which caster plates for medium 3” lift DOBINSON coils C59-166 and C59-167 (1 Viewer)

[landcruiser3DP]

does anyone know whether to go with landtank 2.5 degree or dobinson 5 degree caster correction plates with these coils? i am hearing you can “get away” with 2.5 deg plates. i am also hearing that it is better to have more caster correction than less. and also that 5 degree dobinson plates require some grinding so something doesn’t interfere?

anybody been there and done that who can offer their experience with this?

THANKS

 

[landtank]

they are not 2.5 degree plates. They are designed for 2.5 inch lifts.

I offer 2.5” plates and 4” plates

 

[Heckraiser]

Have you installed the lift yet? If so, measure your hub to fender flare measurements and that will give you a clue as to which plates would be more appropriate. This will be dependent on the weight of the truck, age and type of the springs, your own caster preferences and wacky cruiser voodoo. Other people can tell you what they run, but without measurements on your truck, nothing will be 100% relevant to you.

As for "other people telling you what they run" I have landtank 4" plates and TJM progressive 50mm springs (which is supposed to be a 2" lift, but in my case turned out closer to 3") I haven't been to the alignment shop to see what my numbers are, but it steers a lot better than it used to. No vibes, and I had a DC front driveshaft before I installed them.

Many (most) lift springs out there don't actually lift by the advertised amount.

 

[landcruiser3DP]

they are not 2.5 degree plates. They are designed for 2.5 inch lifts.

I offer 2.5” plates and 4” plates

thanks man.

 

[landcruiser3DP]

Have you installed the lift yet? If so, measure your hub to fender flare measurements and that will give you a clue as to which plates would be more appropriate. This will be dependent on the weight of the truck, age and type of the springs, your own caster preferences and wacky cruiser voodoo. Other people can tell you what they run, but without measurements on your truck, nothing will be 100% relevant to you.

As for "other people telling you what they run" I have landtank 4" plates and TJM progressive 50mm springs (which is supposed to be a 2" lift, but in my case turned out closer to 3") I haven't been to the alignment shop to see what my numbers are, but it steers a lot better than it used to. No vibes, and I had a DC front driveshaft before I installed them.

Many (most) lift springs out there don't actually lift by the advertised amount.

thanks heckraiser. i appreciate that a lot. for some reason i never really wrapped my head around the idea that i should do this based upon actual real world numbers.

i guess part of it is despite reading up a ton on this i don’t remember which numbers i use to decide which degree of adjustment i should make? or it is not degree it is actually how far over stock you are?

for instance - if i have 2.5” of actual lift over stock i go with LT 2.5” plates? if i have 4” lift over stock i go with 4” LT plates?

if i have 3” actual lift over stock i ho with 4” plates because over caster adjustment is better than under?

ALSO, i think dobinson does a 5 degree caster adjustment plate. is there a way to know how a LT 4” plate compares to a 5 degree dobinson plate?

meaning i can’t get from amount of lift on the truck to degrees of adjustment without measuring but i must be able to compare the plates?

 

[landcruiser3DP]

they are not 2.5 degree plates. They are designed for 2.5 inch lifts.

I offer 2.5” plates and 4” plates

hey man,
can i please ask you this though?
if they are all 4” list plates or 2.5” lift plates can’t i do some geometry and get the actual caster adjustment in degrees if i wanted for the 2.5 or 4” plates?
i mean i know it may be an academic number in the sense degrees are meaningless (i guess unless you are looking at it at an alignment shop on a machine with a computer?!) but if i wanted to know what degree adjustment they were giving i could just find the distances and calculate it?
mind you i half understand the topic but that doesn’t stop me from trying!

