randys blog
How It Works: The Pros and Cons of Spools & Mini Spools
Spools are all about getting full lockup on a budget… 100% lockup 100% of the time. There are two types of spools: full spools and mini spools. Each attains the same objective, ensuring both drive wheels on a given axle receive full torque and rotate at the same speed all the time. They create a solid axle. The Spool Compromise As with any drastic, all-in type of modification, there are compromises along the way. The spool is no different. Since the axles are locked there is no allowance for situations where the tires need to spin at a different speed… i.e. when the vehicle turns a corner. When this happens the tires chirp, sometimes aggressively, as they struggle to complete the turn. The rubber is the weak link. It’s what gives to allow the vehicle to maneuver. In doing so tires absorb a lot of abuse in the form of significant wear. One should also remember even when not pushed to the level of chirping, any imbalance in wheel speed is scrubbed off by the tires resulting in tire wear. Simply put, spools chew up tires. Another compromise is how the binding within the differential also produces undue stress on the axles themselves. In the long term, axles can bent out of shape because of the torsional stress they are subjected to on the street. Changing Driving Dynamics There is a cause-and-effect scenario going on here. In most cases, running a spool will compromise the turning radius of the vehicle. Further, a spooled driveline can be unforgiving driving on wet/snowy roads as it lacks the finesse to handle conditions that call for the management of different wheel speeds to ensure vehicle stability and control. You can roam the online forums and the street-worthiness of a spool-equipped vehicle is a long-raging debate. Due to their unwieldy nature, we recommend spools as an outstanding choice for dedicated off-road and drag racing vehicles only. Full Spool A full spool replaces the carrier, spider, and side gears. The unit consists of a snout and a ring flange. The axles are installed in the snout, which is splined to accept the axle shafts. The spool’s ring flange bolts onto the ring gear. So, the ring and pinion do their job, redirecting torque 90 degrees from the driveshaft to the wheels but the housing has lost its ability to differentiate wheel speeds between the wheels. Yukon and USA Standard Gear spools are made from high-quality 8620 steel and heat-treated for additional strength so your differential is ready for extreme action in the name of ultimate traction. Mini Spool A mini spool is less expensive than a full spool. Since it swaps in place of the spider gears and side gears installation is easier, faster, and cheaper than a full spool. Though Yukon and USA Standard Gear mini spools are constructed from heat-treated 8620 alloy steel they are not as stout as full spools because minis rely on the factory carrier for strength. Cost Versus Reward We see our spools as a safer option for those who are considering welding their gears together to get the same solid-axle traction. The big problem is that welding can be done poorly and fail. Either by weak welds or too much heat which compromises the grain structure of the steel causing the gears to become brittle at the weld point and eventually break. When welded diffs let go they can take other components out… which negates any cost savings of welding. In our eyes, spools are only for dedicated off-road and drag racing vehicles. If the vehicle will see the street we urge customers to consider stepping up to a locker or limited slip differential. Cost Versus Capability You can opt for a Spartan Locker, a helical positraction LSD, or a locker. While each of these products represents a step up in streetability, they also embody a rise in cost. A full spool runs around $320 to $375. A Spartan Locker checks in at $400 to $500, provides full lockup, and although it may click occasionally it is far more civilized than a spool. Our helical positraction limited slip differentials start at $600, seamlessly enhance traction on the street, but do not provide full lockup. Yukon’s Grizzly Locker, an automatic locker / mechanical locker, starts at about $780 and delivers 100% lockup and the ability to automatically unlock when needed. Of course, pricing is application-dependent, but for very little extra investment you can get a Spartan Locker or helical LSD. In many cases, you will save money in the long run by not shredding and buying new tires on the regular. If you run expensive big tires like 35-, 37-, or 40-inchers the savings could be substantial. Spools do what they’re intended to do and we build ours with quality materials and top-notch craftsmanship. But these products are narrowly focused on dedicated purpose-built vehicles that aren’t expected to be driven on the street or even make a 90-degree turn. Seriously consider your vehicle’s usage expectations and consider more than the initial cost. Look down the road, moving up to a more versatile, driver-friendly traction device can be the best call for your wallet and your nerves. Shop Spools
How It Works: Lunchbox Lockers
