Front drive shaft broken

[Commodore]

They specifically said the DC would not handle the angles. I sent them all the angles of my driveline. They then said the Rzeppa can handle more angle than the DC. Which is accurate by the books. But they qualified it all with the Rzeppa boot is maxed out so failure is eminent.


Certainly an option. Not as cost effective if we can get a core axle to cut and turn. Someday we will see a Gren on 60's but that might be awhile. I suspect Ineos will correct the front pinion angle some day. They likely will run through their first batch of axles before though.

It does appear that the Rzeppa isn’t maxing out its working angle mechanically but rather the boot is ripping and that leads to failure. Axle half shafts on independent suspension trucks run Rzeppa joints at more acute angles without failing BUT they use a large external boot instead of the small captive one that we all have. I’m wondering if there is a boot that we can slide over the existing Rzeppa and fill with grease. That way it won’t matter if the inner captive boot rips and spills grease. A larger boot with bellows will handle the repeated flexing much better that that tiny captive boot. Obviously this is why they are used on front axle half shafts that need manage both suspension travel AND steering angle inputs constantly. Hell, I wonder if this isn’t going to be the “new CV” that we are promised for the 2025 model year.

Something like this:

 

[Dokatd]

It does appear that the Rzeppa isn’t maxing out its working angle mechanically but rather the boot is ripping and that leads to failure. Axle half shafts on independent suspension trucks run Rzeppa joints at more acute angles without failing BUT they use a large external boot instead of the small captive one that we all have. I’m wondering if there is a boot that we can slide over the existing Rzeppa and fill with grease. That way it won’t matter if the inner captive boot rips and spills grease. A larger boot with bellows will handle the repeated flexing much better that that tiny captive boot. Obviously this is why they are used on front axle half shafts that need manage both suspension travel AND steering angle inputs constantly. Hell, I wonder if this isn’t going to be the “new CV” that we are promised for the 2025 model year.

Something like this:

View attachment 7887690

Problem is RPM's. Half shafts spin much slower than driveshafts. The larger boot would likely induce some vibrations. It also wouldn't retain all the grease in the joint. The joints get loose primarily due to lack of grease when the boot fails. Dirt etc doesn't help either of course.

 

[Commodore]

Problem is RPM's. Half shafts spin much slower than driveshafts. The larger boot would likely induce some vibrations. It also wouldn't retain all the grease in the joint. The joints get loose primarily due to lack of grease when the boot fails. Dirt etc doesn't help either of course.

How about redesigning the existing boot and retainer. What we are looking for is a high speed CV with a larger and more flexible boot.

We currently have something like this:

And we need something more like this:

I'm going to drop by my local custom driveshaft shop and get their thoughts.

 

[Commodore]

Perhaps it is worth reaching out to these guys and seeing if they would be interested in designing an improved boot.

Drive Shaft CV Boots | High Performance Components | Race-Tec

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Take a look at the attached pdf's.

 

[C-Mack]

Agreed a much tougher boot design would be better but the OEM style is designed to keep the grease as close to the CV bearings as possible (except when it splits open of course) where as a ribbed design would work as a collection point for the grease and not allow it to find its way back into the CV joint.

Maybe on the diff end where the boot would sit higher grease could move back into the joint but on the transfer case end the boot would always be lower than the joint therefore the grease would tend to sit in the boot.

 

[Jhellweg]

Apologies if this approach has already been discussed, but my INEOS dealership who did the Eibach install lowered the differentials, presumably to improve the angle. These are the installation notes from them:

“Removed front and rear driveshaft couplings at differentials to avoid stressing joints. Lowered differentials and replaced springs with spring tool. Reassembled and adjusted front thrust adjustment bolts to maximum value forward.”

Potential improvement? This was for the 2.5/1.2 lift but I had them swap for the 1.7 because I prefer the stance and tow often.

 

[Dokatd]

Apologies if this approach has already been discussed, but my INEOS dealership who did the Eibach install lowered the differentials, presumably to improve the angle. These are the installation notes from them:

“Removed front and rear driveshaft couplings at differentials to avoid stressing joints. Lowered differentials and replaced springs with spring tool. Reassembled and adjusted front thrust adjustment bolts to maximum value forward.”

Potential improvement? This was for the 2.5/1.2 lift but I had them swap for the 1.7 because I prefer the stance and tow often.

They did not do what you are thinking they did.

 

[Jhellweg]

They did not do what you are thinking they did.

Good to know. Would you mind expanding?

 

[Tenac]

Good to know. Would you mind expanding?

Meaning they supported the driveshaft and then lowered the axel down to swap the springs. Basically the exact process one should take to do this, some shops try to save time and leave everything connected and that is what stresses the angle of the driveshafts. I've been checking mine often since my lift so far about 1500miles to indication of damage to the rubber covers.

 

[Jhellweg]

Meaning they supported the driveshaft and then lowered the axel down to swap the springs. Basically the exact process one should take to do this, some shops try to save time and leave everything connected and that is what stresses the angle of the driveshafts. I've been checking mine often since my lift so far about 1500miles to indication of damage to the rubber covers.

Appreciate the explanation. And here I am thinking they had introduced a differential drop for our IGs. Well I’ll be keeping an eye on the boots and hoping the 1.7 lift isn’t too much of an extra strain to put me at risk—so far so good

 

[C-Mack]

I think the “maximum adjustment forward” statement on the paperwork means they dialed in maximum caster after the lift to help with the steering but in effect this lowers the pinion even more adding additional angle to the cv joints. That’s what I’d be more worried about as the cv joints boots are already stressed now they are even more so. Nice of them to baby the driveshafts during install, which is the right thing to do, but now the front is set to run in a condition that will shorten the cv boot life.

