Front drive shaft broken

[C-Mack]

With the small amount of pinion angle correction needed to spare the CV joints I'm wondering why that wasn't built in at the start? Did Carraro have a restriction on the pinion angle? Our vehicle tracks pretty darn well (was driving at 80mph/130kph this afternoon) but our front pinion angle is pointing down enough to be concerning and there's a bit of resonance at higher rpm. I need to inspect the caster bolts to see if the housing has been rotated to provide the better tracking at the expense of the CVs.



And the Grenadier is a full-time system meaning you're always spinning both the front and rear prop shafts. That's largely an unfamiliar arrangement in the States. Most solid axle vehicles here allow for rear drive only when highway miles are driven. Part-time hides a multitude of problems that the mall-crawling average purchaser will never encounter.




Ineos' concern is whether or not unlifted vehicles are exhibiting issues in number. If so and this isn't addressed/resolved during the warranty period then a cut and turn may become de rigueur to retain any usefulness in these vehicles. Fortunately the Carraro pinion gear does seem long - much longer than a Dana 44. It wouldn't take more than a few degrees of upward rotation to swing the CV up into an acceptable range. At least we don't have to match angles like with universal joints.

One consideration on how far they can pivot the pinion up probably has to do with the clearance between the diff/pinion and oil sump. If you look under your vehicle even in its stock configuration and imagine the axle articulating upwards the pinion housing and driveshaft gets very close to those components. My guess is this is a limitation on how far they could ultimately tilt it up so very much a packaging consideration for leaving enough space for full axle articulation.

To my mind the only modification, if you absolutely must have a lift over stock height, would be to get custom driveshaft with “high” angle larger Rzeppa joints. It would be a cobbled together deal with custom parts but at least you’d still be running a CV style joint hopefully preserving the smoother ride. You’d have all the same concerns of caster adjustments and don’t forget all the driveshaft angles on the Grenadier are compound angles so both vertical and horizontal. None of the pinions and output shafts line up in a straight line hence why they chose Rzeppa joints in the first place.

All the larger high angle Rzeppa joints would gain you would be a bit more time between a driveshaft overhauls and just thinking about all that work and expense says remaining stock is best option and use the vehicle within it’s factory designed limits which honestly is still plenty of fun to be had.

 

[DaneJa]

Another (very expensive) option would be to maintain all the stock suspension geometry and install portal axles. I know LeTech engineered some and Jay at Dirtbox Overland/Couch Offroad is working on some.

 

[Logsplitter]

For those considering a suspension lift , here is my front prop shaft at full suspension drop

whilst on the lift at the Ineos dealership, well within acceptable levels but with an added suspension lift the CV joint may be at too extreme an angle

 

[LeeroyJ]

For those people that have had the drive shaft failure and have a lift, has Ineos denied warranty coverage? If so, was it in the US or some other country?

 

[LeeroyJ]

For those considering a suspension lift , here is my front prop shaft at full suspension drop View attachment 7870008whilst on the lift at the Ineos dealership, well within acceptable levels but with an added suspension lift the CV joint may be at too extreme an angle

I don't know why the design has the exit from the diff at an angle that is so close to parallel with road - it seems like if the axle had been designed so that the exit from the diff was tilted so that better aligned with the angle from the drive shaft, that would have put a lot less stress on the system. I wouldn't think that the axel cares if the diff is angled upward, does it?

 

[bamanuke]

For those people that have had the drive shaft failure and have a lift, has Ineos denied warranty coverage? If so, was it in the US or some other country?

out of pocket for me. dealer just said that because of the modification(lift) it wasn't covered. didn't pursue it further.

 

[PNW_IG]

For those considering a suspension lift , here is my front prop shaft at full suspension drop

whilst on the lift at the Ineos dealership, well within acceptable levels but with an added suspension lift the CV joint may be at too extreme an angle

According to Eibach, full extension is controlled by shock travel, not by the spring. If this is true, the spring lift should not exacerbate the problem correct?

 

[TCMColorado]

According to Eibach, full extension is controlled by shock travel, not by the spring. If this is true, the spring lift should not exacerbate the problem correct?

The total range of operating angle for the drive shaft does not change but after installing the Eibach springs the shaft runs continuously at a higher angle than when at the stock height. The theory is that this overheats the CV boot (when driving at highway speeds) which causes it to fail, then the grease flings out and that causes the joint to fail.

 

[PNW_IG]

The total range of operating angle for the drive shaft does not change but after installing the Eibach springs the shaft runs continuously at a higher angle than when at the stock height. The theory is that this overheats the CV boot which causes it to fail then the grease flings out and that causes the joint to fail.

@TCMColorado thanks for the explanation.

 

[anand]

According to Eibach, full extension is controlled by shock travel, not by the spring. If this is true, the spring lift should not exacerbate the problem correct?

This is true, however, it is spending more time at a steeper angle because the ride height is different than stock

 

[Logsplitter]

According to Eibach, full extension is controlled by shock travel, not by the spring. If this is true, the spring lift should not exacerbate the problem correct?

Agreed.

 

[TCMColorado]

This is true, however, it is spending more time at a steeper angle because the ride height is different than stock

Yes the taller ride height increases the steady state angle of the CV joint. At highway speeds this can overheat the CV boot. If the boot remains intact then this increased angle is not likely to cause an issue as the CV joint is still within its operational limit. The question is why some owners are experiencing boot failure and others are not.

 

[Catpaw4x4]

For those considering a suspension lift , here is my front prop shaft at full suspension drop View attachment 7870008whilst on the lift at the Ineos dealership, well within acceptable levels but with an added suspension lift the CV joint may be at too extreme an angle

That angle (long term) just looks scary to me. From an orthopedic standpoint just not good for longterm function.

