.2WD Ball Joint Spacer and Brace Installed - Brace can also be installed w/o spacer
These spacers are 1.5"/38mm tall and provide about that much front
suspension lift over stock suspension settings as well as that much
more overall front suspension travel. Actual front lift height will
depend upon the vehicle's weight distribution and current torsion bar
condition and adjustment which may be 1.5" more or less than the
spacer height. Whether or not you prefer enhanced compression travel
for high speed trips through desert washes or a balance between
compression and extension travel more suited for rocky trails, these
spacers will increase your functionality and ability to custom tailor
your suspension characteristics while increasing clearance between the
fenders and front wheels. If 1.5" is too tall for your needs,
shorter spacers are available on special order. An installed 4WD spacer
is shown on the far right hand image, above.
Also available for the 2WD Toyota pickups as shown in the lower right
hand image above. In the 2WD suspension, the torsion bar is mounted to
the lower control arm, not the upper control arm like in the 4WD
suspension. So the 2WD spacers will typically require some torsion bar
adjustment to attain a similar lift to the 4WD spacers. But the
advantage that the spacers provide over just
cranking up the torsion bars is that they provide the
additional bump stop clearance so even with the torsion bars set
higher, you still get full suspension travel.
When combined with a mild rear suspension lift, either a lift shackle or block
or coil spring spacer, and
possibly a mild body lift, it is
easy and relatively inexpensive to fit 33" tires under an IFS
truck. While a full 4" - 6" IFS spacer lift can be installed
and will work fine for 33" tires, for less than 1/2 the price and
less than half the time and effort, you can install a milder lift that
will actually work better than the taller lift. In fitting with the
4Crawler Offroad motto of "lift as much as you need, but as
little as possible", why use a 4" - 6" lift when
1.5"-2.5" will work just as well, if not better? With less
lift, your center of gravity will be lower, drive line angles will be
less, brake lines will usually not need to be extended, and overall
there will be less stress on the components.
So apparently the saying "Imitation is the sincerest form of
flattery" applies here as well! In fact we have noticed
that some of the online auction sellers of Toyota Ball Joint Spacer
kits are selling almost exact duplicates of our product and we
even know now that they ordered one of our kits and copied it. We say
"almost exact duplicates" because they missed one
minor, but crucial aspect of the our design in their copy. We mention
that difference in the installation instructions, but in order to not
make it easy for the competition to find that aspect of the design,
we'll not describe it here. But it sure makes it easy to offer low
prices when your R&D budget is negligible - as in you steal all
your new designs. Oh, and to top it off, they even our plagiarized our
installation instructions, nearly verbatim, even down to the
punctuation. If these guys were writing these instructions for a
college paper, their professor would likely fail them for cheating. Not
only that, but as we describe below, these vendors
are advertising 2.5" or 3" "lift" spacers, and yet,
when you measure their spacers, they are only 1.5" tall. As Clara Peller was so
fond of saying, Where's the Beef?" And not only are the spacers
not the full advertised height, but we have found that the cast
aluminum spacers are also lighter than the billet aluminum used in our
spacers. Our CNC machined billet
aluminum spacers weigh in at 16 oz. (454 g.) each and a
popular cast aluminum spacer off of eBay weighs about 14.1 oz. (400 g).
So either those spacers are made of some super light alloy or they have
voids in them. Since 6061 aluminum alloy is the most common and lowest
cost aluminum alloy and to get lighter you need to add something like
magnesium which is twice the cost of aluminum, it is unlikely that
these low cost cast spacers are made of some high-tech super light
alloy, so in all likelihood they are a porous casting, since air costs
nothing and adds no weight. Judging
by the rough surface finish of those cast spacers, it is not hard
to believe they are full of voids, in the linked image, the cast spacer
is on the left next to our CNC billet spacer on the right. Note that
our spacers are now put through a tumbled finish to even out the
appeareace of the non-machined mill finish top and bottom compared to
the fully machined inner and outer faces. But if you look closely, you
can still see the fine machining marks. Also, we have heard reports of
purchasers of such spacers also finding issues with substandard grade
hardware. In fact, we have supplied our replacement
hardware for many customers who have experienced failure with these
cast spacer kits.