The Spartan Locker, USA Standard Gear’s lunchbox locker, provides game-changing traction at a low cost. A locker physically joins the drive axles together so they deliver an equal amount of torque to each tire, regardless of available traction. Lockers come in two flavors… selectable or mechanical. What are the Different Types of Lockers? A selectable locker is an on-demand unit that the driver activates electronically or pneumatically via a cockpit-mounted button. A mechanical locker is always active, providing traction 24/7. The Spartan Locker and Yukon Grizzly Locker are mechanical. The Yukon Zip Locker is an air locker or selectable locker that uses a pneumatic system for actuation. The Spartan Locker is flanked by a Yukon Grizzly Locker (left) and a Yukon Zip Locker (right). In mechanical lockers, also called automatic lockers, on-throttle driving conditions, where load is applied to the differential, induces locking. Off-throttle situations, where the diff is unloaded, leads to a partially unlocked unit. When the vehicle turns and the two wheels on the axle turn at different speeds, the unit makes a clicking sound as the square-cut side gears move over and past one another. This ratcheting sound can be loud and is why mechanical units may not be best suited for vehicles that spend a lot of time on the street… it all depends on how sensitive your ears are. What’s for Lunch? The lunchbox locker name is a loose reference to that handy mid-day meal carrier we all know and love. Just as you can put a different kind of meal in your lunchbox, the lunchbox locker allows different internals to be put in your differential… the internals being the lunch and the differential carrier being the box portion of the equation. Lunchbox lockers are not a singular component you swap in, but a collection of parts that converts an open differential carrier (and only an open differential carrier) into a mechanical locker. A typical Spartan Locker consists of a pair of drivers, two spacers, two side couplers, four alignment pins, four pre-load springs, a hardened cross-pin shaft, a roll pin, and installation wires. Depending on the differential carrier design, your Spartan Locker could have more or less components in the box. Pros and Cons of Lunchbox Lockers Great grip on a budget is the lunchbox locker’s calling card. Price is the biggest pro for the lunchbox locker. They cost less than half the price of an air locker, and remember this is before factoring in the cost of a pneumatic operating system. The lunchbox locker is about a third of the price of a large-frame mechanical locker / automatic locker. Going with a lunchbox locker also pays off when it comes to installation. Since the process is less labor intensive than a large-frame locker installing a lunchbox locker costs less. The savings can be even more substantial if you handle the install yourself. The Spartan Locker's patent-pending design replaces the spider gears in a standard carrier case, does not use the thrust washers, and has a revolutionary spring-and-pin design that makes installation quick, easy, and much cheaper that other types of lockers! Further, in some cases, the install does not require the removal of the differential. A disadvantage of this is the lunchbox locker relies on the factory carrier for strength. Large-frame lockers, like the Grizzly and Zip, replace the carrier as a single unit and their case is constructed from a much stronger alloy steel compared to the factory carrier. Being locked all the time, mechanical lockers can cause accelerated tire wear. As with many modifications, it’s a game of trade-offs. Installation Tips and Tricks If you’re able to remove the spider gears with the carrier still in the housing the installation can be done without removing the carrier from the diff. If it’s too tight in there, the diff will have to be removed. Spartan Lockers come with a highly detailed installation manual that includes tons of photos and step-by-step instructions. The manual addresses installation in a variety of differentials. Basically, the Spartan Locker’s drivers are assembled with the alignment pins and springs installed. The installation wires keep the assembled unit together until installation is finalized then they’re removed releasing the spring tension that’s needed to operate the unit properly. Spartan Locker Installation Quick Tips For Use in Open Differentials Only Remember to Re-Install Carrier Shims and Bearing Caps in the Same Place Punch Mark Bearing Caps to Indicate Which Side to Install Them On Be Sure Tires are Same Circumference to Ensure Proper Locker Engagement Are Lunchbox Lockers for You? Vehicle usage is the tipping point. Not just how much your rig will see the street where the boisterous operation of the lunchbox locker comes into play but off-road usage as well. Your expectations on the trail; and how much you’ll be demanding from the driveline come into play. If you’re staying on the trail with moderate hill climbing, scrambling over rocks, and the like, the lunchbox is a good call. If you plan to be more aggressive and looking to get into some extreme situations where a great deal of torque and load shocking are the norm, a large-frame locker may be the way to go. When it comes to the ratcheting and clunking sounds the unit makes, read up on the subject. Some users report the sound isn’t that intrusive, others say the noise fades with use. As we indicated before, the performance game is made of trade-offs… but the payoff is big. Spartan Locker Highlights Big on Traction, Low on Cost For Use in Open Differentials Only Patent Pending Design Replaces Spider Gears Low-Cost Shop Installation - Can be DIY Installed Reliable 100% Lockup Power Transfer Features Heat-Treated 9310 Steel Internals for Enhanced Durability Shop Spartan Lockers or contact us at 866-631-0196
New Product: Yukon High-Capacity Aluminum Allison Transmission Pan
Superior cooling is essential for reliable transmission shifting, whether you're on the road, on the trail, or towing heavy loads. Yukon's high-capacity transmission pan is designed with an impressive 11- to 12-quart capacity and strategically placed ribs to significantly enhance its cooling capability. Made for Allison 1000, 2000, and 2400 series automatic transmissions commonly found in 2001-2019 Chevy 2500/3500 pickups, this transmission pan not only performs exceptionally but also looks the part. It features a durable black powder coat finish, high-quality aluminum construction, a magnetic stainless fill plug, and an additional 1/8" NPT plug. While it might seem like you’ll need to flip your truck to impress your friends, your mechanic will certainly appreciate the innovative design and top-notch quality of this transmission pan. It's a valuable addition for those who demand optimal performance and reliability from their transmission.
