80 series caster problem

[stvrn6]

I purchased this project 1997 land cruiser that i just finished working on. I took it on the highway and its very unstable. The steering seems to very jerky. The steering wheel is also not straight either its a few degrees to the right to go straight as well as has a ton of free play.
I'm running Eibach shocks with OME heavy springs front and rear due to extra load. i went to get an alignment to get a base line for my caster and its showing -2 left and -1.9 right. Do i get a 4 degree correction plat or 2? Im just asking since the 4+ correction is recommended for 4+ inch lift and im runnin 2-3 in lift. should i do bushings or plates?
edit: running 315s r17

 

[oilbrnr]

I bit the bullet a couple of months ago and bought the DVS loaded arms and rear panhard relo. After 10+ years of OME offsets, what a difference. Quieter, smoother, softer. Better straight-line stopping, plus the obvious steering/handling improvement from the caster. That said, I've also just replace all the front and rear suspension bushings with OEM. The rear can get pretty sloppy too over time, there's 10 bushings back there...

 

[Nay]

Keep in mind that you are choosing caster here, but on an AWD vehicle, caster has to follow pinion angle or you are likely to get driveline vibrations. The 80 series is unique in that the front driveshaft is OEM configured in a ‘broken back’ alignment, which means the pinion is pointing upwards more than would be typical. The beauty of this is that you can convert to a double cardan driveshaft, and without doing anything else, you have to lower the pinion to create axle end u-joint alignment. Lowering the pinion increases caster, which of course is why lifting without other modifications decreases it.

If you just pick caster, and you leave the stock driveshaft configuration, you are unlikely to have good driveshaft angles in terms of avoiding vibration at higher speeds. The stock setup has people reporting various results that in the world of how u-joint angles operate makes little sense (should vibrate, reported to be fine) but leading with caster when alignment is from the pinion angle is a crap shoot.

Landtank’s plates are unique in that they don’t just drop the bracket, but install in alignment to the factory brackets while drilling new holes. They are difficult to install due to tight spaces using a right hand drill but are a great solution. I am going to drop some massive controversy on your thread and show how I am using stock radius arms with Landtank plates and a DC driveshaft with proper angles and fit 38” tires up front without trimming the fenders or restricting up travel. I have no idea what my caster numbers are because they don’t matter - if I misalign my driveshaft it vibrates, to the point that I run one OME bushing upside down to get it properly aligned. Pics tell the story.

This is my original set beside the higher caster set after grinding/prying off the welds. You are drilling through those pilot holes, not just dropping the brackets like typical caster brackets.

You should weld them, easy enough to get back off if you ever should want to.

This is how the radius arms align. For anybody who plans to keep radius arms and wheel hard, notice how on 5.5” of lift the arms are basically flat under the angle and will act as a slider - this is an ideal setup vs a large bend to drop a radius arm under the tierod. Which brings us to tierod clearance - I have a larger diameter heavy duty Slee tierod and everything clears to pinion and arms without any grinding of the arms. Notice the pinion angle alignment for a double cardan driveshaft (no u-joint angle at the pinion).

 

[Nay]

This is what coil spring alignment looks like - no bow to the front coils.

38” Patagonia MT.

No rubbing at crank and stuff.

Tierod clearances at full flex - just under the pinion and just over the radius arm. Again, I don’t have any radius arm grinding.

You aren’t just bolting this up, but you are retaining factory configuration and optimizing your radius arm functionality while properly setting pinion angle for the preferred double cardan solution to maximize caster.

 

[mudgudgeon]

I'll take minor driveline vibrations and stable handling over a DC shaft and ****ed up caster every day of the week.

At 2-3" of lift, there may not be any serious vibration.
Comparing solutions with a 2-3" lift with solutions for 5.5" lift is not really relevant.

At 5.5" of lift, you're a long way from stock configuration. You've compromised stock configuration in many ways.

 

[Nay]

Here’s a few bit of performance. This spot wants to unload the front and flop you into the rock like in the pic - nicely balances and flexes through.

For the flex doubters on 38’s.

And keeping stable while screwing up, in slo-mo. Can’t recommend dual rate coils, Timbren bumpstops, and no swaybars highly enough.



Hope that helps with some decision making. Best part about this is it’s pretty damn light on your wallet.

 

[Nay]

I'll take minor driveline vibrations and stable handling over a DC shaft and ****ed up caster every day of the week.

