I'm glad I came across this video. I have a D1 with a 2" Terrafirma lift done by the previous owner and have been wondering why it steers so twitchy and is terrifying to hit highway speeds. Will definitely be doing this soon.
This shouldn't be a thing that ever breaks but my dad was running 3 degree terrafirma radius arm and one of them completely sheared off, became 2 pieces, since both he and I have put caster correct swivel housings on our defenders, probably better as pinion angle is still the same throughout travel as standard, best would be to use the genuine swivels and get them drilled/machined for caster correction
Yeah, the onroad experience sans sway bars can be pretty darn unnerving!! My wife and I were camping down near Carlsbad, CA & she wanted to run to the store quick in the Disco - She never drives the Disco and because I'm so used to it, I forgot how squirrelly it is without the sway bars and the lift!! (it's also a manual trans) When she got back, she was white as ghost because she attempted to get on the 5 fwy but quickly realized she was going to die if she tried going fwy speeds! So there she was, driving like 45 on the freeway!! Poor thing! 🤦
Hey bro I have a question for you! So I have a D2 and I'm doing the Terra Firma 4-in lift in about 2 weeks. I also have the Johnny Joint 6° adjustable arms on order my question is how do I decide where to set them at? Part of me wishes I had got fixed ones but I only ordered those ones because they have roller bushings and I thought that was cool. So is it logical to measure the factory angles with an angle finder with it both resting on the ground weight of the vehicle on the suspension and also up in the air suspension fully extended and whatever those Factory measurements are just try to meet that in both positions with the adjustable ones? I have a hard time finding info on this but that's the idea I came up with not knowing much about it. Or my second idea is since it's a 4-in lift and usually 6° is recommended maybe I just contact adrenaline 4 x 4 who makes those and ask them at what amount of threading if any of the adjustable part would automatically make them around 6°?? I'm just curious your two cents haha
You must have a D1 mine a 04 D2 the radius arms are different but similar I have a 4in terrafirma lift I'm installing still debating on tire size probably be on 34 or 285 but nobody talks about the rear radius arms on a lifted discovery
Yeah, Mine is a D1. I have another video where I make some adjustable trailing arms to address some issues with the rear suspension after lifting it to fit 35s. But The D1 is a 3-link rear, and I think the D2 has a watts link.
Yeah, based on what the manufacturer recommends, I think 3° arms are fine for a 2" lift. At 3" of lift, I was right between 3 and 6°, and only went with 6 because I may add more lift in the future.
Thank you, please share with your thought on the terrafirma after 9 months? Its interesting, I had similar symptoms to you. But i Solved them with tie rods, steering rod and panhard rods. on defenders with 33" and 25" tyres. Thats why I love LR, no two are the same :)
As far as the radius arms themselves are concerned, I have no complaints at all. They seem plenty strong enough for me. I do think that 6 degrees MAY have been too much, because now with the 4" lift, I get a slight vibration coming from the front under acceleration.
6° feels pretty good to me. I think at 3" lift, we're probably due for somewhere between 3-6°, but if I know myself, there's a good chance I'll go up to 4" springs at some point, so I liked the idea of some extra headroom.
@@tfrasca142 fair point, I too plan to run 35s here in the near future. Thanks for the opinion I think I’ll go 6 degree as well. Thanks for the install video
@@riverbedoverland Hopefully you get 35s on before I do so I can see how much more cutting I'll have to do. I really want to avoid having to use wider arches.
Curious if you experienced any front driveshaft vibrations prior to fitting the new radius arms and if you were running a stock front shaft? Often with the pinion angle change that goes along with caster adjusted arms requires a double cardan front shaft to smooth out any vibrations as the stock front driveshaft u-joints are set out-of-phase deliberately at the factory by several degrees to work with the steeper stock front pinion angle of D1’s and late 90’s RRC’s. Changing to castor adjust arms will tend to lower the front pinion angle which makes the out-of-phase stock shaft vibrate due to u-joint harmonics hence the need to switch to a double cardan unit.
@@andicogthat would have been cool to know. The downside to rotating the whole axle is that it makes the pinion angle theoretically worse for a double cardan shaft. Although I haven’t actually noticed any issues related to that.