How To Use A Dial Indicator
The keys to properly using a dial indicator are precision and patience. The payoff is a long-lasting driveline. The dial indicator is one of those specialized tools that has an intimidating reputation, but as with many things, understanding the components of the tool and how they work is half the game. A dial indicator typically measures the backlash of a ring and pinion gear. It can also be used to measure runout, the untrue movement (wobble) of a rotating object like an axle, cam or crankshaft journal, wheel, brake rotor, or the input shaft of a manual transaxle/transmission. Precision is important because in ring and pinion jobs we are dealing with shims that can be paper sheet thin… as thin as three thousandths of an inch. The first step to dial indicator enlightenment is understanding the workings of the tool. Anatomy Of A Dial Indicator When measuring backlash in a ring gear the placement of the dial indicator is key. High-pinion and low-pinion applications have the drive side gear teeth on different sides of the ring gear. This will determine where the dial indicator is set up because measurements are made on the drive side of the tooth. The Setup A dial indicator is like a high-tech erector set. It can be extended and articulated in an array of angles. Setting up the unit starts with the magnetic base which is placed on the housing and then all the armature is configured to position the tip at a 90-degree angle on the drive gear tooth with the plunger in proper alignment with the gear’s rotation angle. A vast majority of dial indicators have magnets that you position to align the plunger and ring gear tooth. In whatever manner the base of your dial indicator secures to the housing, it must maintain a stable platform because every proceeding step relies on the accuracy and consistency of this starting point. Here, the diff housing makes a great anchor point but other applications may not offer so obvious mounting possibilities. The arm can be moved up or down the main shaft while also being adjusted inward and outward within the housing to more precisely line up the tip and the tooth face. This is where your erector set experience comes into play. There is an adjustment knob behind the dial that allows the dial assembly and plunger to swivel to better match the actuation of the tip with the angle of the gear tooth when the ring gear is moved. The goal is to make as much of a straight line measurement as you can. Tighten everything down to limit flex and be sure the tip is resting on the tooth face… any play or preload in this area will produce false readings. Also, be sure the plunger is not rubbing against the adjacent tooth which may also result in a faulty measurement. Shop Yukon dial indicators and measuring tools here. Measuring You can measure with the existing readout or zero-out the tool by loosening the bezel clamp and rotating the bezel. When measuring backlash on a ring gear be sure you’re only turning the gear and not the pinion which may influence the readout. Clamping or otherwise isolating the pinion is a good idea. When measuring a ring gear, the gear is rotated in both directions to produce freeplay. The amount of the movement is measured as straight-line travel by the tip and plunger. Even the runout of a ring gear can be evaluated by measuring the amount of movement the gear produces back and forth between the thrust bushings. Reading The Dial Most dial indicators have a one-inch stroke, meaning the plunger will only move one inch within the tool. The dial indicator’s range is denoted in the dial. The dial also has units of measure or accuracy indicated, typically in drivetrain operations a 1/1000 of an inch is the preferred unit. The main or outer dial is joined by the smaller revolution counter dial which indicates how many times the needle has gone around the outer dial. So, if the main needle travels around the outer dial twice the revolution dial will read 2. Or 0.200 inches. If the larger needle progresses past zero to 30 on the big dial, the total reading is 0.230 or 230 thousandths of an inch. Total Movement The amount of positive movement and negative movement indicated reveals the total movement. So, the measurement is made from the static beginning with the plunger engaged then it moves inward and outward and the number of units measured in each direction are added together. For instance, if the needle moves from plus five thousandths of an inch to minus 90 thousandths of an inch, the total needle movement is 15 thousandths of an inch. Additionally, if the needle moves 10 thousandths of an inch to the negative side and then five thousandths of an inch to the positive side the total movement is again 15 thousandths of an inch. Once you successfully set up the dial indicator measuring other gear sets will be super easy as long as they have the same pinion arrangement i.e. high pinion or low pinion, as the basic setup of the tool’s armature has been established and you’ll only need to fine tune the tip-to-tooth relationship. Dial indicators deserve a place of honor in your tool case. They expand our capacity, allowing us to do more jobs. They add quality to our work, by enhancing the accuracy of our actions. The end result is a job better done that will last for years to come, a win-win in anyone’s book. Shop Yukon Differential Tools
Yukon Total Takeover
The Yukon Total Takeover, a nationwide one-day event held March 18, afforded shops the opportunity to provide special pricing on Yukon gear sets and installation. More than 50 shops participated in the program. The Takeover was the culmination of eight weeks of hard work and coordination, developing a program that highlighted both Yukon parts and the skill and competency of participating shops. The shops were also able to create awareness for their business on a regional and national level. It was a successful day as many shops offered live music, raffles, meet and greets, and more for their local communities and as a result, are now booking and extending discounts weeks past the event date. Keep an eye out for the next Takeover and be ready to get involved.