AUTONET TV

Differential Service

When you're driving and turn a corner, you probably aren't aware of all that's going on with your wheels.  The outside wheels have a longer distance to travel than the inside wheels, so there are gears that allow the wheels to go at different speeds when you turn. 

That set of gears is called a differential.  In front-wheel drive vehicles, it's by the transmission and called a transaxle.  Rear-wheel drive vehicles have the differential, naturally, on the rear axle. Many all-wheel and four-wheel drives add a center differential since power has to go to the front and rear wheels. (Some newer vehicles power wheels with electric motors, but that's a whole different story.)

Time and distance traveled eventually can take their toll on the differential, and you may notice some noises you hadn't heard when your vehicle was newer.  Sometimes you'll hear a whir that might change in pitch when you turn.  You may hear clicking sounds when you're moving.  Others describe rumbling sounds coming from underneath during a turn. Another symptom of possible differential problems may be vibrations or shakes the faster you go. 

All of these could be signs that you have problems with a differential. One common cause of differential problems is the gears aren't getting enough lubrication.

These can all have serious effects on your driving.  You may find it hard to turn, or your wheels may lock up. That could put you or drivers around you in a dangerous position. 

It's better to take care of differential problems before they get too serious.  Bring in your vehicle so we can have a technician check yours out.  They can see if there are any differential fluid leaks or failing gaskets.  In some cases, we may recommend your differential fluid be replaced.  And if there are any mechanical issues, some components may need to be replaced as well. 

When your differential is maintained, you'll be doing your vehicle a good turn.  

Hill's Auto Repair, Inc.
22829 colton point rd
Bushwood, Maryland 20618
301-769-2400

Don't Blow a Gasket! (Valve Cover Gasket Replacement)

When you head out to your vehicle after it's been parked and notice oil leaking underneath it, that's something to have looked at right away.  Oil leaks mean your oil level is probably low and running a vehicle in that condition can lead to expensive repairs.

While there are many reasons oil leaks develop, one possibility is a bad valve cover gasket.  Vehicle engines have a cover bolted over the spot where the engine valves are, and that cover keeps the oil inside the engine. In between the cover and the engine is a gasket that keeps that seal tight.  But after many years of high engine temperatures and vibrations, that gasket or the bolts that hold on the valve cover can fail or loosen, and oil can leak.

You may see dirty oil on the valve cover in the engine compartment, near the spark plugs, or around the bolts that hold the valve cover on.  All those are signs of leakage and time to bring your vehicle in for our technicians to check out.

In some vehicles, taking off the valve cover and replacing the gasket is a relatively easy job. In some models, though, other engine parts are located near that part of the engine and must be removed to get at the gasket, so repair costs can vary widely.

The technician will measure to make sure the valve cover isn't warped so it can be reused. If it is warped, they'll recommend replacing it with the gasket.  

While the technician has that area of your engine accessible, they will also check to see if other components need replacing at the same time, which could save you money.  And because valve cover gaskets usually fail in older vehicles, the technician will check for other oil leaks then, too. 

One of the best ways to be sure your valve cover is doing its job is to have your vehicle regularly maintained.  The technician will periodically look over your engine compartment and make sure you know when things are showing signs of age and wear BEFORE they fail and leave you stranded.

Hill's Auto Repair, Inc.
22829 colton point rd
Bushwood, Maryland 20618
301-769-2400

Snake in the Engine (Serpentine Belt)

There's a belt that snakes through your engine.  It's even named for a snake, the serpentine belt.  It'll bite you when it breaks, possibly leaving you stranded.  So, it's good to know a little about this snake-like belt.

In early engines, there were lots of belts. They were used to convert the rotating power of the engine to turn a mechanical part.  But engineers had an idea.  Why not consolidate all those belts into one that ran a bunch of different parts simultaneously? Voila!  The serpentine belt.

It's found in the front or side of your engine unlike older belts which were often in a V shape, the serpentine belt has ribs on it which more effectively connect with the pulleys that power the other components.  A serpentine belt may power the water pump, power steering pump, alternator, and the air conditioning: all from one crankshaft. 

Now, all that's fine when everything is working well and the belt is intact.  But when a serpentine belt wears, gets loose, or breaks, it can affect many engine components at once.  Not an ideal situation. 

If you hear squeals coming from the engine compartment, see a battery light, or the engine overheats, those could be signs that your serpentine belt needs replacing.

The good news is that they usually last a long time, from 60,000-100,000 miles or 100,000-160,000 km.  Still, they don't last forever, and your vehicle's manufacturer usually recommends replacing them when they've gone close to the expected maximum.  It’s also recommended that you replace the pulleys and belt tensioner at the same time as they have the same service life. Regular maintenance and inspection of the serpentine belt is not only a good idea; it’s one of those things that you should not let "slip" by.

Hill's Auto Repair, Inc.
22829 colton point rd
Bushwood, Maryland 20618
301-769-2400