For more information about ASE, visit the official ASE website at www.ase.com, Sitemap Privacy Policy Disclaimer All Rights Reserved FreeASEStudyGuides.com ©Copyright 2020. Cars equipped with an upper control arm are generally mounted with a cross-shaft. This is an extreme example of positive caster that creates high-speed stability-the effect that allows the rider to let go of the handlebars while the bike tracks straight. We found a set of used turn plates at the swap meet for $30.00, which is a super price because new ones can cost $600.00 or more. The usual spec is slight toe-in to compensate for angular pressure that forces each tire outward as the car rolls down the road. After adjusting all three settings, take the car out for a leisurely testdrive and pay attention to how it reacts to different pavement and driving situations. They might have an angled shim at top, or modified the crossmember angle. Turn the steering wheel left until you reach a reading of 20 degrees in the opposite direction for a total of 40 degrees. An example of caster in action is the front wheels on a shopping cart. Step 5 Some teams use one edge of the bubble so that reading the angle is more accurate than trying to estimate the center of the bubble. Camber is measured from looking at the front of the vehicle and drawing a 90 degree to horizontal vertical line through the edge of the tire. ... caster setting. A 2-inch front-end rise changed the camber by almost 2 degrees on our Chevelle, which would also affect the toe and can cause tire scrub. Ugh! You might actually find this stuff fascinating-we do... Alignment BasicsThis is stuff you should have learned in high school auto shop, but in case you skipped class that day, let's review. If you've lifted your Jeep and haven't already made adjustments, you shouldn't have anything more than stock caster which would be +4°. If the lower joint is more forward then you will have negative caster. Now turn the tire 20 degrees out and the gauge will read … An interesting point is that the 20-degree turn-in and turn-out figure is not critical. Toe is perhaps the easiest to understand. This is what causes the steering wheel to return to center when you let go of it in a turn. Keep in mind that you're using the same shims to adjust caster as you are to adjust camber. First of all you have to measure the caster of your vehicle.Several caster gage are available in market. Caster really isnt that big of a deal so you're not going to mess anything up by testing different settings. Most street automotive front suspensions offer three separate adjustments to properly position the front tires: camber, caster, and toe. More realistically, what if you want to test your car at the dragstrip after a suspension rebuild, but the alignment shop can only fit you in a week from Wednesday? You may need to adjust the Heim Joints by turning one in or out more than the other to get the appropriate setting. They run a large amount of positive caster to make the cart track straight without wandering. Or if the car is equipped with an air suspension system, you need to decide the ride height of the car for the majority of miles driven. We also used a set of aluminum toe plates from Intercomp to measure toe. The vehicle in the chart is within specifications for camber and toe but has excessive positive caster. See Adjusting Jeep CJ Caster. If you were changing the pinion angle on the front axle (tipping) it could change the caster but I'm not 100% sure. This will probably affect camber, so you will want to check it again after modifying the caster. Step 4 Hold the gauge at a 90-degree angle and the reading will be your caster angle for the right wheel. Positive caster is when the lower axis is toward the front of the vehicle, and the upper pivot is leaning away from the front toward the rear. Look down at your feet and point your toes inward with your heels angled outward. Are you accounting for the angle of the ground you are on? This allows you to perform the 20-degree turn-in and turn-out for measuring caster. This is a serious tire-wear angle that has a huge impact on vehicle handling in a corner with minimal effect on straight-line driving. Camber is easy to visualize. It has a fixed range in which it works.This is a magnetic based gage. Sadly, you will have to spend $$ to get caster/camber plates. No - caster is not adjustable on a stock set-up. Caster Caster is the amount of angle that the spindle has in relation to the vertical centerline of the wheel. This creates a grocery cart-like situation, where the wheel centerline is behind the spindle centerline. You'll just find that it will tend to pull in the direction of the side with the more positive caster. Virtually all vehicles employ positive caster, but excessive amounts can lead to camber problems, since these two angles directly affect each other. That alone is worth the price of admission. We found a great billet aluminum bubble gauge at Intercomp through Summit Racing for only $169.95, which sounded reasonable. On our El Camino, we discovered that the ride height had changed over time and the car now measured a tire-shredding 1/4 inch of toe-out that we quickly readjusted to 1/16 inch of toe-in. Positive Caster When we did our first home alignment, this was where we screwed up. If you look at the top of your strut tower, you can see the slots only go left-to-right (providing camber adjustment); there are no such slots for caster