In Other Words "Which Ball Joint Spacer do I need for my truck?"
In short, you'll want to look at the type of front suspension/ball
joint is used on your vehicle (see the above two photos for the two
types of front torsion bar suspensions that Toyota used). If you have a
4WD truck, the answer is simple, you need the 4WD
spacer.
However, if you have a 2WD truck, then the answer is a little more
involved. The 4WD spacers also work with 2WD trucks with "pre-runner"
type suspensions. A pre-runner suspension is essentially
the same as a 4WD suspension with the front drive train (differential
and CV axles/half shafts) removed. This would include of the 2WD
4Runner and some T-100 models. Typically also fit the 1996 and later
Toyota Hilux 4WD pickup models (non-US) that use the same torsion bar
front suspension with matching ball joints (check dimensions below to
verify proper bolt hole spacing).
The 2WD spacers are available for the earlier 2WD
pickups and some 2WD T-100s (i.e. pre-Tacoma).
Which type to order? Compare the photos above with your truck's upper
ball joint to find which type matches the shape of your vehicle's upper
ball joint.
On the "2WD" ball joints, you'll note the inner pair of bolts
holding the upper ball joint in place are wider apart (~3-1/2" -
90mm) than the outer pair of bolts (~2-7/8" - 75mm).
The spacers are 4-5/16" long (front-back dimension as installed)
and 1=15/16" wide (left-right dimension as installed).
On the 2WD ball joints, the ball joint itself essentially hangs off the
end of the upper control arm (UCA).
On the "4WD" ball joints, the inner pair of bolts is closer
together (~2-3/8" - 60mm) than the outer pair of bolts
(~3-1/4" - 82mm).
The spacers are 4-1/32" long (front-back dimension as installed)
and 3-5/32" wide (left-right dimension as installed).
The 4WD ball joint sits inside the end of the UCA.
And the ball joint spacers of of course not applicable if your vehicle
has had a "solid axle swap" (or SAS) where the front IFS
suspension has been removed and a leaf or coil sprung solid front axle
has been added on.
4Crawler Offroad assumes the buyer to be the final
manufacturer of his or her vehicle. Use this product at your own risk.
4Crawler Offroad assumes no responsibility for any damages of any
conceivable sort to anything caused or not caused by this product.
The user is responsible for ensuring shock fitment.
Hardware consists of M8-1.25 class 12.9 socket head cap screws, class
10 flanged nylock nuts, and flat washers.
Use of Loctite on hardware is not necessary when using a nylock jam nut
but can be used if desired.
Either stock extension bump-stops or shimmed bump-stops
(low profile only) are required with this spacers in order control max
droop angles. Failure to do so could result in damage to CV joints or
other components.
Our default shipping method is USPS mail and default payment option is Paypal. If you wish to use a different shipping or payment method, please contact us prior to ordering. Let us
know the item(s) you want, where and how you'll want them shipped to and we'll get back to you with a shipping quote and purchase information:
NOTE:
Beginning 01.Jan.2021, we'll no longer be able to accept orders shipping to the UK via our on-line order system due to the VAT
requirements. Click here for alternate ordering options.
Now available for the 2WD applications are both the ball joint spacers
as well as a heavy duty brace for the upper A-arm. Larger tires and
off-road use puts stress on the upper control arms. This can cause the
outer end of the control arms to fatigue. These braces strengthen that
area eliminating the problem. They are made from 1/4" (6mm) thick
steel, available in bare steel, etching primer or cold galvanize primer finish. These are
recommended for any 2wd truck that sees off-road use or will be running
wheels/tires significantly larger than stock. The A-arm brace can be
used with the stock A-arms or with the addition of the ball joint
spacers. For stock arms, check to see you have enough exposed thread on
the ball joint studs to fit the brace on top. If your studs are not
long enough, you can use 8mm bolts to replace the studs. If you can't
get bolts, you can order stock length replacement
hardware.