That’s exactly what people need to understand. I won’t take driveline vibrations, have zero tolerance for it because for me it ruins the driving experience. I have decel vibes on the stock rear driveshaft because I went to the higher lift and am running dead on the max 10 degree operating angle generally noted as acceptable. Not doing a DC back there without cutting and relocating the spring perches and it’s fine because it is not persistent at speed. This thread was pretty deep into decision making before anybody even mentioned the u-joint angle problem because this forum always leads with caster figures and how you can spend your money on things that rotate the axle without considering that this isn’t neutral to how u-joints operate.

My rig points nicely down the road, but…and this is a major caveat…I have gotten more than expected correction from each set of Landtank’s brackets. We’ve talked about this and seen it in a few rigs over time - I may be a lucky one who had more factory caster than spec. I run one OME bushing in reverse to correct for this, which has an added benefit of increasing tierod clearance. That was after about a decade of use and when I thought I might try a rubber version (on the left before pressing it back out when doing a bushing refresh) before reading they fall apart immediately.

I am showing how the Landtank brackets work here as the art of the possible - it is a seriously difficult install and you need various drill bit types and a right hand drill to work in very tight spaces, but the outcome is worth it. We see quite a few rigs with front fender trimming just to fit 37’s and that is on the backend of spending a lot of money chasing caster.

The stock radius arms can be made to work exceptionally well - an outcome of little to no bend below the tierod for maximum clearance and slider effect without emptying the wallet is a great design goal that can easily provide factory spec caster on a lower lift with zero vibes using a DC driveshaft. My setup is beyond the point of this thread, but the basic concepts of pinion angle alignment and clearances run up and down the stack.

I’ve never understood the amount of caster talk on this forum going on two decades. The 80 is the only rig where you can gain caster just by swapping out to a preferred front driveshaft style and all you have to do from there is align the pinion. The amount of solutions looking for problems around here is unreal.

 

[mudgudgeon]

That’s exactly what people need to understand. I won’t take driveline vibrations, have zero tolerance for it because for me it ruins the driving experience. I have decel vibes on the stock rear driveshaft because I went to the higher lift and am running dead on the max 10 degree operating angle generally noted as acceptable. Not doing a DC back there without cutting and relocating the spring perches and it’s fine because it is not persistent at speed. This thread was pretty deep into decision making before anybody even mentioned the u-joint angle problem because this forum always leads with caster figures and how you can spend your money on things that rotate the axle without considering that this isn’t neutral to how u-joints operate.

My rig points nicely down the road, but…and this is a major caveat…I have gotten more than expected correction from each set of Landtank’s brackets. We’ve talked about this and seen it in a few rigs over time - I may be a lucky one who had more factory caster than spec. I run one OME bushing in reverse to correct for this, which has an added benefit of increasing tierod clearance. That was after about a decade of use and when I thought I might try a rubber version (on the left before pressing it back out when doing a bushing refresh) before reading they fall apart immediately.

View attachment 3699780

I am showing how the Landtank brackets work here as the art of the possible - it is a seriously difficult install and you need various drill bit types and a right hand drill to work in very tight spaces, but the outcome is worth it. We see quite a few rigs with front fender trimming just to fit 37’s and that is on the backend of spending a lot of money chasing caster.

The stock radius arms can be made to work exceptionally well - an outcome of little to no bend below the tierod for maximum clearance and slider effect without emptying the wallet is a great design goal that can easily provide factory spec caster on a lower lift with zero vibes using a DC driveshaft. My setup is beyond the point of this thread, but the basic concepts of pinion angle alignment and clearances run up and down the stack.

I’ve never understood the amount of caster talk on this forum going on two decades. The 80 is the only rig where you can gain caster just by swapping out to a preferred front driveshaft style and all you have to do from there is align the pinion. The amount of solutions looking for problems around here is unreal.

Many ways to skin a cat.

What you are suggesting, a DC front shaft is necessary from the get go?

With 2-3" lift, a DC shaft may never be necessary.

I see what you're saying. Your method requires the commitment to a DC shaft from the start, where as many/most that do a 2-3" lift either don't need a DC shaft, or hope to avoid it.

Aside from initial cost, it's another custom part, and DC joints tend to wear quicker.

Caster equals safety of all passengers in the vehicle.
Vibration if present equals phyisical annoyance

 

[Nay]

Many ways to skin a cat.