 

[Heckraiser]

I have read some threads where people more into geometry than I am actually spell out how much correction (in degrees) is needed for lift (in inches). It is progressive, meaning the first inch of lift will not require as much correction as the 4th inch of lift. In fact, I think Mister Landtank himself may have posted something along those lines at some point. I hate to say "search" but it's out there somewhere and I don't feel like digging for it at the moment

 

[landcruiser3DP]

I have read some threads where people more into geometry than I am actually spell out how much correction (in degrees) is needed for lift (in inches). It is progressive, meaning the first inch of lift will not require as much correction as the 4th inch of lift. In fact, I think Mister Landtank himself may have posted something along those lines at some point. I hate to say "search" but it's out there somewhere and I don't feel like digging for it at the moment

THANKS man.

i have those threads here and read through them all but i was trying to figure out the install steps to figure out what i needed and what i was needing to do so i was not paying so much attention to the geometry stuff. i do know there is some killer geometry in dave's delta systems threads on the radius arms and that bracket he makes but i just was not crazy about trying to find it myself again i must admit.

i'm pretty good with constructional stuff and details but i have to admit some of this gets me a bit confused. which is why i try to ask.

for instance the dobinson plates are 5 degree plates. the LT plates are 2.5" and 4" and slee plates are 4" and whatever else they sell. so it seemed like there should be some relation between inches on the plates and the actual degrees at least to me. also, (again despite doing a lot of reading) i am not really totally sure when you would get the 2.5" and when you would get the 4" plates if you were putting on a 3" lift.

i also have to admit to even now not totally understanding how that adjustment is happening which i always find helpful before cutting into s***. i guess after getting your and others' help i am /lowering/ the front - well actually i am not really sure how those plates work geometrically. they are lifting the rear single set of bushings at the frame is that what they are doing? or other way around?

 

[Irish Reiver]

A 3" lift is the twilight zone for cruisers. You lift this much and without a doubt you need to correct caster....but by how much? Too little and the steering will feel very squirrely on the highway, too much and the pinion angles on the front diff will be misaligned and risk causing vibrations. On top of that interference with the steering and control arms is very likely.

So what is the sweet spot? I have a true 3" lift. I tried the 5° toughdog plates and had the vibes and interference. I swapped to landtanks 2.5" plates - significantly reduced vibes, zero interference- still feels a little loose on the highway. Compromise is the name of the game. I would love better steering control but don't want vibes.

Go with the landtank 2.5" lift plates and keep your fingers and toes crossed.

 

[landtank]

There is a lot that goes into predicting what amount of caster you need.
The amount of extra weight added to the truck will influence the trucks ride height which influences the caster needed to regain caster to factory specs.
Another is that if you measure your caster and then adjust the caster accordingly you will likely fall short because as you rotate the axle during the correction you better align the spring perches making the springs mire effective at supporting the weight and giving a lower caster reading.
I ask people to measure the distance from the hub center to the underside of the fender after installing the springs and subtract 20.5”. This will give me an assumed lift height that I ca use to predict the out come from using my plates.
All the variables from lifting the truck and using my plates are baked into this equation. It’s not intended as a tool for predict outcomes or solutions for other vendors solutions.

 

[retrofive]

FWIW I ran a OME J lift (~3") and 1.5" coil spacers in front. I used MetalTech's plates and their spacers. IIRC chatting with Mark, he designed the plates around the J lift. Anywho that combination netted me 2* of caster.

 

[landcruiser3DP]

A 3" lift is the twilight zone for cruisers. You lift this much and without a doubt you need to correct caster....but by how much? Too little and the steering will feel very squirrely on the highway, too much and the pinion angles on the front diff will be misaligned and risk causing vibrations. On top of that interference with the steering and control arms is very likely.

So what is the sweet spot? I have a true 3" lift. I tried the 5° toughdog plates and had the vibes and interference. I swapped to landtanks 2.5" plates - significantly reduced vibes, zero interference- still feels a little loose on the highway. Compromise is the name of the game. I would love better steering control but don't want vibes.

Go with the landtank 2.5" lift plates and keep your fingers and toes crossed.

thanks man. super helpful info here as usual. appreciate it.