@@tfrasca142 I had trouble with noise from my 110 back axle after a 2" lift , only on a neutral throttle, everyone I spoke to said the pinion angle doesn't change with suspension travel, yes, it does! I ended up fitting spacers between the chassis and the trailing arm bushes, it cured it, the spacers are genuine LR, apparently they had trouble on 90 Defenders when fitting H/D suspension at the factory, it upset the pinion angle, even the factory were having trouble! 👍
That's crazy that anyone would tell you the pinion angle doesn't change along with the ride height. The spacers must have been pretty thin, right? There's not too much extra thread on the chassis end of the stock trailing arms.@@andicog
I'm glad you mentioned this. I thought I had torqued everything down, but just went out to check and found the rear axle to radius arm bushing bolt was loose. I looked at the D1 Workshop Manual I have and the value for that fastener is 197 Nm, or about 150 ft lbs. The larger nut holding the rear of the radium arm to the chassis is supposed to be 176 Nm, which I had done. But seriously, thanks for saying something.
@@davidisdivad I hear ya! I carry the boxed end wrench for that nut now, because after a lot of hard wheeling, it can actually come a bit loose after a lot of flexing. I think I even added a lock washer to mine if memory serves correctly
I just went through this last year on my RRC. Every single bolt came out without issue, but one. Nightmare. Keep up the good work!
It seems to always be one bolt, right?
I'm glad I came across this video. I have a D1 with a 2" Terrafirma lift done by the previous owner and have been wondering why it steers so twitchy and is terrifying to hit highway speeds. Will definitely be doing this soon.
Great job! I agree with standard bushes I fit poly to mine purely for ease but I’m gonna fit standard as soon as I get hold of a press
The Harbor Freight 20-ton press I have is one of my favorite tools.
Great work Tyler as per usual 👌🏽!
Thanks 🙏🏻
10/10 washer placement
I’ve been waiting months for this validation.
You make solid videos and deserve more subs 👍
Thanks! I guess I haven't been impressing the algorithm though. 🤷♂
Well when you do, those of us that are here now, just get some bragging rights lol
This shouldn't be a thing that ever breaks but my dad was running 3 degree terrafirma radius arm and one of them completely sheared off, became 2 pieces, since both he and I have put caster correct swivel housings on our defenders, probably better as pinion angle is still the same throughout travel as standard, best would be to use the genuine swivels and get them drilled/machined for caster correction
Yikes, that’s scary. I only just recently learned about caster corrected housings, and I like that idea.
Yeah, the onroad experience sans sway bars can be pretty darn unnerving!! My wife and I were camping down near Carlsbad, CA & she wanted to run to the store quick in the Disco - She never drives the Disco and because I'm so used to it, I forgot how squirrelly it is without the sway bars and the lift!! (it's also a manual trans) When she got back, she was white as ghost because she attempted to get on the 5 fwy but quickly realized she was going to die if she tried going fwy speeds! So there she was, driving like 45 on the freeway!! Poor thing! 🤦
Hey bro I have a question for you! So I have a D2 and I'm doing the Terra Firma 4-in lift in about 2 weeks. I also have the Johnny Joint 6° adjustable arms on order my question is how do I decide where to set them at? Part of me wishes I had got fixed ones but I only ordered those ones because they have roller bushings and I thought that was cool. So is it logical to measure the factory angles with an angle finder with it both resting on the ground weight of the vehicle on the suspension and also up in the air suspension fully extended and whatever those Factory measurements are just try to meet that in both positions with the adjustable ones? I have a hard time finding info on this but that's the idea I came up with not knowing much about it.
Or my second idea is since it's a 4-in lift and usually 6° is recommended maybe I just contact adrenaline 4 x 4 who makes those and ask them at what amount of threading if any of the adjustable part would automatically make them around 6°?? I'm just curious your two cents haha
You must have a D1 mine a 04 D2 the radius arms are different but similar I have a 4in terrafirma lift I'm installing still debating on tire size probably be on 34 or 285 but nobody talks about the rear radius arms on a lifted discovery
Yeah, Mine is a D1. I have another video where I make some adjustable trailing arms to address some issues with the rear suspension after lifting it to fit 35s. But The D1 is a 3-link rear, and I think the D2 has a watts link.