What you are suggesting, a DC front shaft is necessary from the get go?

With 2-3" lift, a DC shaft may never be necessary.

I see what you're saying. Your method requires the commitment to a DC shaft from the start, where as many/most that do a 2-3" lift either don't need a DC shaft, or hope to avoid it.

Aside from initial cost, it's another custom part, and DC joints tend to wear quicker.

Caster equals safety of all passengers in the vehicle.
Vibration if present equals phyisical annoyance

DC is not necessary ever, but it is a gift since we have a unique rig where you can offset the caster reduction of quite a bit of lift for nothing other than a swap. The amount of torture people have put themselves through in the archives here by not running as fast as they can to something other platform enthusiasts would kill to have is legendary. 2.5”-3” lifts are a no-mans land when 4” optimizes perfectly without forcing any re-engineering of anything.

I bought a junkyard DC off a first gen Tacoma with 125K miles on it for $120 and had my driveline shop retube for length. That’s been running flawlessly for something like 17 years and 160K additional miles on my 80.

Having less responsive steering - meaning avoiding snappy surprises - isn’t a bad thing. I hugely favor dual rate coils because they act like swaybars without the snap as long as you haven’t added a ton of weight to your rig, and any type of progressive bumpstop is money. Timbren for $500 is a game changer once you dial them in.

Here’s a vid with some slo mo and some stupidity when I was first testing out the setup. That first part is rutting out and bumped, and the last part is a good way to roll if you don’t have a stable design.



I encourage anybody to post up vid of hitting an angled driveway at speed to show how your suspension performs. Wear a helmet if you need to.



And in slo-mo.

https://vimeo.com/567722184

 

[mudgudgeon]

Not everyone wants 4" lift.

I've had an 80 with 4" lift. It was fairly well sorted.
I've had a 105 with 2" lift. It went everywhere the 4" lifted 80 did, and then some.

I wouldn't do a 4" lift again

 

[SNLC]

Not everyone wants 4" lift.

I've had an 80 with 4" lift. It was fairly well sorted.
I've had a 105 with 2" lift. It went everywhere the 4" lifted 80 did, and then some.

I wouldn't do a 4" lift again

Depends on tire size.

I have said it before and I will say it again, there is some weird voodoo with my radius arms. I have 4* on my pinion, zero vibes without a DC shaft and I have 5* of caster. Still not sure I believe the caster number but I have checked it with a 4ft level. Have not had my truck on a different alignment machine though to verify for sure. It does drive like it has that much caster. My shocks are to short currently but it does stuff to the max with them which up travel is more important for go fast off road. My Cruiser eats just about everything I throw at it for go fast off road, within reason. Cattle guard at 70mph on gravel are like nothing, 1ft whoops no worries at all. Only thing I even half worry about is bending the axle housing driving it like that.

I have not seen radius arm mounts ripping off the axle housing yet but I have seen plenty of egged out mounting holes on the axle mounts.

Cheers

 

[Nay]

Not everyone wants 4" lift.

I've had an 80 with 4" lift. It was fairly well sorted.
I've had a 105 with 2" lift. It went everywhere the 4" lifted 80 did, and then some.

I wouldn't do a 4" lift again

I get it - when I got here the common theme was you needed 6” of lift to run 35’s properly. We just tear these things down over time, hopefully as quickly as possible.

But nobody should ever expect to just pick a caster number on a solid axle and like the outcome. Especially if it’s on spendy bits like replacing radius arms with radius arms when you can only tweak the angles by then playing around with caster bushings. Bit of a fools game, get it dialed and don’t ever touch it again.

Enough of me here, now we await the next thread about “caster”.

 

[mudgudgeon]

Enough of me here, now we await the next thread about “caster”.

Caster thread inbound in 3 . . .

2 . . .

1 . . .


lol

 

[Broski]

Keep in mind that you are choosing caster here, but on an AWD vehicle, caster has to follow pinion angle or you are likely to get driveline vibrations. The 80 series is unique in that the front driveshaft is OEM configured in a ‘broken back’ alignment, which means the pinion is pointing upwards more than would be typical. The beauty of this is that you can convert to a double cardan driveshaft, and without doing anything else, you have to lower the pinion to create axle end u-joint alignment. Lowering the pinion increases caster, which of course is why lifting without other modifications decreases it.

