Dual double cardan joint 1350 front driveshaft and factory CV discussion.

[e_k_powell]

Have any of you that have put on the taller springs checked how off center the axle is? You are pushing the front up 2 1/2" with a non-adjustable front trackbar. Not only is there an increase vertical angle on the front driveshaft because of the longer springs, the front diff has shifted towards the driver side (US LHD) a bit. The axle has likely shifted 1/4" to 1/2" which isn't a lot but when you put both of these deviations on the CV joints in the driveshaft it increases chance of failure. Rear at only 1 1/2" lift probably isn't as much of a concern but I would think not only do you need a front driveshaft you probably also need an adjustable front track bar or at least a track bar bracket that will recenter the front axle.

 

[TD5-90]

The CV joint is bolted to transfer box and differential unit. If this is not called flange, what it is?

That's of course right, but that does not solve the problem: You can enlarge the distance between the diff or the xfer case and the CV joints to reduce the required length of the shaft, but at the penalty of further increasing the operating angle of the joints.
Take a piece of paper and draw it up. It's easy to see...

 

[ORSO]

when I had land 110 td5 I had both drive shafts made with double cardan joint by Italgiunti. The product was spectacular. In my opinion it could make an excellent product. I have doubts about the two flanges. It would be necessary to mount two that do not have the adaptation for the homokinetic.

https://www.italgiunticompany.com/

 

[Tom D]

So after I got off of work yesterday I figured I should give the CV boot an inspection on the front drive shaft after reading though this thread. This is what I found now after only driving about 200 miles since I installed the Eibach lift Part # E30-34-001-06-22 and 35"/12.5/R17 Toyo tires. Caster settings were adjusted down to 1.5degrees as recommended from the 2 nominal, but this still wasn't enough apparently to prevent CV boot failure. See pictures belowView attachment 7868371View attachment 7868372View attachment 7868373View attachment 7868374

Do these pictures show the shaft in position? i.e. still attached at both ends? The angle looks quite severe compared to stock.

 

[Shroomy]

Do these pictures show the shaft in position? i.e. still attached at both ends? The angle looks quite severe compared to stock.

Yes this Front Drive Shaft is still connected on both ends for now until a new drive shaft solution is made. I will not not be driving this Rig until I have a new DS to replace it with.

 

[PNW_IG]

I contacted Eibach tech support and told them I plan on doing a lift but was concerned about the front driveshaft failing. They responded this morning. They said they have sold hundreds of kits and done numerous installs and have seen no failures. They also said full extension is controlled by the shock not the spring. They also mentioned non lifted vehicles having failures. I would love to know if any of the non lifted failures are boot related or if they are experiencing the issue Logsplitter is dealing with.

 

[Tom D]

I contacted Eibach tech support and told them I plan on doing a lift but was concerned about the front driveshaft failing. They responded this morning. They said they have sold hundreds of kits and done numerous installs and have seen no failures. They also said full extension is controlled by the shock not the spring. They also mentioned non lifted vehicles having failures. I would love to know if any of the non lifted failures are boot related or if they are experiencing the issue Logsplitter is dealing with.

I'd like to know that too.

 

[bamanuke]

I contacted Eibach tech support and told them I plan on doing a lift but was concerned about the front driveshaft failing. They responded this morning. They said they have sold hundreds of kits and done numerous installs and have seen no failures. They also said full extension is controlled by the shock not the spring. They also mentioned non lifted vehicles having failures. I would love to know if any of the non lifted failures are boot related or if they are experiencing the issue Logsplitter is dealing with.

Date submitted: 08/25/2024
Reference number: 3149971972
Issue: New ticket created from form submission
Issue description: installed your 2.5" lift for my Grenadier. front driveshaft cv has failed at the transfer case end. Looks like this is a universal issue with these lift springs.~7500 miles with the lift springs installed. vehicle has been shipped to the dealership for inspection. just giving you a heads up. would love a response.

 

[Tinerfeño]

Take a piece of paper and draw it up. It's easy to see...