 

[Dokatd]

I think the “maximum adjustment forward” statement on the paperwork means they dialed in maximum caster after the lift to help with the steering but in effect this lowers the pinion even more adding additional angle to the cv joints. That’s what I’d be more worried about as the cv joints boots are already stressed now they are even more so. Nice of them to baby the driveshafts during install, which is the right thing to do, but now the front is set to run in a condition that will shorten the cv boot life.

Yeah, you need to make sure the caster is reset after lifting. If you get your caster maxed out at stock height and then lift then you will have even more caster once lifted. So it could be dialed back a bit.

 

[Commodore]

This is a driveshaft for a Jeep Cherokee. Notice the boot design for the transfer case side. Makes me think that we should be looking for something like this.

 

[Jhellweg]

Yeah, you need to make sure the caster is reset after lifting. If you get your caster maxed out at stock height and then lift then you will have even more caster once lifted. So it could be dialed back a bit.

The caster was adjusted forward as a part of the lift to match the guidance that Eibach provides for the IG. Now that potentially adding additional strain is news to me

 

[C-Mack]

The caster was adjusted forward as a part of the lift to match the guidance that Eibach provides for the IG. Now that potentially adding additional strain is news to me

Yup, it’s an unfortunate result of some “interesting” design decisions on the front axle by IA related to suspension geometry, pinion, and caster angles, etc... The current setup is not very forgiving of taller lifts and tends to punish the front driveshaft, more specifically the protective CV boots, which can and have failed on various owners vehicles.

Some possible options are:

• Check the front driveshaft on a regular basis to catch a failure as early as you can
• Return the vehicle to stock configuration to get as much life out of the driveshaft as you can “hopefully”
• Try an aftermarket CV Joint and see if you can get bit more life out of the rubber boot before it fails
• Mess around with various u-joint double/double cardan driveshaft setups and deal with vibrations at speed
• Buy another stock front shaft and have it as a spare and replace it when a joint fails
• Get really lucky (as some have) and not suffer any failures “fingers crossed approach”
• Try to be comfortable with the knowledge that this can be a common failure point especially with a lift and just get on with life
• Hope IA comes up with an improved design or driveshaft but the likely hood of that being a retroactive fix is practically nil.

 

[Ovrland Bill]

Can the integrity of the driveshaft boots on a stock Grenadier be confirmed by a simple visual inspection, or is there more to it than that (such as a component disassembly requirement)?

 

[C-Mack]

Can the integrity of the driveshaft boots on a stock Grenadier be confirmed by a simple visual inspection, or is there more to it than that (such as a component disassembly requirement)?

Yes, very easily in fact. The protective boots are out in the open just slide under the vehicle with a flashlight and closely inspect each boot cv joint closely. Take a damp rag and gentle wipe out each boot cup so you can clearly see the boot material. Look for micro cracking or small tears. It will usually start in a ring near where the boot is bonded to the thinner part of the driveshaft as it enters the joint and sees the most flex during each rotation cycle.

I inspect mine every couple of weeks especially after being off road and in muddy conditions where mud can dry on the surface of the boot. Keeping the boots clean and debris free is a pain for sure but until something more durable comes along it’s the only way I can see to stay ahead of a failure.

 

[Ovrland Bill]

Yes, very easily in fact. The protective boots are out in the open just slide under the vehicle with a flashlight and closely inspect each boot cv joint closely. Take a damp rag and gentle wipe out each boot cup so you can clearly see the boot material. Look for micro cracking or small tears. It will usually start in a ring near where the boot is bonded to the thinner part of the driveshaft as it enters the joint and sees the most flex during each rotation cycle.

I inspect mine every couple of weeks especially after being off road and in muddy conditions where mud can dry on the surface of the boot. Keeping the boots clean and debris free is a pain for sure but until something more durable comes along it’s the only way I can see to stay ahead of a failure.

So it’s just like my LRRP (Land Rover Reliability Program): “Watch it like a Hawk”

 

[GN4HIR]

Has anyone seen the new Wolfbox G900 Pro-IGD (Ineos Grenadier Driveshaft)? It is like the standard G900 Pro but comes with a 3rd camera and mounting bracket to aim it directly at the CV boot. It automatically displays and records, in vivid 4K slow motion, the first 2 (up to 8, user selectable) rotations of the driveshaft every time you start and move the vehicle.

I guess it is a good thing I have my stock springs. Hard to believe 2.5" is that big a deal (that's what she said).

 

[Tazzieman]

Has anyone seen the new Wolfbox G900 Pro-IGD (Ineos Grenadier Driveshaft)? It is like the standard G900 Pro but comes with a 3rd camera and mounting bracket to aim it directly at the CV boot. It automatically displays and records, in vivid 4K slow motion, the first 2 (up to 8, user selectable) rotations of the driveshaft every time you start and move the vehicle.

I guess it is a good thing I have my stock springs. Hard to believe 2.5" is that big a deal (that's what she said).

We've clearly come a long way since Series Land Rovers , where to daily inspect the propshaft you just waited for the handbrake boot cover to perish.
Thereby exposing the rotting rubber gaiter on the propshaft...