If you just pick caster, and you leave the stock driveshaft configuration, you are unlikely to have good driveshaft angles in terms of avoiding vibration at higher speeds. The stock setup has people reporting various results that in the world of how u-joint angles operate makes little sense (should vibrate, reported to be fine) but leading with caster when alignment is from the pinion angle is a crap shoot.

Landtank’s plates are unique in that they don’t just drop the bracket, but install in alignment to the factory brackets while drilling new holes. They are difficult to install due to tight spaces using a right hand drill but are a great solution. I am going to drop some massive controversy on your thread and show how I am using stock radius arms with Landtank plates and a DC driveshaft with proper angles and fit 38” tires up front without trimming the fenders or restricting up travel. I have no idea what my caster numbers are because they don’t matter - if I misalign my driveshaft it vibrates, to the point that I run one OME bushing upside down to get it properly aligned. Pics tell the story.

This is my original set beside the higher caster set after grinding/prying off the welds. You are drilling through those pilot holes, not just dropping the brackets like typical caster brackets.

View attachment 3699707
You should weld them, easy enough to get back off if you ever should want to.

View attachment 3699708
This is how the radius arms align. For anybody who plans to keep radius arms and wheel hard, notice how on 5.5” of lift the arms are basically flat under the angle and will act as a slider - this is an ideal setup vs a large bend to drop a radius arm under the tierod. Which brings us to tierod clearance - I have a larger diameter heavy duty Slee tierod and everything clears to pinion and arms without any grinding of the arms. Notice the pinion angle alignment for a double cardan driveshaft (no u-joint angle at the pinion).

View attachment 3699711
View attachment 3699713

View attachment 3699714

Wow very long winded.
I run the landtank 4” lift plates and they work well and I agree that the design is preferred as it rotates the axle instead of just dropping the front.
I also run OEM Arms and I’m happy with them.
I also run some of the hardest trails out there and have posted many videos of it.
I have also run 5” of lift and IMO it down right scary and very old school.
A more common theme today is a low lift with a big tire = a lower center of gravity and a more stable vehicle.
Yes that might mean some cutting is needed but makes a safer vehicle.

 

[Broski]

This is what coil spring alignment looks like - no bow to the front coils.

View attachment 3699718
Sure looks bowed to me

Nay we seem to disagree often

Maybe we could meet somewhere halfway between us like Sand Hollow to compare rigs builds, tall lift vs low lift

I think it would be a lot of fun !

I like hard technical wheeling !

 

[stvrn6]

you can choose not to weld them but it’s not considered optional by me.

People have installed them and then driven to a shop to get the welding done. The welding is basically a small stitch at the front of each plate.

If the welding is an obstacle you can’t get around then a complete bolt on solution is your best path.

I really appreciate the honest feedback rather than trying to secure a sell, that being said i will surely be a customer soon. Your 4.0 plates would put me right around 2 correct? i will be going with those as soon as i can make sure i get them welded. my only current full bolt on option is dobinson 5 degree casters. any opinion on those? I know 5 is risking drive shaft and clearance issues. I just inspected my bushings and they are in very good condition, think the previous owner may have changed them (oem). Also my truck is on a 3 in lift, any reason my caster is so bad?

 

[landtank]

My labeling of the plates is inches of lift.
The 4.0” plates have 7 degrees of correction and the 2.5” plates has 4.3 degrees of correction

I should make that clearer on my site.

 

[stvrn6]

My labeling of the plates is inches of lift.
The 4.0” plates have 7 degrees of correction and the 2.5” plates has 4.3 degrees of correction

I should make that clearer on my site.

Got it thank you. What are the current ship times?

 

[landtank]

Typically on the first Saturday after ordered. If I’m working local it could be earlier.

 

[mudgudgeon]

Also my truck is on a 3 in lift, any reason my caster is so bad?

Every 1" of lift reduces caster angle by approx 1.7⁰.
3" lift, you lose about 5⁰ of caster.
If you have -2⁰, your original caster angles would have been right on 3⁰, which is middle of the factory spec.

 

[stvrn6]

Every 1" of lift reduces caster angle by approx 1.7⁰.
3" lift, you lose about 5⁰ of caster.
If you have -2⁰, your original caster angles would have been right on 3⁰, which is middle of the factory spec.

Thats great explanation thank you. I bought this truck with a brand new eibach lift installed. I just changed to heavier springs. Will be ordering plates soon to get me back in spec.