No need to draw, this was proposed as a solution if problem was inadequate reserve for elongation. Not for angle. Please read original text again.
As I can see the reason for failures is still unclear.

 

[Powers]

View: https://youtu.be/68OnPC5TgsI?si=rJ8IGB-3z_ykXnOy

View: https://youtu.be/8HP387BhRk8?si=-4N1D5syNy-RAG39

Seems to be a must do modification at this point....

 

[NQ94]

For the first question, presumably Magna did this, or at least validated Dana's work. If the count of failed shafts in unmodified vehicles has got IA's attention then I expect they will be taking another look.

For resonance, Bodhi Grenadier reported resonance at 65-70mph in part 2 of this video while road testing his prototype DDC driveshaft. 7th gear is ok. 8th gear has resonance. If this site is correct then 7th and 8th are both overdrives in the 8HP76 and 8HP50.

He suggests the standard driveshaft should be adequate for typical use at standard suspension height, albeit less than optimal due to the opposing angles of the transfer case and front diff nose.
[/QUOTE]

I would expect Magna and Ineos would of completed extensive testing and analysis in multiple scenarios to determine the suitable driveline design to comply with the other component manufacturers engineering demands.
I was more implying that we as owners and plenty of aftermarket companies have a tunnel vision approach to the end goal without considering other technical issues we cause when modifying vehicles.

 

[Zimm]

I contacted Eibach tech support and told them I plan on doing a lift but was concerned about the front driveshaft failing. They responded this morning. They said they have sold hundreds of kits and done numerous installs and have seen no failures. They also said full extension is controlled by the shock not the spring. They also mentioned non lifted vehicles having failures. I would love to know if any of the non lifted failures are boot related or if they are experiencing the issue Logsplitter is dealing with.

They aren't getting it. The issue isn't the CV and the angle, its the boot not being designed to be anything but strait in its neutral position.

 

[PNW_IG]

They aren't getting it. The issue isn't the CV and the angle, its the boot not being designed to be anything but strait in its neutral position.

They just responded to me again and wonder if the installer is dropping the axle too far pinching or otherwise damaging the boot. He said a spring compressor should be used to remove original springs as well as install new ones.

 

[Zimm]

They just responded to me again and wonder if the installer is dropping the axle too far pinching or otherwise damaging the boot. He said a spring compressor should be used to remove original springs as well as install new ones.

I can see that happening... I use a schable spring and strut compressor as it safer (highly recommend this style, those sticks will take an eye out) ... Now, the question is, does one have the room to position the compressor to get enough coils to avoid dropping the axle very far??? I don't know, I've avoided the lift until the rest of yinz beta test it.


Maybe just drop the shaft as part of the SOP.

 

[PNW_IG]

It seems like there have been more than a few installed. It could explain why failures are inconsistent.

 

[Tom D]

But... didn't some one say earlier that he had had one replaced post lift that had also failed?

 

[Johnp123]

But... didn't some one say earlier that he had had one replaced post lift that had also failed?

Me…

 

[Tazzieman]

I wonder if the famed Iceland modded monster truck Grenadier has had any issues?

 

[Clark Kent]

The automatic gearbox is ZF 8HP70, or am I wrong?

Sorry @Tinerfeño I missed this question.
Typo on my part. The B58 powered Grenadier uses the ZF 8HP51.
B57 Diesel uses the ZF 8HP76.
I haven't read any reference to 8HP70.

Edit: attached ZF model details from Ineos press pack.

Curious that the website I linked above states the maximum torque rating for the 8HP51 is 560Nm and the 8HP50 is 500Nm. Most sources I have seen list both models at 500Nm.

 

[Cheshire cat]

I was sent a picture by the company that had carried out the lift on the Grenadier belonging to George Ratcliffe himself. I guess that if he was to suffer any problems, it wouldn't be a big problem regardless.

The amount of fails involved, in my view could well be down to mistakes in fitting. I can see how a boot could easily be damaged. Or am I just wishful thinking?