Note: The upper control arm braces add no lift, they are for reinforcing the upper control arm.
They can be used with or without the 2WD ball joint spacers.
1 brace shown, kit includes 1 pair, i.e. 1 brace for each side.
US Priority
US Express
Canada Priority
Int'l Priority
Notes:
Order with the above "Buy Now" buttons using major
credit/debit card, bank eCheck or Paypal account.
eCheck orders are subject to a 3-4 day hold while the eCheck clears the
bank
Please be sure todouble check your shipping
addressbefore submitting your order:
In the 4WD spacers, heights of 3/4" or less may lessen or
eliminate the amount of metal trimming of the upper control arm needed
to install the spacers.
For the custom height spacers (i.e for heights less than 1.5"),
cost is $99.00/pr. (4WD or 2WD) to cover the custom machining and
hardware. Allow 1-2 weeks for custom machining. Spacers will include
longer hardware (h/w) for the height of the spacer, i.e.
the Normal h/w option (i.e. height of spacer equals
length of hardware).
If requested, we can supply extra long hardware to accommodate stacking
these new spacers on to of an existing ball joint spacer. So for
example, if you already have 1.5" ball joint spacers and wish to
add another 0.5" spacer on top of that, order that height spacer
and select the Extra Long h/w + 1.50in. option when
ordering. We can't guarantee these stacked spacers will work on any
given vehicle, as noted here, but you are welcome
to try. We have had some customers who have had good success with this. Note
that this Extra Long hardware option is only available for 0.5"
and 0.75" tall spacers.
The custom height spacer height will be within approx. 1/16" of
the specified height.
Possibly, yes, possibly no. It all comes down to the shocks that are on
the vehicle now and how they fit with the existing suspension setup and
how much lift you are going for. If the current shocks are on the verge
of being too short to begin with, then likely any amount of lift will
push them beyond their capability. If, on the other hand, the shocks
are a little too long for the current setup, then they may have enough
extra length to handle a modest lift.
The best option is to measure the compressed and extended shock lengths
needed for the spacers once they are installed. Then order a shock that
meets those needs.Here is a table of
some common longer shocks that may be suitable. And here is a
link to a good article on how to determine
proper shock absorber lengths on a given vehicle. Typically,
you would be looking for a front shock with a 10"-10.5"
compressed length and a 15" extended length. Then use those
dimensions to order shocks from a company that lists shocks by length, for example Rancho is one such company.
Or, many shock companies list shocks by "lift", so you could
order a shock for the approximate amount of lift you have, so perhaps a
0"-2" lift shock, for example.
Now, on a vehicle that is primarily driven on the street (i.e. not used
off-road that much), then a shock that is a little too short may not be
a serious issue. Since you are not routinely lifting tires off the
ground on pavement, it is unlikely that you'll be extending the
suspension to full droop and therefore not maxing out the
shock travel. Also, if the shock is close to fitting, you can see the installation instructions
for tips on shimming the front shocks for a little extra extended
length.
You can also measure the shock length you currently have prior to
ordering/installing the spacers. To do so, simply lift the front tires
off the ground to let the front suspension drop down all the way (i.e.
"full droop"). THen unbolt one shock on one side of the truck
and see if it is limiting the current down travel at all (if so,, you
already need longer shocks - even before installing any spacers). And
if there is any extra shock down travel left, measure how much (i.e.
how much farther does the shock extend when disconnected). If you have
about 3/4" - 1" of additional travel that may be sufficient
with the spacers, since the shocks attach approx. half way out on the
suspension control arms and so will see about one half the added ride
height.
