caster plates on a 3" lift

[jsttry]

I've got an 80 series with 3" lift that currently has -2 and -2.37 caster.

General theory would expect that a 5 deg caster plate would bring them back closer to factory tolerance of +2.45.

Talking to Wizard Performance I was told the 5deg plates wouldn't fit on a 3" lift as they'd make the tie rod hit on the radius arms or tail shaft.

Does anyone else have experience fitting caster plates to a 3" lift?

Other option is 3deg bushes but they are harder to install and being nothelane won't flex as well. They'll also only bring the caster back to +1 and +0.63.

[dow50r]

I ran a set on a 3 inch lift, nothing hits, but the spring coil rub up front on the internal bump stop both sides....makes the cruiser very heavy steering and great at return to centre.
You obviously have a bent diff to get those different angles, does the passenger side top swivel have a threaded bolt in the middle (caster adjuster)
Andrew

[jsttry]

nope, is a 91 model. Didn't know any 80 series cruisers had caster adjustment. Would be nice, could mean you'd be able to dial it in/out a fraction.

How does caster affect your bump stops? You mean they were hitting at the front from the axle being rotated or they were hitting on the outsides due to bent mounts?

Never jumped it and previous 2 owners were pretty responsible, but who knows, could always have some bends in it.

[dow50r]

Just ment that the difference in side to side caster measurement is a slight bend in the housing...might be bigger and a cast-o-lign offset bush has been installed, thats why i asked about the thread....its one of them....which gets it all back to close on whats required.
hen you put plates on the diff is rotated back and the springs therefore come close to the bump stop that is in side them...no biggy, when you hit a bump and you hear a twang, thats what it is...i just got a grinder to the front face and cleaned it up a bit, no more noises.
Andrew

[jsttry]

These are the two areas I think are of concern



Particularly if the plates rotate the diff down then it will be closer to the tie rod.

[dow50r]

Question. What changes with the orientation of these points with lift?
The 5 deg plates do make things tight, but size of lift doesnt come into play at all...whether you have 6 inch or 3 the steering arm will sit in thesame position on both.
The plates make the diff brackets stronger and the rubber in the arms allows more flex, i would do this over offset bushes
Andrew

[SuperiorEngineering]

[quote="jsttry"]

Talking to Wizard Performance I was told the 5deg plates wouldn't fit on a 3" lift as they'd make the tie rod hit on the radius arms or tail shaft.

What the Fu**

I would love to be told how lift makes any difference to how close the tie rod will be to the radius arm.?????????????????
The different caster correction eg, 5 degree will put the tie rod closer to the radius arm than 3 degree bushes but that has NO bearing on what the coils/ lift is. All this determines is what caster correction to use.

I do not recommend 5 degree plates with a tru 3 inch lift it will encounter headshake as soon as you get any sag in the springs if not straight away, less caster is more usable in vehicle because it will be a bit wandery and not go into a dangerous headshake

[jsttry]

Thanks mate.

The reason I am thinking 5deg plates is because currently with no caster correction it is -2 and -2.37. Adding 5deg takes it to +3 and +2.63.

3deg bushes only takes it to +1 and +0.63. And there is the issue of reduced flex.

Any idea how much the plates change the distance from the arms to the tie rod?

Spings have been in there a couple of years so have already settled. It has coil spacers in the front to level it out. Could always measure to know exactly what size lift it has resulted in but as you said, makes no difference, end result is the caster is still currently a fair way out of whack and it wanders like buggery.

[SuperiorEngineering]

Thanks mate.

The reason I am thinking 5deg plates is because currently with no caster correction it is -2 and -2.37. Adding 5deg takes it to +3 and +2.63.

3deg bushes only takes it to +1 and +0.63. And there is the issue of reduced flex.

Any idea how much the plates change the distance from the arms to the tie rod?

Spings have been in there a couple of years so have already settled. It has coil spacers in the front to level it out. Could always measure to know exactly what size lift it has resulted in but as you said, makes no difference, end result is the caster is still currently a fair way out of whack and it wanders like buggery.

From the toyota's we have fitted plates too, there seems to be a slight variation in the casting of the radius arms, on some with a 5 degree plate the tie rod makes contact with the radius arm and others clear by a small amount, this is why a 7 degree plate was impossible for anyone to design/ fit , so the drop radius arm came about.
Caster plates on toyotas are bolt on so its not a big thing to try them but i will be very supprised if it does not shake when hitting a pot hole, for me i would go bushes, the toyotas are pretty good for flex in the front for a 3 link. ( Pretty scary having a headshake at 100k with oncoming traffic )

[jsttry]

what causes the shake, too much caster?

[gtir300]

I went through exactly the same issue with a 3" lift in my 80.

Had an alignment that said caster was -2, so bought 5deg plates and eventually got them in. Tie rod ran very close to the radius arms, so much that I got a vibration. Originally thought it was the front diff that was broken, looked at the tie rod and it had approx 1mm clearance (if that) so when on the road it vibrated.

I took off the caster plates and they now live in the shed.

I had 2deg bushes put in and it drove like a dream. 3deg bushes may have been better.

I would recommend getting another alignment done by someone else, to check those caster values.

Have since sold the 3" lift (wish I never had) and fitted 4-5" springs so caster is now out and I need to fix it.

Just waiting on some bits from Superior through a 4wd shop to get new shockies fitted. Once thats in I will then get an alignment done to determine what drop arms I actually need - again I hope to get Superior ones if they are available.

[mellows40]

G`day guys I`m in the process of fitting superior drop shackles all round on my 40 series and oh boy does my old girl wander all over the road...

yeah it`s 30 somthin years old and a shorty what do I expect...

My question is this.. where do go to find out how far the caster angle is out and how many degrees of caster wedge will be needed to firm up the steering?

i have recently changed all tie rod ends, shocks, leaf springs, c/v`s swivel seals, free wheeling hubs,disc brake conversions from drum`s, And made a heavy duty bash protection plate to protect the gearbox and t/case..... And am looking to toughen it up a fair bit

cheers Mellows 40

[rockcrawler31]

what causes the shake, too much caster?

I'd like to know this as well

I've got custom arms in a truck with a custom coil conversion. It's all been good up to now but i've noticed that very recently it's started getting uncontrollable shakes and death wobbles when i hit a bump. I tried going back to a two inch lift (started when i put in a set of 5 inch coils) because i hadn't had any drama's with them, and it did it once with those in as well.

the arms are made so that at a 2 inch lift it has factory castor and at 5 inch it should have the same castor as a factory truck with a 3 inch lift. Although i havn't taken it to a alignment to have that checked.

i always thought that not enough castor gave you the wobbles as the return to centre effect of excessive/factory castor stopped the wheels from wanting to turn. Maybe i'm wrong.

some one did mention to me that because i'm not running a steering damper at the moment that that is the cause. But i always thought that a damper just hid problems and most factory dampers are next to useless anyway. Again, i may well be wrong

[80's_delirious]

what causes the shake, too much caster?

I dont think so. I run 4deg caster on 80series with 4'lift and 35" tyress with no problems. Toyota specify brtween 2 and 4 degrees caster for 80series.

check Panhard bushes as the most llikely problem, then check wheel bearings, king pin bearings, tie rod ends and radius arm bushes for play. it doesnt take much play to make a big difference with lift and big tyres.