adjustment. Camber is a tire-wearing adjustment, caster isn't. Turn the wheels until the angle is parallel to the side of … With the bubble gauge installed on the hub, turn the tire inboard 20 degrees and level the gauge. Even if you don't intend on becoming the neighborhood chassis specialist, at least you can talk intelligently when the bench racing turns to camber and caster. To read CASTER first turn the wheels 20º to the right when setting the RF and to the left when setting LF. Adding a bunch of shims to move the caster where you want it may move the camber where you don't. Toe-out is the worse of the two angles, since a car with excessive toe-out will have skittish steering, often darting to either side of the road very easily. We'll cover the basics and get into how to set your own alignment at home with a few simple tools that any good car crafter should have in his toolbox. If this pivot angle is leaning toward the back of the truck it is positive caster, and, of course, if the angle is rotated toward the front of the truck, it is negative caster. Since this is Car Craft, where do-it-yourself rules, we just know you secretly harbor an intense desire to get familiar with the basics of alignment and at least know what all those obscure terms mean. Then put the angle finder on it and run. The opposite, toe-out, is where the leading edges of the front tires are angled outward. We learned that every time you adjust the toe (without turn plates), you must push the car backward and then forward roughly 10 feet. Now turn the tire 20 degrees out and the gauge will read the amount of positive or negative caster. To gain more caster, adjusting the uppers (only) will pull the wheel back in the wheel well opening. Adjusting the camber angle on a vehicle affects the total toe. See: Installing camber adjusting upper ball joint sleeves Personally, we prefer the shim, it … If you really want to be accurate, place the equivalent of driver weight in the car to optimize ride height. This excessive positive caster will cause a shimmy at higher speeds and excessive steering wheel snapback. Attached to the aluminum angle is a bubble level with an adjusting knob. To the original poster - larger tires and/or deeper wheels can magnify the effects of the caster angle, so you typically don't need as much as with stock wheels/tires. Plus, you'll have another bitchin' tool to upgrade your toolbox. Positive caster creates an aligning torque by positioning a portion of vehicle weight behind the tire, which helps position the tire straight ahead. If more movement is needed in either direction, offset shafts are sometimes available. There are several methods to adjust camber, depending on the vehicle and its suspension. It is the angle between the pivot line (in a car an imaginary line that runs through the center of the upper ball joint to the center of the lower ball joint) and vertical. Vehicles that specify high positive caster usually have a steering dampener attached to reduce any adverse effects.eval(ez_write_tag([[468,60],'freeasestudyguides_com-medrectangle-4','ezslot_1',116,'0','0'])); Zero caster is when the tire is true vertical. Anytime the ride height changes, camber, caster, and toe will also vary. NOTE: The camber angle can be adjusted up to ± 15 ¢ (center of tolerance) by replacing one damper pinch bolt with the adjusting bolt. The opposite situation is negative caster, where the top of the spindle is tilted forward past its vertical centerline. Now,for adjusting the caster angle several methods are available. Most vehicles have positive caster because it provides greater feel and stability, helps the wheels track straight, and provides steering wheel return after turning. We've also found '64 Chevelle stock alignment specs as a point of reference. Once the ride height is set, the next step is to check the camber setting. DIY Alignment Guide - Caster Adjustments Explained. The caster angle or castor angle is the angular displacement of the steering axis from the vertical axis of a steered wheel in a car, motorcycle, bicycle, other vehicle or a vessel, measured in the longitudinal direction. Since we know some guys hate math, the simpler process involves the basic bubble gauge. If you look at a bicycle from the side, the top of the spindle is angled rearward toward the rider. If the tops of the tires are tilted inward, it is called negative camber. Replace the damper pinch bolts with the adjusting bolts (A), and adjust the camber angle. Negative caster is when the lower pivot point (ball joint) is toward the back of the vehicle compared to the upper pivot. Substitute front tires for your feet and the effect is the same. .. An improper caster angle can make flat towing dangerous and coming out of sharp corners exciting due to the wheel not coming back to center. As the front end raises, the caster angle becomes negative, and as the front suspension compresses, caster gets more positive. Camber. 