Realize that the ball joint spacers (and any subsequent torsion bar
adjustment) will only affect the front end ride height (i.e. lift) and
not lift the entire vehicle.
In answer to the above question, yes, no problem doing that within
reason. Some folks install the spacers and then take all the pre-load
tension off the the torsion bars, netting almost no lift but increase
suspension travel. Others crank the tension on the bars up for
additional lift.
And on a related question as to how much lift will you see on your
truck? It is hard to give an exact answer as each vehicle is different.
Different engines, bumpers, winches, up front, torsion bars of
differing degrees of wear and tear, different sized torsion bars, etc.
So the lift you get is whatever you get when you install the spacers.
One would assume that a 1.5" tall spacer should net about
1.5" of lift, but might be a little less since you are putting a
little more load on the front end with the lift.
Try before you buy:
Want to get an idea how much lift you'll see from a particular height
spacer? Easy enougn to do if you have some scrap wood available. Simply
make a pair of wooden padsto drive your front tires up onto. You could
use 1/2" or 3/4" plywood for the shorter custom height
spacers or some 2x lumber on it's side for the 1-1/2" spacerrs.
Just make sure to use enough wood to cover the contact patch of the
tire. Lay that in front of the tires and drive up on it. Then bounce
the front suspension a few times by pushing down on the front bumper to
settle it in. Now meaure the height difference before and after driving
up on the wood spacers. This should give you a fairly good
approximation of the lift you can expect on your truck with the ball
joint spacers.
An interesting thing to note is that some vendors are
advertising ball joint spacers as a 2" (or even 2.5" or
3") lift option. While that much lift is possible, realize that
the spacer itself is likely to be only 1.5" tall. Any additional
lift is accomplished via the torsion bars. 4Crawler Offroad has chosen
to advertise the spacer by it's inherent height rather than some
arbitrary height.
So how much overall lift can one expect?
Well, it all depends on you and how far you want to adjust your torsion
bars and how you feel about the ride that results from that adjustment.
Generally, with the IFS setup, the higher you crank the torsion bars,
the harsher the ride gets. This is due to the increased angle of the
control arms as well as the lesser amount of down travel in the
suspension. So 3" total lift is probably the physical limit of the
IFS components and you'll have 0 down travel as the a-arms will be
jammed against the bump stops. 2.5" total lift (as some of the
eBay spacer vendors advertise) is likely the highest useable height,
but likely a pretty harsh ride to most folks. 2" total lift is
likely somewhat decent and 1.5" and lower would give you stock
ride and the most suspension travel. And realize that the higher you
raise the front end, the more you'll be pushing the limits of the
steering geometry adjustments (camber, caster and toe-in). So the
higher you lift the front end, the more likely you are to run out of
adjustment on the cams that set the front caster and camber angles. So
if you find you can't get the front alignment right at a given lift
height, lower the front height until it will align. This is especially
true if there is some minor front end damage. For example, we had one
customer report not being able to set his front end alignment after
installing the ball joint spacers. Come to find out, he could not
adjust it properly before the ball joint spacers were installed. Go
figure!
And on a side note, why are ball joint spacers taller than
1.5" not made??
Because putting a spacer that tall would cause the angle on the front
CV joints to be very steep at full suspension droop. Even at 1.5",
you need to be sure and run stock height bump stops to limit the
suspension's down travel to a safe level. It was found that most IFS
front ends would start to bind with a 2" spacer installed, so the
maximum height was backed off to a more reliable 1.5" height. Even
so, owing to CV joint manufacturing variations, there are cases of CV
joints that just show signs of binding at full droop with the 1.5"
spacers. In this case, an easy fix is to install a front differential drop kit to lower the
front diff. and lower the angle on the front CV joints. So what would
be the point of making a 2" ball joint spacer that would likely
cause almost every set of CV joints to bind up at full droop? Also, tie
rod end angles get steeper as the spacer height is increased as well as
hitting the limits of adjustment on the front suspension alignment cams
(this applies to 2WD and 4WD applications). So, 1.5" is the
tallest practical spacer height that works well for most vehicles. And
if you do want 2" of lift, there is no issue with turning up the
torsion bars that additional 0.5" if your front axles will
tolerate it. And that small a torsion bar lift will likely have no
noticeable affect on ride, at least when compared to doing the full
2" lift with torsion bars alone. And adjusting the torsion bars is
really not that difficult, just takes a couple of wrenches and you can set your front
ride height as you please.