 

[landcruiser3DP]

There is a lot that goes into predicting what amount of caster you need.
The amount of extra weight added to the truck will influence the trucks ride height which influences the caster needed to regain caster to factory specs.
Another is that if you measure your caster and then adjust the caster accordingly you will likely fall short because as you rotate the axle during the correction you better align the spring perches making the springs mire effective at supporting the weight and giving a lower caster reading.
I ask people to measure the distance from the hub center to the underside of the fender after installing the springs and subtract 20.5”. This will give me an assumed lift height that I ca use to predict the out come from using my plates.
All the variables from lifting the truck and using my plates are baked into this equation. It’s not intended as a tool for predict outcomes or solutions for other vendors solutions.

thanks a lot rick.

so i should put the 3” lift on, get it loaded “normally” and see where i end up after subtracting out 20.5”? then post back?

or if i am at 2.5“ after doing the calculation i go with the 2.5 plates and if i am at 2.75 or more (or 3 or 3.25 or whatever or more?) go with the 4”? i mean can i make that call now just for my own convenience sake?

also can anyone give me a heads up on welding please? can i install 2.5“ LT or 4” LT plates and drive to a welder to put it on a lift and stitch weld it? or is this a really bad idea? or actually otramm seems to indicate he would really like to see them welded on when it is on the ground i guess?

i mean i don’t really want to pull it apart any more times that i have to so i am thinking either i will have both sets on hand and install one of the set of plates while i am doing the lift basically. and then pull them and run it over to have them put back in and welded up. or i will install whichever set makes sense after measuring and find someone to run over and crawl under and stitch it.

 

[landcruiser3DP]

FWIW I ran a OME J lift (~3") and 1.5" coil spacers in front. I used MetalTech's plates and their spacers. IIRC chatting with Mark, he designed the plates around the J lift. Anywho that combination netted me 2* of caster.

i guess it is my thread so i can ask whatever i want...

retrofive! do you mind reminding me how the caster is calculated? can i literally run a couple of string and ballpark the caster - if i wanted to - with a protractor i suppose?

or do i need to get the value by getting it on a adjustment machine or how does that work exactly please?

both?

 

[retrofive]

Install the lift (no need to mess with the arms doing that). Get your caster measured at alignment shop. Report back with that number and that will tell you amount correction you need in the plates. Stock is between 2*-4*

 

[retrofive]

i guess it is my thread so i can ask whatever i want...

retrofive! do you mind reminding me how the caster is calculated? can i literally run a couple of string and ballpark the caster - if i wanted to - with a protractor i suppose?

or do i need to get the value by getting it on a adjustment machine or how does that work exactly please?

both?

I had a lifetime alignment from Firestone, so honestly just ran it down there to get the camber/toe/caster (not that you need all those). There is a some DIY measuring I believe around here. But liked the shops laser and sh!t method

 

[landcruiser3DP]

I had a lifetime alignment from Firestone, so honestly just ran it down there to get the camber/toe/caster (not that you need all those). There is a some DIY measuring I believe around here. But liked the shops laser and sh!t method

thanks man. yeah i guess if there is a thread around here i would print it out. maybe it is in one of the delta threads i had printed out here at one point.

i guess i probably would take a line level and/or a laser level and “snap some measurements” myself if i knew how to do it. it would be an interesting way to wrap you head around it i think...

 

[retrofive]

thanks man. yeah i guess if there is a thread around here i would print it out. maybe it is in one of the delta threads i had printed out here at one point.

i guess i probably would take a line level and/or a laser level and “snap some measurements” myself if i knew how to do it. it would be an interesting way to wrap you head around it i think...

Short visual.

 

[retrofive]

How to measure castor?

I've don't recall seeing THIS aspect of castor/alignment covered before so here we go. When my OME was installed with CC the alignment report said I was at 3 deg. pos. It drove fine and still does. I had the alignment checked because of crazy tire wear recently and everything was fine, except...

forum.ih8mud.com

Where to measure caster with angle finder

I have truly searched, but the keywords I have used versus the number of hits is tiresome. With an angle finder, is there a quick location to get a preliminary caster degree measurement? '93 FZJ80 Thanks, Ty

forum.ih8mud.com

 

[landcruiser3DP]

Short visual.

View attachment 2367201

thanks man. that’s great. that’s showing positive caster i guess. and negative caster is what you get when you lift i guess...