SKF is offering RockAuto customers an exclusive 10% instant rebate on their entire line of Wheel Bearing & Hubs through the end of March, 2021!

Wheel Bearing & Hub units are low maintenance parts, but that does not mean they last forever. Potholes, underinflated tires and other hazards can prematurely damage hubs. Common signs of a bad hub unit include:

• Noise:
  • A humming, rumbling or growling noise that increases with acceleration or as the vehicle turns
  • A loud whining or grinding noise when the vehicle is in motion
  • Clunking noises when driving over uneven road surfaces
• Excessive play and vibration in the steering wheel that changes with vehicle speed or as the vehicle turns
• ABS system malfunction

SKF manufactures Original Equipment Wheel Bearing & Hubs for vehicle manufacturers all over the world. Their premium quality hub units are manufactured using high quality steel and surface finishes, premium seals, OE sensors, precision manufacturing techniques and precise assembly tolerances. Every SKF Wheel Bearing & Hub is 100% tested to actual OE specifications for fit, form and function. This means it will fit and function correctly, and last as long as the original unit that came on your vehicle. In fact, in many cases, it is the same one!

Find the SKF Wheel Bearing & Hub unit for your vehicle in the "Brake & Wheel Hub" category of the RockAuto.com catalog. To see details for the SKF rebate and additional rebates by ACDelco, AMS Automotive, KYB, Power Stop and SMP go to the Promotions and Rebates page.

While shopping, watch for the "Promotion/Rebate" next to the part names to help you save even more on RockAuto’s reliably low prices!

ChevroletForum.com is a comprehensive resource and a large community of Chevrolet owners and enthusiasts. This forum is active with friendly members sharing information on all aspects of these cars, trucks, SUVs, crossovers and vans. You will find active discussions, answers to technical questions, and information on gas, diesel, electric, new, classic...if you drive a Chevrolet you will find something useful in this popular forum.

If you are the administrator or member of a forum and you would like to see your website featured in an upcoming newsletter and receive a discount code to share with your members, contact marketing@rockauto.com.

In the summer of 2018, my 1995 Jeep Grand Cherokee was my pride and joy. I had gotten it from a family friend with only 126,000 miles on it, which is as good as new for that 4.0 liter engine. One day I was preparing to change the oil and wanted to get it done quickly since rain clouds were starting to roll in. I drained the oil, popped a new filter on, and set about filling it back up with oil when I felt the first few rain drops. Satisfied with my work, I ran back into the house, only slightly less dry than when I had started.

The next day, I noticed my engine temperature would start slowly climbing when at idle. However when driving at speed it returned to normal. I attributed this to a known worn fan clutch and load on the engine from running the air conditioning. I had known the hot engine issue would need to be fixed but could be managed for now by rolling down the windows and turning the heat on. After grabbing lunch in a drive through and getting to my next worksite, I let the engine idle so I could have air conditioning while scarfing down my meal. I then looked at my temp gauge, and it was fully in-the-red overheating!

I shut the Jeep off, a few moments later, the radiator exploded into a gigantic cloud of steam that engulfed the front half of the car. I popped the hood to survey the damage and found the problem. In my haste to complete my oil change in record time, an empty oil bottle had fallen and gotten wedged between the fan and radiator, and with a worn out fan clutch, nothing was moving any air when at idle. Not a story I will live down anytime soon, but it still manages to get a pretty good laugh amongst my friends.

Brian in Virginia

Tell us about your most infamous auto repair blunder or unconventional fix. Use your woe to help others avoid similar mistakes or share off-the-wall solutions that worked (at least for a while!). Please email your story to flamur@rockauto.com. Include your mailing address and if you would like a RockAuto T-Shirt (please let us know your shirt size) or Hat if we publish your story. See the T-Shirts and Hats under Tools & Universal Parts in the RockAuto catalog. The story will be credited using only your first name and your vague geographic location (state, province, country, continent, etc.) so you can remain semi-anonymous!

Why did Nissan and Toyota rush to add rear doors to Pathfinders and 4Runners in the early 1990s?

A. They wanted to differentiate their vehicles from the 2-door Suzuki Samurai.
B. They wanted to better compete with the 4-door Jeep Cherokee (XJ).
C. They wanted to pay lower import tariffs.
D. All the above

Answer below

The 360 in my '79 Chrysler 300 briefly speaks to me when it has been sitting in the garage awhile. A tapping sound disappears once warm oil lubricates the worn valvetrain. A rattle goes away after the idle smoothes out and the carburetor's heat riser stops vibrating against the exhaust manifold. A nut that held the heat riser to the threaded end of an exhaust manifold stud snapped off a decade or two ago.

Owners of high mileage, late-model vehicles may hear their engines speaking a similar language, but some of the words have new meanings. Exhaust manifold noise may be mistaken for valvetrain noise and vice versa.

