Front Drive Shaft Update

[TCMColorado]

It is curious that Tom Woods reportedly walked away from making a front shaft for the Grenadier. The two viable options seem to be a shaft with Rzeppa joints on both ends with the one at the transfer case using an accordion style boot which would hopefully be more durable than the OE style boot. Or alternatively a shaft with a Rzeppa at the pinon and a double cardan joint at the transfer case. This configuration would eliminate the problematic boot at the transfer case while not requiring the shaft to be lined up at 90° to the transfer case as would be required by a single cardan u-joint in that location. But not myself being an expert on prop shafts maybe there is a technical reason that neither of these options is viable. In which case the only resolution will be a cut and turn of the OEM axle or a full axle housing replacement either of which would preserve/increase caster while raising up the pinon which would reduce the shaft angle at both the pinon and the tranfer case.

 

[C-Mack]

Could it be some folks have gravitated toward the Grenadier to differentiate themselves from the Jeep, Bronco or even LR crowd? It's a busy owner space for sure and I can easily sympathize with those seeking to try something different or avant-garde, I'll even call myself out on this. If the mission statement is to have the ultimate rock crawler and then try and turn the Grenadier back into what they just stepped away from with the other brands strikes me as a bit of a head scratcher.

Nothing wrong with this approach if you have the budget and can live with the compromises such modifications inherently create. By all means, build the rig you want but if I was looking for a vehicle primarily for technical rock climbing I don't think the Grenadier would be my first port of call. I'm not a big Jeep or Bronco fan per se but I'd certainly take one over a Grenadier if my daily sandbox was Moab, extreme rock trails in Colorado or someplace similar. Stock or OEM+ is enough for me as my personal mission statement is to keep my Grenadier as usable and reliable as possible across mixed uses. I'm certainly not enough of an engineer go much beyond what the Grenadier was ostensibly designed for but I don't want to spoil anyone else's fun either.

 

[Tazzieman]

The sentiments here have been repeated SO many times on this forum I can barely bring myself to fill a 4rd line of text and waste more energy

 

[C-Mack]

I've been to Tom Woods shop in Ogden to have some custom LR driveshafts made. For some perspective, I once tried to have them rebalance an OEM rear drive shaft for an older LR which has the rubber flex-disc and they said, rather bluntly, there is no way for them to set it up in their machines to balance. Their whole shop is built around cardan and double cardan drive shaft solutions so they mainly build components to replace Rzeppa joints. In some respects using Rzeppa's would be going backwards to them. Domestic brands are their bread and butter but they do offer solutions for LR and Toyota as well and grateful for it.

If I was to hazard a guess, the Grenadier is a bit outside their area of expertise and I'm sure any business with as good a reputation as theirs for building reliable components wouldn't want to risk building solutions for such a new platform where they can't guarantee results. The Grenadier does have some unique geometry challenges at the front and that would be very hard issue to work around so why risk a good reputation as a business on a solution you couldn't have absolute confidence in for your customer. I'm sure other drive shaft shops would look at it the same way.

 

[NQ94]

Did Tom Woods walk away from the project not because of engineering issues but because of liability, warranty and legal issues caused by customers expecting Tom Woods to cover warranty after Ineos voids the warranty for possible powertrain damage on a new car caused by an owner fitting non-OEM endorsed modified components?

 

[Dokatd]

Did Tom Woods walk away from the project not because of engineering issues but because of liability, warranty and legal issues caused by customers expecting Tom Woods to cover warranty after Ineos voids the warranty for powertrain damage on a new car caused by an owner fitting non-OEM endorsed modified components?

Tom Woods walked because there is not a viable solution with only a drive shaft change. The angles at the at-Case are too extreme for a Double Cardan. And you can't use the acordian boot at the T-case as all the grease would migrate to the boot and cause balance issues. Also many drive shaft shops are not equipped to balance Rzeppa joint drive shafts. I offered to pay whatever it took to get Tom Woods tooled up for it. I also approached 2 other major US drive line shops including ones that can work with Rzeppa joints. They said it would not work and the best option was to retain the stock setup. But that they all acknowledge the boot might fail over time.

