Americas Front Driveshaft CV redesign

[Commodore]

Ineos crew, there is an issue with the front driveshaft CV at the transfer case side. The acute driveline angle generates heat causing the rubber on the CV to rip and spill grease. This leads to failure of the CV joint and ultimately immediate loss of forward propulsion. The failures have been well documented. Do you have plans to redesign this part or should owners start looking for their own permanent solutions?

This is a serious safety concern that needs to be resolved.

 

[Rayzar]

Apparently they are putting the able on a jig, grinding the welds off that hold the axle tubes into the diff housing, rotating it then welding it back up. DMW have dealers all around Australia. Apparently they will replace the whole front axle on an exchange basis.

Regards
Craig Murray

Watching this with interest. IF that front CV issue is resolved then i would seriously consider buying a Grenadier pending the cost to modify, and hope my purchase has a good working HVAC. Hoping ineos gets involved in this or doing something to address customers concerns as the Ineos aren't saying much lately.

 

[Clark Kent]

We're currently in Townsville visiting our son. JRace are 5 minutes away so I'll go visit them on Monday.

I dropped in today. Jay is the J in JRace. He was away but I got a good run down on their Grenadier development work from a team member. It's a comprehensive package that aims to address castor, the driveshaft, a modest suspension lift and a GVM* upgrade in a single kit. They are not doing an axle housing cut and turn.
I have emailed Jay to get his input and I will share more here after I get his response. Definately one to watch.

*Gross Vehicle Mass.
USA: GVWR
UK: GVW or MAM

JRace is an Australian Second Stage Manufacturer (SSM) which gives them federal certification and approval to do substantial modifications and re-engineering of vehicles while maintaining full compliance with the relevant design regs and roadworthiness requirements. That's an oversimplification. If you really want to know more go here.

https://www.infrastructure.gov.au/infrastructure-transport-vehicles/vehicles/road-vehicle-standards-laws/second-stage-manufacture

 

[ORSO]

keep us updated

 

[Zimm]

So what is anyone willing to pay for this service? It's a very easy process that I have done too many times to count. And Ineos gave us great bushings at the end of the tubes for alignment. Certainly some serious stuff to consider, but not Rocket Surgery by any means.

So what would people expect to pay for this. Let's say as an exchange axle. You send housing and a modified housing comes back to you with any other necessary components.

is the entire axle assembly to be blasted and repainted, or are we getting back in the white?

Stripped or are you doing the teardown and reassembly?

I'd actually say, instead of an exchange, offer to do a batch of 10 to people that don't care if the rig is down for 8-12 weeks.

 

[ORSO]

A question for the experts: would it be possible and useful to replace the transfer side CV joint and the relative flange to accommodate a larger CV joint?

 

[Dokatd]

is the entire axle assembly to be blasted and repainted, or are we getting back in the white?

Stripped or are you doing the teardown and reassembly?

I'd actually say, instead of an exchange, offer to do a batch of 10 to people that don't care if the rig is down for 8-12 weeks.

That's certainly where things can fluctuate. Tear down and rebuild of the axle is not a problem, but that's shop hours that have to be paid and somewhat profitable. Shipping an entire axle assembly is also a bit more costly than just shipping a bare housing.

Then if you start getting into blasting and say powder coating the housing you are looking at even more money.

That's why I was curious what everyone's expectations are. I can do the work, but I don't know that it's worth it to me these days. But if I was Agile or the like I would be much more focused if I knew what people think it's worth to make their beloved Gren drivable again. I know Agile has a housing on the shop floor currently and they are looking at options. But the Carraro axle does throw some curve balls. One or two that I personally feel are a god send and some that are potentially disastrous.

 

[Dokatd]

A question for the experts: would it be possible and useful to replace the transfer side CV joint and the relative flange to accommodate a larger CV joint?

Funny enough, I have actually found an ever so slightly smaller CV that would solve the problem as it has more range in the boot. But I'm not certain the reduction in size is worth the squeeze.

 

[Zimm]

Now, Dumb question, and I've never seen it done, but why can we not just replace the Tcase with a DC/centering ball unit and keep a CV at the diff. Is there some sort of instability at the DC side cause by the CV or excessive stress at the CV?

 

[Dokatd]

Now, Dumb question, and I've never seen it done, but why can we not just replace the Tcase with a DC/centering ball unit and keep a CV at the diff. Is there some sort of instability at the DC side cause by the CV or excessive stress at the CV?

No, and this has been proposed certainly by me quite awhile ago. That one guy over across the Atlantic has cobbled one together, I forget his name but maybe Sven? The problem is finding a shop that will and for that matter can balance that type of shaft. This is the direction I was trying to push Tom Woods and I even offered to front the money for tooling to balance. But since the angles were still out of spec they would not risk their reputation for such a small market.

I am still waiting on one more drive shaft company to give me the middle finger on this approach.