But if you just have to have a 2" spacer, we can set you up with
an additional 0.5" spacer to add on top of the 1.5" spacer
with some extra long bolts. Just order a 0.5" custom height spacer and
the 1.5" spacer and we'll set that up for you. And we can supply
you with the mounting hardware to revert to the 1.5" spacer so in
case you find that the taller setup is too much for your front end, you
can revert to the lower height. If you are worried about the two
spacers slipping past each other, simply apply a coat of epoxy to the
mating surfaces prior to installation and then once clamped down with
the bolts, the epoxy will harden and the two spacers will become one.
And interestingly, some other ball joint spacers vendors only supply
stackable spacers in 1/2" thickness.
Yes, larger torsion bars work fine with the ball joint spacers. Some
folks choose to run the spacers to allow the stiffer torsion bars to be
backed off for a softer ride while retaining the same lift. Or you can
adjust the bars to get increased lift.
Yes, the ball joint spacers work fine with the typical 4" -
6" IFS lift kits. Some folks choose to run the spacers to allow
the torsion bars to be backed off for a softer ride while retaining the
same lift. Or you can adjust the bars to get increased lift.
Yes, some long travel IFS lifts work fine with the ball joint spacers,
at least those kits that use ball joints that retain the stock mounting
holes. There are long travel kits that replace the upper ball joint
with a higher travel uniball joint and that does not use the stock ball
joint mounting holes and those of course will not work with the ball
joint spacers. Some folks choose to run the spacers to allow the
torsion bars to be backed off for a softer ride while retaining the
same lift. Or you can adjust the bars to get increased lift. One
notable exception is the Blazeland LT kit in that it basically
incorporates something like a ball joint spacer on the end of the upper
control arm and trying to add another ball joint spacer under that is
likely to push the front end parts beyond their limits.
All shipping is via US Mail. Domestic
Express Mail is typically 1-2 days delivery time, domestic Priority
Mail is typically 2-3 days delivery time. For international shipments,
Domestic shipments include US Mail tracking and insurance. In case of
loss or damage, 4Crawler Offroad will be happy to file an insurance
claim with USPS on your behalf. Once the claim is paid, a replacement
set of spacers will be shipped at no cost. Or you can order a
replacement set and upon claim payment, the original purchase price
(less shipping) will be refunded.
For international shipments,
Priority Mail International is used where possible, it takes 6-10 days
typically. A delivery confirmation (tracking) number will be e-mailed
upon shipment, but this information is not guaranteed to be updated on international shipments.
Also, no shipping insurance is offered with this service. If more
detailed tracking information or insurance is required, international
Express Mail shipping (~5 day delivery time) is available at an
additional cost, contact
4Crawler Offroad for more information
For the rear coil sprung 4Runners, a 2" coil spring spacer makes
a good way to level the rear end. Using a slightly taller spacer in
back helps make up for the common rear end sag in the 2nd generation
4Runners.
While both techniques can provide the same amount of lift, the ball
joint spacers will afford a softer ride and more suspension flex
compared to the cranked torsion bars for a given ride height. Why? The
more the torsion bars are cranked, the tighter they get and the less
likely they are to allow for full travel. With the spacers, you get the
added ride height of the spacers without the need to tighten up the
torsion bars as much, so the suspension can flex more. As far as the
suspension and steering components go, there is no difference in stress
or wear and tear on them at a given ride height whether that be from
cranking up the torsion bars or running the spacers. So running the
spacers gives the advantage of increased suspension travel over simply
cranking up the torsion bars. A side effect of the spacers is that they
separate the upper and lower control arms by the height of the spacer.
