Even the strongest metal fastener can fail. And it will likely fail in one of six ways. The good news is that if you properly analyze the failed component, you can easily diagnose the reason behind its sad end. And when you know why a fastener failed, you can prevent it from happening again in the future. If we listen to what ARP has to say – and after all, they are a recognized leader in fastener technology – each one of these six different failures can be identified by their unique characteristics. All you need is a three-lens magnifying glass. Once you have a close-up, follow this simple guide to interpret what your fastener’s physical characteristics are trying to tell you.

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FAILURE #1 – TENSILE OVERLOAD

If your metal fastener has failed because of a tensile overload, you will notice: • The bolt will stretch and “neck down” prior to rupture • One of the bolt’s fracture faces will have formed a cup, and the other a cone. To avoid this failure in the future, make sure that your fastener is adequate for the installation. Also take care not to preload beyond the specified yield point of the bolt’s material.

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FAILURE #2 – TORSIONAL SHEAR (TWISTING)

If your metal fastener has failed because it was subjected to torsional stress, you will notice: • An obvious direction of failure • Failure likely occurred in your driveshaft, input shafts, or output shafts • Failure likely occurred during disassembly To avoid it in the future, make sure to lubricate male and female threads, using an appropriate lubricant. And check that the male fastener is properly aligned with the female fastener.

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FAILURE #3 – IMPACT SHEAR

If your fastener has suffered from an impact failure, you will notice: • A flat failure face coupled with clear directional traces • Failure likely occurred in bolts loaded in single shear (flywheel bolts, ring gear bolts) • Failure likely occurred because the bolts had to locate the device, as well as to clamp it To prevent this failure from occurring again, make sure your bolts are sufficiently preloaded on installation. Remember that a fastener’s function is to clamp parts together, and not to locate them. Let dowels take care of it.

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FAILURE #4 – CYCLIC FATIGUE

This failure is specific to popular drag racing fasteners. They are usually manufactured from high strength quench and temper steel alloys that have undergone the process of hydrogen embrittlement. These alloys include L-19®, H-11, 300M, and Aeromet among others. To avoid this type of failure, choose only the highest quality high strength fasteners from reputable brand names. For this type of fastener, extreme care must be exercised during the manufacturing process. Another option is to go with fasteners manufactured from Inconel 718, ARP 3.5 or Custom age 625+, as they are all immune to hydrogen embrittlement.

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FAILURE #5 – CYCLIC FATIGUE CRACKS PROPAGATED FROM RUST PITS

Just like with cyclic fatigue, cyclic fatigue cracks are most common in high strength steel alloy fasteners. Again, these alloys include L-19®, H-11, 300M, and Aeromet. If you’re experiencing this failure, you will notice: • A double origin of the fatigue cracks (first photo) • A juncture of the cracks which propagates from the rust pits (second photo) To avoid this problem, keep susceptible fasteners very well oiled. Make sure that they’re never exposed to any moisture, and that includes sweat. Fasteners made from manufactured from Inconel 718, ARP 3.5 or Custom age 625 are immune to stress corrosion.

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FAILURE #6 – CYCLIC FATIGUE CRACKS CAUSED BY IMPROPER INSTALLATION PRELOAD

This failure occurs when the dynamic load exceeds the fastener’s clamping load. You end up with cyclic tensile stress followed by failure. If your fastener has failed due to an improper installation preload, you will notice: • A clear origin causing the fatigue crack (arrow #1 on second photo) • A telltale “thumbprint” or “beach mark” (arrow #2 on second photo) • Tracks which propagate the fatigue crack outwards (arrow #3 on second photo) When you’re replacing your failed fastener, remember that in most cases you should match exactly what you’re replacing. Choosing a stronger bolt is not always going to solve your problems. Stronger bolts are more brittle and will probably fail in a specific application.