 

[255/85]

One consideration on how far they can pivot the pinion up probably has to do with the clearance between the diff/pinion and oil sump. If you look under your vehicle even in its stock configuration and imagine the axle articulating upwards the pinion housing and driveshaft gets very close to those components. My guess is this is a limitation on how far they could ultimately tilt it up so very much a packaging consideration for leaving enough space for full axle articulation.

There's some nonsense above the front differential pinion to be sure (fuel lines, oil sensor wires, maybe even the engine oil pan itself) but there's not a lot of uptravel in the front suspension. On early vehicles the rear flexed better than the front by a good deal. I don't know if that's still true. There's only an inch or two before the front bump stops start coming into play. Maybe there's room for a better pinion angle
on lifted vehicles if the stops are set correctly but now we're into the work and expense you mention for a modest gain. Fender hack anyone?

I don't know why the design has the exit from the diff at an angle that is so close to parallel with road - it seems like if the axle had been designed so that the exit from the diff was tilted so that better aligned with the angle from the drive shaft, that would have put a lot less stress on the system. I wouldn't think that the axel cares if the diff is angled upward, does it?

See above. There's also some concern for pinion bearing oiling if the angle is too high.

For those considering a suspension lift , here is my front prop shaft at full suspension drop whilst on the lift at the Ineos dealership, well within acceptable levels but with an added suspension lift the CV joint may be at too extreme an angle

Are they standing by the installation/manufacturing defect as the cause for your CV failure?

 

[LeeroyJ]

out of pocket for me. dealer just said that because of the modification(lift) it wasn't covered. didn't pursue it further.

Do you know if the dealer rejected it or did they actually submit it to Ineos corporate who rejected it? I once had a dispute with a Toyota Dealer in Houston who refused to cover a blown CV joint blaming it on the lift kit I had (which was a lift kit they also sold and installed). I spent months arguing with them before I learned that they had never actually sent it to Toyota corporate for a decision. Corporate approved the warranty claim.

 

[bamanuke]

Do you know if the dealer rejected it or did they actually submit it to Ineos corporate who rejected it? I once had a dispute with a Toyota Dealer in Houston who refused to cover a blown CV joint blaming it on the lift kit I had (which was a lift kit they also sold and installed). I spent months arguing with them before I learned that they had never actually sent it to Toyota corporate for a decision. Corporate approved the warranty claim.

I do not. I initiated a "ticket" with Ineos right after it failed. They(Ineos) wanted to make sure the dealer was involved and could look at the truck. I have not heard back from Ineos in ~2 weeks. I'll call the dealer tomorrow and pose the question. I did ask the dealer on a couple of occasions if they had been in contact with Ineos and they had not.

 

[C-Mack]

I don't know why the design has the exit from the diff at an angle that is so close to parallel with road - it seems like if the axle had been designed so that the exit from the diff was tilted so that better aligned with the angle from the drive shaft, that would have put a lot less stress on the system. I wouldn't think that the axel cares if the diff is angled upward, does it?

It's parallel to the road in stock form to maintain enough caster at the steering knuckles to help keep the steering stable. To raise the pinion any higher would push the caster to near zero degrees or worse into the negative range making the Grenadiers already somewhat vague steering even worse. To raise the pinion and maintain enough caster angle the axle would have to be modified and the steering knuckles orientation changed relative to the pinion to keep all the alignment geometry correct. But in theory I agree, it seems like Ineos could have given the pinion a slightly higher angle and orientated the steering knuckles with slightly more negative caster to compensate thus keeping everything in check.

 

[Logsplitter]

There's some nonsense above the front differential pinion to be sure (fuel lines, oil sensor wires, maybe even the engine oil pan itself) but there's not a lot of uptravel in the front suspension. On early vehicles the rear flexed better than the front by a good deal. I don't know if that's still true. There's only an inch or two before the front bump stops start coming into play. Maybe there's room for a better pinion angle
on lifted vehicles if the stops are set correctly but now we're into the work and expense you mention for a modest gain. Fender hack anyone?



See above. There's also some concern for pinion bearing oiling if the angle is too high.



Are they standing by the installation/manufacturing defect as the cause for your CV failure?

As far as I could understand when I asked a couple of days back it was the C-clip that locates the CV joint onto the shaft coming from the transfer box that failed . What caused the failure whether manufacture or assembly I don’t know.

 

[Clark Kent]

As far as I could understand when I asked a couple of days back it was the C-clip that locates the CV joint onto the shaft coming from the transfer box that failed . What caused the failure whether manufacture or assembly I don’t know.

If this JK CV driveshaft is similar, the snap ring/c-clip is installed on the driveshaft spline after the CV to retain the CV on the driveshaft.
Watch this YouTube from the 9:00 mark. He disassembles the joint and removes the snap ring. He then beats on the CV with a hammer and chisel before using a puller to remove the CV from the spline.

 

[255/85]

If this JK CV driveshaft is similar, the snap ring/c-clip is installed on the driveshaft spline after the CV to retain the CV on the driveshaft.
Watch this YouTube from the 9:00 mark. He disassembles the joint and removes the snap ring. He then beats on the CV with a hammer and chisel before using a puller to remove the CV from the spline.

It's not uncommon for axle components to need a little persuasion to come apart.

What caught my attention was the second sentence out of the reviewer's mouth...

"Now, the Rzeppa joint on the JK is probably one of the most failed components for a couple of different reasons, one being if you have lifted your Wrangler and have not upgraded the drive shaft, the harder angle will wear out the boot over time, which can fling grease and allow dirt in and debris in to damage the joint, especially if you take your Jeep off-road. Now, it can also just fail due to normal wear and tear and age."