync problems.

3. shaft out of balance.

4. incorrect drive line angle. can we say lifted trucks

5.  improper seating of the u joint bearing caps in the yoke cradle

If any of these items are out of parameter then high rpm harmonics can and will destroy the shaft.

Plenty of data on how to check these items and repair or correct. One of the main culprits has been output and input spline misalignment, wear and just poor quality in manufacture from 3rd party outsourcing of parts. There are GM tech bulletins on it as well.

I'm not saying that GM isn't at fault because they are. Cheap labor in Mexico perhaps during assembly. 

There is also an android app called NVH that can be purchased that will identify and pinpoint vibration locations and root causes.

NVH is expensive at $400. Don't think for a minute that NASCAR and NHRA top teams don't have tools to check and fix these errors.

These types of driveline vibrations gone to the extreme will destroy any long shaft regardless of what it's made of.

Also google youtube videos of how to check driveshaft balancing. There is a free phone app that will measure sync angles for the u joints.

Edited by Stephen L. Pannell
  • 2 months later...
Posted
On 7/15/2020 at 7:02 PM, GTPprix said:

Yup! Just like we do for the K2's and it we've done it on the T1's as well :)

Well I’m getting a T1.   So I would like to raise/eliminate the top speed governor please. 

Posted

My 19 crew cab 4x4 stops at 112... I just want to do 125.  My diff is 3.24.  Police Tahoes are 3.08 with shorter shafts... but there is nothing special about their DS versus a regular Tahoe.  I'll take my chances in the 120s, and will gladly post pictures of any carnage.   

Posted

Some have posted that the limiter set by factory based on the tires it was born with.

 

I can't verify,

but...police tahoe probably has different speed rating tires than crew cab 1/2 ton..

  • 2 weeks later...
Posted

White Auto and media advertises a speed limiter delete on the Modifications forum, but I also contacted Diablo Tune that said their tuner should be out in 3-4 weeks for my 2019 Silverado 6.2L

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