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Canadian weather can be very unpredictable and very harsh. The winter can bring heaps of snow while the summer can sear your vehicle with its intense sun. One of the best solutions for this type of weather is to equip your vehicle and protect your belongings with a tonneau cover. But getting the most bang for your buck is not as easy as you might think. Choosing a functional and durable high quality tonneau cover is just the first step. And that’s because a tonneau cover needs to feel the love. …the love in this case would be properly caring for your tonneau by following our basic maintenance tips…

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What’s the BEST tonneau cover? When you’re choosing a tonneau cover, go with a reputable brand name that you know you can trust. Extang and UnderCover are brands recognized across the world for producing some of the most durable hard tonneaus. Hard tonneau covers are the ultimate in durability and security. Your cargo will be secure from both the elements and prying hands. But with this added protection also comes added weight. The good news is that this won’t result in a drop in your fuel economy. The reason is that hard tonneau covers are actually more aerodynamic than their soft counterparts, which offsets their heavier weight factor. Access, Bestop and Truxedo are top industry leaders for designing and manufacturing some of the most long-lasting soft tonneau covers. Soft covers are easy to install due to their light weight while providing rudimentary protection against the elements. But no matter which cover you decide to go with, you can be sure that TDot has it in stock!

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Tonneau Cover Maintenance Tonneau covers are.. expensive! And when you’ve purchased and installed one, you’ll want to give it the proper care to make sure it lasts through the years. The good news is that regular tonneau maintenance will be simple and inexpensive. And you’ll actually end up saving money down the road. The most important thing is to regularly check your cover for scratches, bumps, dents, lodged debris, looseness and corrosion. If you spot anything out of the ordinary early on, you’ll be able to stop it from snowballing into a costly issue. Inspect all cover mounting hardware, like clamps and bolts, to make sure it’s securely tightened. Because if it’s not, it could seriously damage your tonneau cover. Slide and close your tonneau a few times to see if operates smoothly. And if that’s not the case, lubricate the rails to prevent any unwanted traction and wear. Clean your cover with mild soaps that won’t harm its coat or your vehicle. But if your tonneau is made from vinyl, make sure you clean with a vinyl cleaner for the best results. ..When you’re drying it up, remember to do so with a soft cotton cloth or sponge. And finally, don’t leave heavy equipment or cargo on top of the cover for longer than necessary. This could result in sagging and damage. But if you need to store any gear on top of your cover, make sure to first check the manual for its specific weight ratings. Have any tonneau maintenance tips of your own? Share them with us in the comments!

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Summer is finally here. And with summer comes hot, hot heat. If you want to be sure that your dear offroader, muscle car, or daily driver is not going to suffer a slow, fiery…nightmare, make sure your cooling system is working as it should be. How? Open up the cold beverage of your choice, and run these simple checks.

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CHECK COOLANT LEVELS & ANTIFREEZE STRENGTH

I’ll start you off with the basics. Make sure that you have enough coolant in your cooling system. If your vehicle has a coolant expansion tank, remove its cap and take a look inside. If your water-antifreeze mixture is below the mark, you know what to do… fill up. Some vehicles don’t have an expansion tank, or they do but the tank does not have a removable cap. If this is your case, you need to remove your radiator cap to check your coolant levels. And this requires a few precautions. The most important one is to never, never remove the cap if your engine is hot. If you do, you risk injury from boiling coolant and steam shooting up at you from the filler neck. On a cool engine, release any built up pressure by pressing down on the cap and turning it towards the safety stop. Wait a few seconds before completely removing the cap. Again, if the coolant mixture is below the mark, fill up! But before you cap off, draw up a small amount of coolant with the help of a hydrometer. The device will display your antifreeze strength. And why should you care? Antifreeze is multi-functional and vital to the proper operation of the engine. It works to prevent corrosion, transfer heat, protect from freezing, and prevent any scale build up. And if your antifreeze concentration isn’t strong enough, you should address it.

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CHECK THE THERMOSTAT

The cooling system’s thermostat sits between the engine and the radiator. Its job is to block coolant from the engine when the engine is cold. But when the engine heats up and reaches its operating temperature of around 200 degrees Fahrenheit, the thermostat opens up to let coolant pass through. In this way it decreases engine wear, deposits and harmful emissions. To test if it’s working as it should, heat up a coolant solution to about 25 degrees Fahrenheit over the temperature stamped on the thermostat. Submerge the thermostat – it should open up. Now allow the solution to cool down to about 10 degrees Fahrenheit below the temperature stamped on the thermostat. Submerge the thermostat – it should close. And if your thermostat fails one or both tests, you need to replace it.