This in turn means that the distance the upper and lower control arms
can move before hitting the bump stops is increased with the spacers.
So if you want to "crank up" the torsion bars on top of just
installing the spacers, you'll at least be gaining that potential
increase in control arm movement. For example, without spacers, the
upper limit of lift height is when you crank up the torsion bar until
the down travel bump stop contacts the upper control arm. At this
point, you have no more down travel and only have up travel in the
suspension, which can lead to a very harsh ride. If you were to install
a ball joint spacer at that point and lower the ride height back down
to the previous height, you would still have some down travel left in
the suspension.
Of course the advantage of the cranked torsion bars is that it can be
done at no additional cost.
And on a related question, how about simply installing larger torsion
bars for added lift? While a larger diameter torsion bar will provide
lift in that a torsion bar (or any spring) will have an effective
spring rate measured in so many pounds of force per inch of wheel
travel. So assuming you start at the upper bump stops, a stiffer
torsion bar will settle less distance for the same amount of weight as
a softer torsion bar. But just like the cranked up torsion bar scenario
above, you may find that a stiffer torsion bar will not allow for full
compression of the suspension assuming a nearly stock weight vehicle.
Sure, if you have installed a big heavy V8 engine or have a massive
front bumper and winch or if you do a lot of high speed pre-running and
need the added stiffness to prevent bottoming out, you might be able to
get that stiffer bar to flex for you. And it is important to understand
how torsion bar stiffness changes with diameter and how that relates to
the vehicle weight. Torsion bar stiffness increases proportional to the
4th power of the diameter:
So while a 25mm bar does not sound all that much bigger than a stock
22mm bar, it is in fact 66% stiffer. And if you figure you have perhaps
2000 lbs. of vehicle on the front wheels, increasing the torsion bar
stiffness 66% would imply adding something like 1300 lbs. of front
weight to get the same sort of torsion bar flex. So that 100 lb. bumper
and 80 lb. winch is small potatoes as far as a stiffer torsion bar
goes. For sure, if your old torsion bars are maxed out on
adjustment and you are still bottoming out, by all means consider
replacing them, but don't go overboard. Something like stock diameter
or maybe 1mm larger should get you back to the stock setup without
making the ride too stiff.
No, manual hubs are not required to use ball joint spacers. You may
find that manual locking hubs will help to reduce wear and tear on the
CV joints and boots if you have the Automatic Differential Disconnect
(ADD) front axle. Why? With ADD, you have drive flanges on the front
axle half shafts meaning the axles, CV joints and CV boots are spinning
100% of the time. With ADD, when you engage 4WD, an actuator in the
front differential locks the the driver's side axle to the differential
to make the front axle operational. With manual hubs, you can unlock
the hubs when you only need 2WD operation and thus those CV joints and
boots will not be spinning.
But with ADD, you do not have to give up the shift on the fly 4WD to
have manual hubs? How is that? Simple, with manual hubs, if you lock
them, you have exactly the same setup as the stock ADD drive flange,
you can shift in and out of 4WD any time you wish. And no need for an
expensive manual hub conversion kit like some vendors are offering.
Just grab a set of manual locking hubs from an '86-'95 Toyota pickup or
4Runner and a few parts from the dealer and you are ready to swap.
Yes, we can supply new mounting hardware for the spacers. Perfect
solution if you have lost your original hardware or if you want to
upgrade the unknown grade hardware often supplied with the low cost
eBay ball joint spacers. This is the same Grade 12.9 metric socket head
cap screws and Class 10 flanged lock nuts that comes with the
spacers originally. Cost for a full set of 8 bolts, washers and
nuts is US$20.00. Individual pieces are also available in case you
misplaced a bolt or two, those run US$3.00 per bolt/washer/nut
combination. If running the 2WD spacers with the upper control arm braces, specify the 2WD option for slightly longer bolts needed for the braces.