 

[derek0343]

I've been to Tom Woods shop in Ogden to have some custom LR driveshafts made. For some perspective, I once tried to have them rebalance an OEM rear drive shaft for an older LR which has the rubber flex-disc and they said, rather bluntly, there is no way for them to set it up in their machines to balance. Their whole shop is built around cardan and double cardan drive shaft solutions so they mainly build components to replace Rzeppa joints. In some respects using Rzeppa's would be going backwards to them. Domestic brands are their bread and butter but they do offer solutions for LR and Toyota as well and grateful for it.

If I was to hazard a guess, the Grenadier is a bit outside their area of expertise and I'm sure any business with as good a reputation as theirs for building reliable components wouldn't want to risk building solutions for such a new platform where they can't guarantee results. The Grenadier does have some unique geometry challenges at the front and that would be very hard issue to work around so why risk a good reputation as a business on a solution you couldn't have absolute confidence in for your customer. I'm sure other drive shaft shops would look at it the same way.

Yes, I think that's exactly why Tom Woods do not want to work on the Grenadier. The angle on the front diff housing just make really hard for anyone want to make a U joint or double cardon design.

 

[Dokatd]

Yes, I think that's exactly why Tom Woods do not want to work on the Grenadier. The angle on the front diff housing just make really hard for anyone want to make a U joint or double cardon design.

To be clear, I am the one that Tom Woods informed they would not be moving forward with Grenadier development. I was working closely with them for some time and dropped over $1K in trying to help them develop the right shaft. They are involved with the shop that made the shaft for the Bodhis build as well and still dropped out.

So there is no need to speculate as to the reason. They can't work on Rzeppa joint shafts and won't tool up for it even if I paid for the tooling. And Double Cardan joints cannot technically handle the angle when the truck has a minor lift.

Ineos really mucked up pretty well with their front end design.

 

[angstorms]

In that configuration the Ujoint angle has to be zero or near zero. That cannot be done with the Grenadier.

It was not the point, this was about so we can inform the broader non -expert how the Jeep is configured. How it solved Grenadier is another kettle of fish.

 

[Dokatd]

It was not the point, this was about so we can inform the broader non -expert how the Jeep is configured. How it solved Grenadier is another kettle of fish.

Fair enough, I understand. Maybe I didn't read your post thoroughly. My fault

And to answer your question a bit, Tom Woods saw what was going on with one of their suppliers attempts on Bodhis truck and backed out before they even tried.

 

[NQ94]

To be clear, I am the one that Tom Woods informed they would not be moving forward with Grenadier development. I was working closely with them for some time and dropped over $1K in trying to help them develop the right shaft. They are involved with the shop that made the shaft for the Bodhis build as well and still dropped out.

So there is no need to speculate as to the reason. They can't work on Rzeppa joint shafts and won't tool up for it even if I paid for the tooling. And Double Cardan joints cannot technically handle the angle when the truck has a minor lift.

Ineos really mucked up pretty well with their front end design.

Thank you for explaining the process.
I was suggesting the warranty and possible legal action side of things because here in Australia Toyota and other brands are becoming more active in completely voiding warranties on modified new vehicles not just the area of modification. Not sure if this is happening in other parts of the world. Australia there is a massive market for large GVM upgrades, wagon to dual cab conversions and chassis extensions prior to the first registration of a new vehicle. The issue has been who is going to take up the warranty obligations on a modified new vehicle's powertrain. It is currently a grey area with round about vague explainations from the companies modifing the vehicles and dealer service departments saying the OEM are not covering the warranty repair cost.