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CHECK FOR LEAKS

Examine all cooling system connections to make sure they are tight. Check your hoses by squeezing them. They should be difficult to collapse. If any hoses are soft, worn, rotted or oddly swollen you need to replace them. Otherwise air could find its way inside of your system. It’s trickier to diagnose if exhaust gases are leaking into your cooling system. In most cases, these leaks happen because of a defective head gasket. And if these harmful gases leak into your system, they can corrode its components and even your radiator. You can check for exhaust leaks with the help of an exhaust gas analyzer. Remove the expansion tank cap or radiator cap and hold the analyzer probe directly above the filler neck. Do not submerge the probe in the coolant! The analyzer will inform you if it detects any exhaust gases. Perform a pressure test to find out if there are any other leaks in your cooling system using a radiator pressure tester. Use the same tester and a special adapter to check if your radiator cap is able to hold its rated pressure. If not, it’s loosing coolant. And eventually, your engine will begin to overheat. If the cap is worn you should replace it.

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CHECK THE DRIVE BELT

The water pump and drive belt circulate the coolant inside of your coolant system by drawing it away from the radiator and pushing it into the engine block. It’s important to check both components for any wear or tension. If your drive belt has loosened, the pump won’t be able to turn quickly enough to achieve an optimal circulation of coolant. What could also become a problem is your alternator not turning quickly enough to keep the battery charged. If you’re testing a V-belt, make sure the engine is turned off. Take the V-belt and twist it between your fingers. Inspect if for any cracking, glazing, tearing, or grease. If any symptoms suggest that it’s worn, you should replace it. If your system is equipped with 2 V-belts, but only one is worn out – replace both. This will guarantee proper operation and consistent wear in the future. If you’re testing a serpentine belt, inspect it for fraying, glazing or other signs of wear. Also check its belt tensioner for wear. Regardless of the condition you find it in, a good rule of thumb is to replace it once your engine reaches 150,000 km.

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Both understeer and oversteer are conditions which describe your vehicle’s steering sensitivity. They occur more commonly in racing. And less so in street driving. But understeer and oversteer can also result from harsh driving conditions, or your driving style and driving ability.

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UNDERSTEER Understeer occurs when your vehicle turns less than you commanded with the steering wheel. It’s a common problem in front-wheel drive and all-wheel drive vehicles. This is caused when the front tire drift is greater than the rear tire drift. To diagnose this problem, make a continuous turn by holding the wheel and throttle steady. If your car ends up making a widening circle, you have understeer. What do I do when I understeer? You will probably understeer if you’re carrying too much speed into a corner. And this will inhibit your vehicle from responding to your steering. It will turn less than you want it to. If you find yourself in this situation, simply remove whatever factor is causing the skid. Release the accelerator and lower your speed. Straighten the wheel and allow your front tires to gain back the needed traction. How can I correct understeer? • Raise the front tire pressure or lower the rear tire pressure • Soften the front shocks or stiffen the rear shocks • Soften the front springs or stiffen the rear springs • Lower the front end or raise the rear end • Install wider front tires or narrower rear tires • Soften the front sway bar or stiffen the rear sway bar • Increase the front negative camber • Increase the positive caster

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OVERSTEER Oversteer occurs when your vehicle turns more than what you command it to with the steering wheel. And it’s most common in rear-wheel drive vehicles. The main cause of oversteer is the lack of traction in your rear tires. And when there’s less traction, the drift in the rear becomes greater than it is in the front. This prominent rear drift makes your car spin inward. What do I do when I oversteer? You’re probably driving a rear-wheel drive car. And you’ve probably entered the turn too quickly and your rear tires are slipping. If you use too much power at a sharper steering angle, the resulting momentum will spin your rear around. To counter this, steer your wheel in the direction of your skid. So if you’re turning right and your rear slides left, steer to the left. How can I correct oversteer? • Lower the front tire pressure or raise the rear tire pressure • Stiffen the front shocks or soften the rear shocks • Stiffen the front springs or soften the rear springs • Raise the front end or lower the rear end • Install narrower front tires or wider rear tires • Stiffen the front sway bar or soften the rear sway bar • Reduce the front negative camber • Reduce the positive caster

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With modern stability control systems, you don’t have to worry so much about under- or oversteering. But even the most advanced electronics can’t help you counter the laws of physics. So the best way of avoiding problems is to drive within your limits.

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