 

[Commodore]

No, and this has been proposed certainly by me quite awhile ago. That one guy over across the Atlantic has cobbled one together, I forget his name but maybe Sven? The problem is finding a shop that will and for that matter can balance that type of shaft. This is the direction I was trying to push Tom Woods and I even offered to front the money for tooling to balance. But since the angles were still out of spec they would not risk their reputation for such a small market.

I am still waiting on one more drive shaft company to give me the middle finger on this approach.

Yup, he did it with 1310 DC and the t-case side. That had to be almost a year ago and I haven’t heard a thing since. I was never in love with the 1310 size u-joints. They are definitely on the small size for this application.

 

[Dokatd]

Yup, he did it with 1310 DC and the t-case side. That had to be almost a year ago and I haven’t heard a thing since. I was never in love with the 1310 size u-joints. They are definitely on the small size for this application.

I very very much disagree with you on 1310's. 1350's are overused and overkill.

And Sven made a double double Cardan a year ago. And it vibrated too much just like everyone else's. Rather, about 2 months ago Sven posted a shaft made from a hacked up stock Grenadier shaft with a DC at the transfer case side and the stock Rzeppa at the diff side. This should handle relatively well but will still exceed the operating limits of a DC shaft. But agin it should behave much better than anything else we have seen. The issue is still creating this shaft professionally and balancing it.

 

[Zimm]

but will still exceed the operating limits of a DC shaft.

How is this operating outside the limits of the double cardon joint?

 

[Dokatd]

How is this operating outside the limits of the double cardon joint?

It exceeds the angle. DC joints have a much lower operating limit than Rzeppa joints. They just don't have a rubber boot to fail. DC joints will need the center section rebuilt every 30-50k miles give or take. Luckily the rebuild is cheap and moderately easy.

 

[Tom109]

DC = Double Cardon

What about a mutation with a CV mated to a single Cardon?

 

[Clark Kent]

I dropped in today. Jay is the J in JRace. He was away but I got a good run down on their Grenadier development work from a team member. It's a comprehensive package that aims to address castor, the driveshaft, a modest suspension lift and a GVM* upgrade in a single kit. They are not doing an axle housing cut and turn.
I have emailed Jay to get his input and I will share more here after I get his response. Definately one to watch.

*Gross Vehicle Mass.
USA: GVWR
UK: GVW or MAM

JRace is an Australian Second Stage Manufacturer (SSM) which gives them federal certification and approval to do substantial modifications and re-engineering of vehicles while maintaining full compliance with the relevant design regs and roadworthiness requirements. That's an oversimplification. If you really want to know more go here.

https://www.infrastructure.gov.au/infrastructure-transport-vehicles/vehicles/road-vehicle-standards-laws/second-stage-manufacture

I had a 30 minute call back from Jay yesterday afternoon (Thursday). Quite a lot to unpack from the call. Jay's background is in the light and heavy vehicle suspension and driveline alignment industry. He holds the relevant qualifications and knows his craft. He rattled off a lot of codes, design regs, specs, etc. that underpin the quality work that JRace does.

IA have been actively encouraging the Australian and USA aftermarket industry to do dev work on Grenadier and Quartermaster. Jay shared that Justin Hocevar (MD IA Australia) reached out to him some time back to develop a GVM upgrade because that's what Australian buyers wanted. Justin made a development vehicle available and linked Jay up with the IA Engineering team to develop the first GVM kit. Jay doesn't believe this was an exclusive arrangement, with other companies doing similar work around the same time. It does explain why we went from minimal aftermarket interest in Grenadier to several options becoming available in a short period. Kudos to Justin Hocevar.

Firstly, there is no golden goose solution forthcoming. Adjustable control arms to fix the lack of castor are done. Custom coils for a GVM upgrade and a 40mm lift (made by Eibach to JRace's own spec) are done. Custom length and valved Comp brand shocks are done (Jay has tested with Bilstein and Kings).
JRace already sell a 4000kg GVM upgrade kit for Grenadier. Standard AU spec GVM is 3550kg. He has tested GVM up to 4495kg but would not recommend this weight due to a design weakness in the rear axle housing (bracing would be required). Jay hopes to roll out a GVM upgrade + lift + driveshaft kit in the 2nd quarter of 2026 (April-June). Part of the delay is IA need to first re-do their type approval of the vehicle because Australia is in the process of adopting Euro 6 in the Australian Design Rules for motor vehicles. As a second stage manufacturer (SSM) JRace can only apply for approval to modify vehicles prior to first registration once IA have their new ADR approval. It's complicated!

Driveshaft.
The driveshaft is the major limitation to ANY suspension lift. The standard suspension travel is set by the shocks. Jay says they're oddly short in length and he suspects this may be to protect the driveshaft. His view is any lift will shorten the life of the rear (T/C) CV because the shaft will contact the mouth of the CV (and pinch the boot) at the bottom of travel. That backs up the numerous failed CVs reported on here. He was not aware of the failed CVs on vehicles with standard suspension or the failed driveshafts due to c-clip separation.