 

[Dokatd]

Thank you for explaining the process.
I was suggesting the warranty and possible legal action side of things because here in Australia Toyota and other brands are becoming more active in completely voiding warranties on modified new vehicles not just the area of modification. Not sure if this is happening in other parts of the world. Australia there is a massive market for large GVM upgrades, wagon to dual cab conversions and chassis extensions prior to the first registration of a new vehicle. The issue has been who is going to take up the warranty obligations on a modified new vehicle's powertrain. It is currently a grey area with round about vague explainations from the companies modifing the vehicles and dealer service departments saying the OEM are not covering the warranty repair cost.

In the US the theory is the manufacturer has the burden of proof that a modification has done something to void warranty. But even that only voids the warranty for the immediately concerned parts.

That said, there has been a fair number of both modded and stock trucks that have failed driveshafts. But certainly stock trucks shafts are failing at a lower rate seemingly. But I very strongly believe Ineos would win this fight easily. That doesn't change that they screwed up designing the front end on a truck they seemingly claimed would be modification ready. It's just not necessarily their fault the shafts are failing though. That is unless we find they purchased NOS joints that were too aged or someone finds the rubber boots compound is not what they specced from their supplier etc.

 

[Brandtnm]

And I'm sure you would likely be fine on 33's. The majority of rock crawling takes place in the western US deserts, but 90% or more of it is unnecessary to get from point A to B. Don't get me wrong, I love the scenery at "Point B" but I also very much enjoy exploring the limits of my vehicles and myself. And that means more ground clearance.

Places like Moab can be super easy (Think Subaru) or super hard depending on the reason you are there.


View attachment 7891798

He’s right, and grenadiers make getting from A to B so pleasant! Air conditioning, power windows, and chassis by Steyr, etc.

p.s.

and speaking of Steyr chassis, if you’re going to get 2 tires in the air, you should put more on the ground!

 

[Dokatd]

He’s right, and grenadiers make getting from A to B so pleasant! Air conditioning, power windows, and chassis by Steyr, etc.

p.s.

and speaking of Steyr chassis, if you’re going to get 2 tires in the air, you should put more on the ground!
View attachment 7891881

Now I need to find a good pic of my 712.

 

[Zimm]

Having wheeled with 712's, underwhelming is the only word I can use. If I had a choice between that, and say a fantasy 710 with a more appropriate 250hp, I'd take the HP. It seems in anything but dry conditions the massive 90hp spins those wheels just enough to replicate a cat burring a it's turd on a marble floor.

 

[Fab]

Im not sure if I would want to take my TGB rockcrawling.
They tend to tip over easily, but it´s a lot of fun driving.
And after driving one of those, the Grenadier is sheer luxury..

@Dokatd Where did you get the parabolics from?

 

[Dokatd]

Having wheeled with 712's, underwhelming is the only word I can use. If I had a choice between that, and say a fantasy 710 with a more appropriate 250hp, I'd take the HP. It seems in anything but dry conditions the massive 90hp spins those wheels just enough to replicate a cat burring a it's turd on a marble floor.

Thus why I ultimately sold mine. It was fun in Moab and ok in Las Cruces, but not just amazing in any way.

 

[Dokatd]

TGB will get your blood flowing for sure.

View: https://youtu.be/PA3jEoGPPfc?si=jgB3B6Dyx1lLTmHn

 

[Zimm]

Thus why I ultimately sold mine. It was fun in Moab and ok in Las Cruces, but not just amazing in any way.

It's an emotional letdown. Ya look at it and think it's going make fools of the rest of us by crawling up everything like a d20 dozer, and you end up breaking out the bubba rope because it's pirouetting on wet roots.

Maybe with 1.5t of ammo crates in the rear, it's a different story.

 

[Dokatd]

It's an emotional letdown. Ya look at it and think it's going make fools of the rest of us by crawling up everything like a d20 dozer, and you end up breaking out the bubba rope because it's pirouetting on wet roots.

Maybe with 1.5t of ammo crates in the rear, it's a different story.

The pirouetteing was a feature on rock ledges. Kinda fun. You go from a massive wheel base to a tiny wheel base instantly and can out maneuver a lot of vehicles. But sadly that wasn't enough to make it in my stable. I may get a 710 someday just to have.