That is up to you and how you plan to use your truck. Since it has
probably been driving fine since it was new and if you plan to continue
driving it in the same manner, then you probably are fine just adding
the spacers. The 2WD ball joint spacers will not radically change the
forces and loading on the UCA. However, if you plan to drive the truck
off-road more with the added lift and especially if you plan to do
activities like "pre-running" or high speed off-road driving
with jumps and bumps, then you will be pushing the stock suspension
components pretty hard. In that sort of use, you can over stress the
ball joint mounting points on the UCA and that metal can fatigue and
ultimately crack under heavy use. That is where the UCA braces can help
to reinforce that joint. By capturing the UCA between the thick steel
of the brace and the ball joint (and/or spacer) underneath, you take a
lot of the load off the UCA and keep it from fatiguing. The UCA braces
can also be used with stock ball joints (i.e. without adding the
spacers) for folks who drive their 2WD truck hard without a suspension
lift. YOu can also add the UCA braces after the fact, so to speak, if
you find your driving style has changed. For example if this year you
install the spacers and some larger tires and then next year move to
the desert and find you enjoy bombing down the desert roads at high
speed, that would be a good time to add the UCA braces.
Directly, no. The earlier 2WD control arms and ball joints are a
different design and these spacers will not fit. However, it is
possible to swap in the front suspension from a 1984 or later 2WD
pickup onto an earlier truck. For details, see this thread: http://www.toyotaminis.com/forum/threads/spindle-differences.5309/
If you can swap to the later style suspension, then it should be
possible to install the 2WD ball joint spacers. It'll also be easier to
get replacement parts like bushings, etc. for the later model
suspension as well.
That's a difficult question to answer exactly. There are three main
factors in play. First is the physical geometry of the IFS front
suspension compnents. The second is the ability to align the front
wheels at a given lift height. The third is your "tolerance"
if decreased ride quality as you lift the front end higher.
For the first factor, realize there's only a fixed amount of suspension
travel from fully compressed to fully extended. Ideally your normal
ride height is somewhere in the middle of that range of travel allowing
for sufficient up and down travel so that the front suspension can do
it's job. The spacers will create more travel range by separating the
upper and lower control arms a bit. This delays the contact of the
control arms on the bump stops. You also have to consider the range of
motion on the ball joints and tie rod ends and also on 4WD trucks, the
angle of the CV joints in the front axles. You'll ant to check all thes
components and make sure they're not binding up.
For the second factor, if you plan to drive the truck on pavement a lot
and at highway speeds, you'll need to be able to align the front
wheels. On the 4WD trucks, eccentric cam bolts are used to do this. On
the 2WD trucks, shims are used to do this. There is only so much
adjustment range in those components and once you lift higher than that
adjustment range, you won't be able to fully align the front wheels.
The height at which this limit occurs will vary with the condition o f
the control arms, bushings and adjustment hardware as well as any
previous damage to the IFS sub frame.
For the third factor, realize that the higher you lift the frond end,
the more the ride quality will degrade. You can read this article that
goes into some details. A consequence of the first factor (above) is
that as you raise the front end, you're trading off lift for down
travel. At the limit, you can lift the front suspension to the point
the control arms are in contact with the down-travel bump stops. In
this state, your front wheels will not be able to drop into holes while
driving and instead the whole front of the truck will drop with the
wheels. How the ride quality will limit the ride height will be up to
the vehicle owner. Some folks don't mind a rougher ride, it's a truck
after all, not a Cadillac. Other folks are very particular and won't
tolerate the ride above a certain lift height.
In summary, if you are looking for the most lift you can get, be
prepared to try a few setups. Luckily, it's fairly easy to adjust the
torsion bars and try out various ride heights. Perhaps take
notes on each ride height you try and what the results were and then
work your way up until you find the limit for yourself and your truck.