Quick question, my Disco 1 is going to life with 2 inches kit so maybe I need 3 degree radius arms? Thank you
Yeah, based on what the manufacturer recommends, I think 3° arms are fine for a 2" lift. At 3" of lift, I was right between 3 and 6°, and only went with 6 because I may add more lift in the future.
@@tfrasca142Thank you for your help!
Thank you, please share with your thought on the terrafirma after 9 months? Its interesting, I had similar symptoms to you. But i Solved them with tie rods, steering rod and panhard rods. on defenders with 33" and 25" tyres. Thats why I love LR, no two are the same :)
As far as the radius arms themselves are concerned, I have no complaints at all. They seem plenty strong enough for me. I do think that 6 degrees MAY have been too much, because now with the 4" lift, I get a slight vibration coming from the front under acceleration.
@@tfrasca142 Thats interesting, who is lifting the 4 inches? Coils, brackets?
Have you found the 6 degree on a 3” to work well? I was just fixing to order 3 degree today for same height of lift.
6° feels pretty good to me. I think at 3" lift, we're probably due for somewhere between 3-6°, but if I know myself, there's a good chance I'll go up to 4" springs at some point, so I liked the idea of some extra headroom.
@@tfrasca142 fair point, I too plan to run 35s here in the near future.
Thanks for the opinion I think I’ll go 6 degree as well. Thanks for the install video
@@riverbedoverland Hopefully you get 35s on before I do so I can see how much more cutting I'll have to do. I really want to avoid having to use wider arches.
Great looking disco. What’s the tire size?
Thanks! Tires are 255/85r16.
Curious if you experienced any front driveshaft vibrations prior to fitting the new radius arms and if you were running a stock front shaft? Often with the pinion angle change that goes along with caster adjusted arms requires a double cardan front shaft to smooth out any vibrations as the stock front driveshaft u-joints are set out-of-phase deliberately at the factory by several degrees to work with the steeper stock front pinion angle of D1’s and late 90’s RRC’s. Changing to castor adjust arms will tend to lower the front pinion angle which makes the out-of-phase stock shaft vibrate due to u-joint harmonics hence the need to switch to a double cardan unit.
Yup, after I put the lift on, (before radius arms) I had some driveshaft vibrations. A Tom Woods double cardan shaft fixed that.
Here in the UK you can buy castor corrected swivel housings that correct the castor angle without moving the axle.
@@andicogthat would have been cool to know. The downside to rotating the whole axle is that it makes the pinion angle theoretically worse for a double cardan shaft. Although I haven’t actually noticed any issues related to that.
@@tfrasca142 I had trouble with noise from my 110 back axle after a 2" lift , only on a neutral throttle, everyone I spoke to said the pinion angle doesn't change with suspension travel, yes, it does! I ended up fitting spacers between the chassis and the trailing arm bushes, it cured it, the spacers are genuine LR, apparently they had trouble on 90 Defenders when fitting H/D suspension at the factory, it upset the pinion angle, even the factory were having trouble! 👍
That's crazy that anyone would tell you the pinion angle doesn't change along with the ride height. The spacers must have been pretty thin, right? There's not too much extra thread on the chassis end of the stock trailing arms.@@andicog
Hope ya torque them down, I think the rear are supposed to be 170ftlbs
I'm glad you mentioned this. I thought I had torqued everything down, but just went out to check and found the rear axle to radius arm bushing bolt was loose. I looked at the D1 Workshop Manual I have and the value for that fastener is 197 Nm, or about 150 ft lbs. The larger nut holding the rear of the radium arm to the chassis is supposed to be 176 Nm, which I had done. But seriously, thanks for saying something.
You welcome, ask me how I know lol 😂
@@davidisdivad I hear ya! I carry the boxed end wrench for that nut now, because after a lot of hard wheeling, it can actually come a bit loose after a lot of flexing. I think I even added a lock washer to mine if memory serves correctly
What size tires are you running btw?
255/85r16. I like the size, but may try 285/75 next time for the better selection.
285/75r16 is what I'm running on my 94 trooper. 👌🏽 it's a balanced look. But I love your skinnys. Thanks