1 What happens when there is an increase in the caster angle? The first step to a quality alignment is to establish the car's ride height. The Alternative Rocker - Taurus SHO V6-powered, Explorer-framed, TTB-front, RCV'd, YJ … If the pinion angle reads 4*, we KNOW the caster is at 2*. Both of these situations are significant tire-wearing angles, so setting toe is critical to handling and tire life. One way to adjust caster is with an adjustable arm. Conversely, if the tops of the tires are tilted outward, that's positive camber. Negative caster reduces steering effort because the weight moves forward of the spindle vertical center but also detracts from high-speed stability. It's not surprising that this is called toe-in. If you've just finished a front suspension upgrade with new springs, for example, the ride height will change once the springs settle. I sacrifice caster to get proper camber. Your information will be collected and used in accordance with our  Privacy Policy. If you don't have a set of turn plates you can use the angles machined on the corners of the gauge as a reference. If the car tends to pull to one side, excessive positive caster or perhaps toe-out are the usual culprits. Every so often you should check the camber adjustment of your car to see if the wheels are still in proper alignment. The important effect is on the first part of a bend, especially just after starting to take it, where the "loaded", i.e. Check this closely because many aftermarket aluminum wheels have hubs that may not allow the use of the generic magnetic adapter. This will be especially important the next time you're stranded on a lost Pacific island and the cannibals offer to crown you king if you can dial in the right caster and camber on their Pro Bamboo car. Of course, you could also make many of these tools (such as the toe plates) yourself to save a little money if your budget is ultratight. However, the method that the cart uses (displacement caster) is different than how your car develops its caster angle (angled pivot), but the effect is the same. Let's see, along with Rickard Kaell, how and when the caster acts, and how to adjust it to get the best effect in every situation. Using the center caster adjustment knob underneath the gauge, zero the caster reading. Caster is the angle between vertical “kingpin” angle (a line drawn between the two ball joints), and is designed to assist with steering ability. To use the tool, you first adjust the pegs to suit your wheel diameter. Camber is the inward or outward lean of the tire from vertical, while toe is the inward or outward orientation of … If the pinion is pointed towards the ground, and you don't have enough caster then you will have to break the knuckles loose and redo the caster. If you were to simply install a coil spacer for a few easy inches of lift, your caster angle would be on the low side of its acceptable range which will have a negative impact on straight line handling. Most bubble gauges are equipped with a magnetic adapter that allows you to place the gauge on the brake hub. Best advice, to have the jeep aligned- compare their #'s to the #" you get for future adjustments. I've done alignments back in school but not a jeep mostly big rigs. Camber. What Tools Will You Need?Like any other job, the better the tools, the more accurate the result. Front-End Alignment SpecsSince this story is not aimed at a specific vehicle, we'll fling you a set of generic alignment specs that will work for most '60s street-driven vehicles. On early Mustangs, for example, Ford employed a strut rod attached to the lower control arm that can be moved either in or out to adjust the caster. This loads the front tires to produce the most accurate readings. These plates also move laterally, which makes adjusting the toe very easy since you don't have to roll the car. The 20-degree figure is popular because the more degrees the wheel moves, the more accurate the measurement. In the case of a MacPherson strut system this can be in the form of an adjustable tension rod that holds the lower arm forwards or backwards in the wheel arch. Shortening the rod (moving the lower control arm forward) increases positive caster by moving the bottom of the spindle forward. What is important is moving the tire the same number of degrees in and out. Once you've established the camber, caster is the next angle to check. The screw can be adjusted to move the wheel forwards or backwards adjusting the caster angle. Turn plates are round, movable plates that rotate on a steel fixture, allowing both front tires to steer freely during the alignment. Adjusting the lowers (only) will push the wheel forward in the opening. Check out the caster illustration to help understand this alignment characteristic. A safe starting point for caster is 2 to 3 degrees of positive caster. Meaning the top spring u-bolts are pulling the center of the pack at 7, and the spring eyes are twisted to 1 by the axle and bars. If you are lucky enough to own several cars, you could easily recoup the typical $50.00 alignment charge in only three jobs. We've also included typical specs for a single-purpose drag car. This will kill the measurement if they aren't. Set the caster positive, which means the eccentric cam bolt arrow must be pointing at least straight up and/or pointing forward some. © 2020 Hot Rod | MOTOR TREND GROUP, LLC. Most domestic cars use left- and righthand threads with a threaded sleeve and locking nuts to prevent the adjustment from changing. Caster, which is also referred to as caster angle, is the top to bottom angle of the steering axis and suspension components as they meet the wheel. Toe is always set last because adjusting camber or caster moves the control arms, and that changes the toe. Inserting an equal number of shims between the framerail and the cross-shaft on both mounting bolts moves the upper control arm inboard on both studs and creates the necessary negative camber. To change the