Jay has tested many designs in different combinations of driveshaft joints. He is aware of similar testing done in the USA with mixed results. Jay is at revision 5 of a design that he is not 100% happy with but may need to run with. He was not ready to share what that design is but did say that when it wears out it would be simple and inexpensive to repair. If he cannot further improve the design the owner will need to sign a release so there are no surprises if it has some residual vibration at highway speed or it needs repairs early. This seems to be the development point where others are at also.
His rev 5 shaft has a slight cyclic harmonic at 100-105km/h (~62-65mph). If you want his lift kit you'll need to change your driveshaft and accept that as a cost to ride. You don't need a suspension lift to blast down the highway or go to the mall, and you shouldn't be travelling at highway speeds offroad so the vibe becomes an inconveniece if your vehicle is a daily driver or during high speed transits to your offroad playground. How much time you spend at highway speeds will dictate how long your new driveshaft would last before it needed repair.

Future developments.
Jay's view is there are only two viable long-term solutions to doing a lift and resolving the driveshaft issues: Portal hubs, or a complete redesign of the front axle with new suspension. We don't know if IA will do a Gen II revised platform but there is work going on with portal hubs. Jay is working with 74Weld in the USA on a portal hub solution. A similar setup to the Ineos-backed Letech portals offering but at an affordable price point. Jay understands that IA USA are assisting 74Weld on this project. 74Weld list Grenadier portals dev work in their website FAQ doc here.

There is a middle-ground option and that is a parttime 4WD kit. A parttime 4WD kit means the front driveshaft is not turning unless you engage 4WD. That reduces the duty cycle on the front driveshaft and extends its life. Jay is still very early in exploring the option so I would consider this a thought bubble. He doesn't know if the transfer case or front axle (or software) could support it or if the market would buy it.

Finally, I pointed Jay towards Proformance Motorsports and their extreme angle CVs. Jay had a quick look while we were talking and he got interested enough that he said he would contact Proformance to request a drawing to see if it could fit into the 3D model he has developed.

If you want to keep tabs on JRace you can subscribe to their social channels on their homepage here, bookmark their website and check in occasionally, or send an email to info (at) jraceindustries . com . au and ask to be kept up to date on Grenadier developments.

 

[NQ94]

It's good to see more Australian development work going into the Grenadier.
I can see why the part time 4x4 may only be a thought bubble. The t/case will be the least of the issue, the rear differential size would be more of a concern especially for people that run at increased gvm or are constantly heavy towing. The ring gear is only 220mm not much bigger then a Hilux rear diff. One of the design features of using permanent 4x4 is to decrease the diff size and cost because the drive load is spread over two diffs on a good surface.
The other issue with the part time suggestion is the front drive shaft will always rotate because there is no front axle disconnect available without reengineering the front axles and axle housing and the hub design does not allow for free wheeling hubs to be installed without significant reengineering.

 

[Clark Kent]

It's good to see more Australian development work going into the Grenadier.
I can see why the part time 4x4 may only be a thought bubble. The t/case will be the least of the issue, the rear differential size would be more of a concern especially for people that run at increased gvm or are constantly heavy towing. The ring gear is only 220mm not much bigger then a Hilux rear diff. One of the design features of using permanent 4x4 is to decrease the diff size and cost because the drive load is spread over two diffs on a good surface.
The other issue with the part time suggestion is the front drive shaft will always rotate because there is no front axle disconnect available without reengineering the front axles and axle housing and the hub design does not allow for free wheeling hubs to be installed without significant reengineering.

You're all over it. Jay talked about the parttime option a bit more but I had to stop writing at some point so I just mention it to say that he is doing a deep dig for solutions.

 

[evomind]

It kinda sounds like trading one imperfect solution for another imperfect solution.
Except of course if you are a Rockefeller and just convert the whole thing to portal axles.
Im not sure Im feeling the joy from this "good news."

 

[parb]

Just got to say that I'm thoroughly enjoying this thread. So much good stuff and insights from all corners of the world!

 

[Clark Kent]

It kinda sounds like trading one imperfect solution for another imperfect solution.
Except of course if you are a Rockefeller and just convert the whole thing to portal axles.
Im not sure Im feeling the joy from this "good news."

"No Golden Goose Solution" should have set the tone. I don't think I upsold it?

Understanding a problem helps make progress towards eventually solving it. Even if that means trying things that don't work. As more smart people apply their skills to this we will eventually bracket in on a fix or a liveable compromise in the interim. As I noted above and Jay pointed out several times, Ineos should fix this with a redesign. I won't share what Jay actually said but suffice to say he's frustrated that this has soaked up a lot of time that he won't get back when it's actually a factory problem. He was not complimentary towards Magna or Carraro for what he sees as rookie design mistakes for a rugged adventure vehicle.
One thing was clear. If you want to improve your odds of avoiding problems then stay away from suspension lifts at this point, or go ahead if you really must but do it with both eyes open and get familiar with the drivetrain.