Valvetrain Ticking:
The flat tappets in my old Chrysler engine briefly rattle until they are lubricated. Valvetrains in engines built since the late '80s usually have roller lifters that roll across the surface of the camshaft. Noise coming from roller lifters is a more urgent problem.

Roller & Flat Valve Lifter (top)
Exhaust Manifold Studs (center)
Manifold Repair Clamp (bottom)

A steady ticking sound from roller lifters that may increase as the engine warms up could mean a worn roller is bouncing, rather than rolling, across the surface of the camshaft. The roller will loosen further and the bracket that holds it in place might eventually scrape against the camshaft. The roller lifters and likely the camshaft will need to be replaced as soon as possible to reduce the amount of metal debris circulating around the engine in the motor oil.

Exhaust Manifold Ticking:
Exhaust manifold mounting studs (Exhaust Manifold Hardware) are stressed every time the exhaust manifold heats up and cools down. Studs on newer engines can face even more stress because they may hold together aluminum, iron and/or steel parts that all expand and contract at different rates. If a crucial stud or enough studs break, then exhaust will leak past the exhaust manifold gasket, creating a constant tick/rattle noise.

The metal heat shields common on newer engines are typically mounted on threaded ends of exhaust manifold studs just like the heat riser on my old Chrysler engine. If a heat shield is loose, then an exhaust manifold stud has probably snapped. A mechanic's stethoscope can help verify a noise is coming from a leaky exhaust manifold rather than the valvetrain or some other part.

How difficult it is to remove and replace all the exhaust manifold studs and the exhaust manifold gasket depends on how crowded the vehicle's engine compartment is and how many studs have snapped off flush with the surface of the cylinder head.

Exhaust manifold studs are often surprisingly easy to remove if there is even just a small bit of metal to grab onto with locking pliers. Mechanics sometimes weld a piece of metal rod to the end of a broken stud.

People without welders can carefully drill a hole in the broken stud and firmly insert a bolt extractor that provides purchase for pliers or a wrench. Sometimes just the spinning drill bit will be enough to spin loose a broken stud. A small, right angle drill that runs off compressed air or a battery can help with the drilling when space is tight.

For some common engines with hard to reach broken exhaust manifold studs, part manufacturers have thankfully made Exhaust Manifold to Cylinder Head Repair Clamps that use existing bolt holes in the cylinder head to solidly clamp the exhaust manifold in place. The broken stud just stays where it is. The repair clamps are typically available (found under "Exhaust & Emission" in the RockAuto.com catalog) for engines that have stud problems partly because they were installed in trucks driven a lot of miles, such as GM's current 6.0L and Ford's trusty old 460 (7.5L).

Tom Taylor,
RockAuto.com

To read more of Toms articles, click this link and choose from story titles on the Newsletter Archives page.

This is my 1964 Chevrolet Bel Air 4-door sedan with the original 283 engine and Powerglide transmission. We had been looking for a true to character older car to turn into a family cruiser after years of being a little distant from the vintage/custom auto world. And as luck would have it, I ran into a fella that said his mom had something we might be interested in. It was exactly what we were looking for! To top it all off the Chevy was located less than 20 miles from home! Tags on the car had expired in 1997, and think the last time it started was around 2004.

I brought the Bel Air home in April of 2020, and the wrenches started spinning to repair and rebuild the vital systems. The body was in overall good shape so we just buffed the paint and polished the trim but left the rust (for character!). The old engine fired up and was functioning for our first drive in January of 2021. As always there is more to do, but it feels good to see it move under its own power.

RockAuto is ALWAYS a huge help and a money saver for the big and small parts we used for the cooling, drivetrain, electrical, fuel, ignition and suspension systems.

Scott in Tennessee (RockAuto customer for over 8 years)

Share Your Hard Work
Do you purchase parts from RockAuto? If so, RockAuto would like to give you the opportunity to have your car or truck possibly featured in one (or occasionally more) of our publications such as the monthly newsletter, collector magnets, RockAuto social media or other commercial use. New, old, import, domestic, daily driver, trailer queen, classic, antique, we want to see them all! Please email flamur@RockAuto.com with the vehicle history, interesting details, your favorite images (tips for taking pictures of your car) and what parts from RockAuto you have used.

Why did Nissan and Toyota rush to add rear doors to Pathfinders and 4Runners in the early 1990s?

A. They wanted to differentiate their vehicles from the 2-door Suzuki Samurai.
B. They wanted to better compete with the 4-door Jeep Cherokee (XJ).
C. They wanted to pay lower import tariffs.
Answer: D. All the above (The US Govt. had just classified the Samurai as a "light truck" because it only had two doors. "Light trucks" paid a 25% tariff while 4-door SUVs were "passenger vehicles" that only paid a 2.5% tariff. Nissan sued the US Govt. and got the 2-doors=light-truck rule thrown out in 1994. Source: https://www.hemmings.com/stories/2021/03/08/suzuki-wanted-to-call-the-samurai-a-cargo-truck-and-accidentally-created-a-new-way-around-the-chicken-tax)

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