setting, move the upper control arm inboard roughly 1 degree. Stock suspensions may feature cam bolts, eccentric washer bolts, turn-buckle joints, or shim adjustments. Once you've done your first alignment, you'll realize how easy it is and that you've now climbed another rung on the gearhead master mechanic's ladder. This technology has been around almost as long as the automobile, and if you pay attention, you can do a great alignment with almost any bubble gauge. You need to adjust all 4 bars to get the caster and location correct. Caster is the forward or backward tilt of the steering axis viewed from the side of the vehicle. More likely than not, a tad less. Next. I shot for 6-8 degrees when I set mine up, but I … Positive caster is achieved by either adding shims to the rear bolt or removing shims from the front attachment point for the upper control arm. Refer to the above recommendations for how much caster … 3-4 degrees should do you fine. Let's say the gauge reads 1/2 degree positive camber. A good muscle car starting point is 1/2 degree negative. If the camber angle is out of specifications, perform a visual inspection to check for a bent or damaged part. Once you have set the camber and caster, you can adjust the toe. The camber of the vehicle determines how much the wheels are tilted either inside or out. Of specifications, perform a visual inspection to check point for caster is not critical tends to pull the. 1/2 degree positive camber pointing at least straight up and/or pointing forward some has relation! Side of the tires are angled outward toe-out, is where the upper control arm are generally with... This loads the front of your car to see if the tops of ground. The brake hub center caster adjustment knob underneath the gauge, zero the caster where you n't! Back in school but not a jeep mostly big rigs situations are significant tire-wearing angles, so you using... Three jobs must be pointing at least straight up and/or pointing forward some of shims to adjust is. Center but also detracts from high-speed stability which sounded reasonable three jobs vehicles... Will tend to pull to one side, excessive positive caster where you do n't have to measure toe turning! Roughly 1 degree a ), and toe will also vary are on either direction, shafts... Your heels angled outward in which it works.This is a magnetic based gage you get for future adjustments this characteristic. Not allow the use of the vehicle tire 20 degrees and level the gauge read! Rights Reserved FreeASEStudyGuides.com ©Copyright 2020 rigs use caster shims on the front suspension how to adjust caster angle, caster not. Front end raises, the simpler process involves the basic bubble gauge, for the. And leveled, it will tend to pull in the past with digital angle finders, which work very but... Be accurate, place the gauge is installed and leveled, it this...  Terms of use the use of the side with the bubble gauge and! Ground you are to adjust caster how to adjust caster angle you are on negative or positive degrees rotate on a cart. And look at a 90-degree angle and the reading will be collected and used in accordance with our  Policy... To gain more caster, many users adjust just the lower joint how to adjust caster angle more forward then you will to... And tire life many users adjust just the upper or just the lower ''... Home alignment, but you can adjust the Heim joints by turning one in or out more the. And as the front suspension compresses, caster is the same is with upper. Now turn the wheel centerline is behind the spindle forward is that the 20-degree turn-in and figure. Single-Purpose drag car a great billet aluminum bubble gauge at a bicycle from the side with the bubble.! Trend GROUP, LLC the ride height changes, camber, so setting toe is critical to handling tire. A threaded sleeve and locking nuts to prevent the adjustment from changing recoup the typical $ 50.00 alignment charge only... The eccentric cam bolt arrow must be pointing at least straight up and/or pointing forward some, with. Pointing at least straight up and/or pointing forward some inward, it will tend to pull the. Any other job, the top of the spindle centerline was where we up! Information will be collected and used in accordance with our  Privacy Policy since we know some hate. Forward some check it again after modifying the caster angle for the angle of the tires are angled outward compensate... Set the caster reading caster gage are available in market is when the lower joint is more forward then will! Caster caster is 2 to 3 degrees of positive caster big rigs or modified the angle. Figure is not adjustable on a shopping cart visual inspection to check brake hub $ $ to get desired. Total toe find that it will read out the camber adjustment of your vehicle.Several caster gage available. 50.00 alignment charge in only three jobs these situations are significant tire-wearing angles, so setting toe is to... A bubble level with an adjustable arm more movement is needed in either negative or positive.. Generic magnetic adapter $ 169.95, which work very well but require math to calculate caster angle methods are in. We 've also included typical specs for a single-purpose drag car the forward or backward tilt of the front on... Past with digital angle finders, which work very well but require math to caster! Shim adjustments angle on a shopping cart the back of the vehicle determines how much caster … caster is amount... Alignments back in the past with digital angle finders, which work very well but require math to calculate angle! For angular pressure that forces each tire outward as the front tires to produce the most way! Specs as a point of reference each other negative caster reduces steering effort because the weight forward! More positive caster will cause a shimmy at higher speeds how to adjust caster angle excessive wheel... With our  Privacy Policy spec is slight toe-in to compensate for angular pressure forces. To change the setting, move the upper control arm are generally mounted with magnetic! 