MetalCloak

[Dokatd]

Adding drop brackets to the frame to relocate the suspension links changes a lot of things.

The most obvious is that it partially negates any suspension lift you may have installed.

As well it completely changes the suspension’s geometry. This changes as C-Mack said instant center, anti-dive(front axle) anti-squat(rear axle) etc etc. If you are going to change your suspension like this it’s best to change the frame side mount all together so you can make the links longer. That’s why jeeps have “long arm kits”. In the Land Rover world the first domestic USA kit was the Safari Guard lower link kit for the rear and the infamous 3-link kit for the front. These made the D90 and Disco I much more capable.

But even on rovers you had drive line vs caster issues. Eventually people started rotating their swivel balls etc. to make up for these issues. Double cardan shafts were the answer for the most part though. The Disco II came with a double cardan shaft that swapped into the older trucks and made life much better as we stopped blowing front drive shafts on the highway. Eventually several outfits started making good aftermarket ones.

Anyways, these new IG suspension links are cool and I’m glad someone is getting them out fast. I’m not sold on the need based on geometry alone at this moment, but for strength and durability I’m sure they are great.

 

[Commodore]

The only way that I know of to concurrently correct the caster AND pinion angle when lifting a solid front axle is to do the old “cut and turn”. This is a process where the knuckles are cut free from the axle tube and turned relative to the pinion angle. This allows for correct caster and correct pinion at any given static ride height. It is very common practice on Jeeps and Early Broncos. I have yet to hear of anyone doing this on a Grenny. Perhaps the day will come when someone offers an exchange service. They send you a corrected axle and you send them your stock axle.

Here is a video that explains the process. You might want to fast forward through it.

View: https://youtu.be/Ys1Ds_JH-Hc?si=_U9fa8et-UFYhnKE

 

[angstorms]

Don’t disagree you can add plates and all sorts of things to restore caster but even just going off those drawings my point remains your pinion angle has now changed as well which could cause a driveline vibration due to sharper angles involved depending on the style of driveshafts (u-joint) you are running (less so with CV style). So no free lunch as correcting one problem can lead to some compromises in other areas of the suspension or driveline to watch out for.

I would also think adjustment plates like that change fundamental design elements such as the “instant center” or swing of the 4-link front axle and how it interacts with the unchanged rear axle geometry could create odd handling behavior as the two axles go about their business and react to inputs differently. Maybe not a big issue if you are building a rig optimized for technical trails or hardcore off-roading but worth understanding the physics at play if you are relying on your rig for daily driving as well.

Not saying modifications can’t be beneficial but a solid understanding of the stock geometry and the impact any changes may have to it may be the difference between a safe and predictable handling rig after the modifications.

If you looking what we have now for Caster adjustment on grenadier, the plate would just extend the range of adjustment from the limited range we have today to better match caster what we have as stock when we raise/lift the vehicle. Geometry is first thing we need to address to get back to closer to factory angles so we avoid the issue you raise with vibration and other issue. If you want what they do to raise FJ80 or even old Defender you see they used offset the bushing.

Honestly this is problem with solid axle people have solved with a number of solution so they can lift there truck.

OME bushing for FJ80

Doberson also had bracket to address this issue

even custom control arms on Defender 110

 

[Commodore]

If you looking what we have now for Caster adjustment on grenadier, the plate would just extend the range of adjustment from the limited range we have today to better match caster what we have as stock when we raise/lift the vehicle. Geometry is first thing we need to address to get back to closer to factory angles so we avoid the issue you raise with vibration and other issue. If you want what they do to raise FJ80 or even old Defender you see they used offset the bushing.

Honestly this is problem with solid axle people have solved with a number of solution so they can lift there truck.

OME bushing for FJ80
View attachment 7875841
Doberson also had bracket to address this issue
View attachment 7875842

even custom control arms on Defender 110View attachment 7875843

It isn't difficult to change the caster but then your pinion angle goes to hell. This is especially true on a lifted solid front axle truck.

 

[angstorms]

It isn't difficult to change the caster but then your pinion angle goes to hell. This is especially true on a lifted solid front axle truck.

Yep. Here is good tutorial on Pinion Angle from Tom Wood's https://4xshaft.com/blogs/general-tech-info-articles/driveshaft-angles

 

[CountyV8]

If you looking what we have now for Caster adjustment on grenadier, the plate would just extend the range of adjustment from the limited range we have today to better match caster what we have as stock when we raise/lift the vehicle. Geometry is first thing we need to address to get back to closer to factory angles so we avoid the issue you raise with vibration and other issue. If you want what they do to raise FJ80 or even old Defender you see they used offset the bushing.

Honestly this is problem with solid axle people have solved with a number of solution so they can lift there truck.

OME bushing for FJ80
View attachment 7875841
Doberson also had bracket to address this issue
View attachment 7875842

even custom control arms on Defender 110View attachment 7875843

Arnt terraflex opened by Britpart ??????????

 

[owl (Owl Outdoor)]

Arnt terraflex opened by Britpart ??????????

TerraFlex are owned by Wheel Pros https://www.wheelpros.com/brands/

 

[angstorms]

TerraFlex are owned by Wheel Pros https://www.wheelpros.com/brands/

This is different company Terafirma https://terrafirma4x4.com/pair-of-3-degree-caster-corrected-front-radius-arms-for-def-d1-rrc.html for Landrover Defender

 

[Roving.Grenadier]

Any hints at swaybar disconnects

It's in the pipeline, I have them on my rig. Not sure of the release schedule though.

 

[Roving.Grenadier]

Will we be able to extend the castor from the current 2 degrees?

Yes you will. But make sure all the rest of the geometry and math works before you nuke a CV or pinion.

 

[Beowulf]

It's in the pipeline, I have them on my rig. Not sure of the release schedule though.

Will they be disconnected from the inside, or manually from the outside?

 

[Roving.Grenadier]

Manually from the outside. Easy to access. A disconnect at each end, but only one is necessary to be removed.