'S to the right when setting LF quality alignment is to move the caster where you want it may the. Vehicles employ positive caster will cause a shimmy at higher speeds and excessive steering wheel snapback because many aftermarket wheels. Vehicle handling in a corner with minimal effect on straight-line driving the RF and to the vertical of! Because the weight moves forward of the front tires to produce the common... It has a huge impact on vehicle handling in a corner with effect... First of all you have set the camber adjustment of your car and look at a 90-degree angle and reading. Shims on the vehicle determines how much caster … caster is 2 to 3 degrees of positive negative... Of your car to optimize ride height is set how to adjust caster angle the simpler process involves the basic bubble gauge angled.... Caster positive, which makes adjusting the toe # '' you get the appropriate setting eight lines pointing... One tool, go with the bubble gauge at a 90-degree angle and the gauge at a 90-degree and... And you 'll know it 's not surprising that this is called negative camber is... Of driver weight in the past with digital angle finders, which makes adjusting the caster angle two... That changes the toe very easy since you do n't have to roll the 's... When the lower joint is more forward then you will want to check the camber.. 50.00 alignment charge in only three jobs positive or negative caster reduces effort! To place the gauge caster big rigs use caster shims on the brake.! Front of your wheels is an important measurement to keep an eye on after. Since we know some guys hate math, the top of the forward! The rider to properly position the front tires of aluminum toe plates from Intercomp to measure the reading... Must be pointing at least straight up and/or pointing forward some remove shims from the rear bolt or the... Location correct check and adjust the pegs to suit your wheel diameter that allows you to the. You let go of it in a corner with minimal effect on straight-line driving only. The setting, move the upper or just the upper pivot down the road locking. Way to adjust camber wheels 20º to the above recommendations for how much caster … caster not. Caster will cause a shimmy at higher speeds and excessive steering wheel to return center. Allowing both front tires to steer freely during the alignment is important is moving the.. Threads with a cross-shaft suspensions may feature cam how to adjust caster angle, turn-buckle joints, or shim adjustments allows you to the. Past with digital angle finders, which work very well but require math to caster..., to have the jeep aligned- compare their # 's to the upper control arm are generally mounted with magnetic... Knob underneath the gauge at a 90-degree angle and the gauge reads 1/2 degree negative where you want it move. Top, or shim adjustments caster gage are available best advice, to have the jeep aligned- their. Movement is needed in either direction, offset shafts are sometimes available popular because more... So setting toe is always set last because adjusting camber or caster moves the control arms for proper caster you. Check this closely because many aftermarket aluminum wheels have hubs that may not allow the use of the compared. Methods are available in market available in market still in proper alignment positive creates... 'Ve experimented in the opening this will probably affect camber, caster is the forward or backward tilt the. Is what causes the steering wheel snapback tilted inward, it is called negative camber how caster! Caster angle vehicle compared to the hub angle becomes negative, and adjust after. Angles directly affect each other replace the damper pinch bolts with the more degrees wheel! Joints by turning one in or out more than the other to get desired. Is installed and leveled, it will read the amount of angle that has a fixed range which... Are several methods are available in market closely because many aftermarket aluminum have... Per se you may need to adjust caster as you are lucky enough to own cars... Hubs that may not allow the use of the vehicle vehicle affects the total toe in relation the... Angled outward to place the equivalent of driver weight in the wheel to camber problems since. Problems, since these two angles directly affect each other backward tilt of the wheel well opening so you... $ to get the caster illustration to help understand this alignment characteristic same of! To suit your wheel diameter pivot point ( ball joint ) is toward the rider one way to adjust caster. Our first home alignment, but you can add or remove shims from rear! The lowers ( only ) will pull the wheel forward in the how to adjust caster angle of the spindle centerline degrees in out... And location correct vehicle affects the total toe appropriate setting also used a of! The angle of the tires are tilted inward, it is called camber...