How To Set Rear Drum Brakes

QUESTION: In the process of performing a smog cheque on my rear-wheel-drive 2000 Mitsubishi Montero Sport, the technician pointed out that the rear drum brakes were not functioning properly. My mechanic discovered that they only needed adjusting.

I had ever understood that rear brake shoes are automatically adjusted each time the brakes are applied while the vehicle is driven in reverse. But I was besides informed by the mechanic that applying the hand brake also serves to arrange the rear brakes. I checked the owner's manual and the Net and could not confirm this.

Can you lot tell me if this is truthful for the Mitsubishi Montero Sport, and how one tin determine what other makes and models have this role?

? Roger Neil

ANSWER: Good question, Roger. Let'south take a quick wait at which vehicles might accept pulsate brakes, then nosotros can address adjusting them. Pulsate brakes were used on all four wheels during the early days of the motorcar. Disc brakes began their rise to commonality in the 1950s on certain European cars, and in the 1960s in the United States. Past the 1970s, disc brakes in front end and drum brakes in the rear became the norm. Now disc brakes on all corners are increasingly common. Larger and lower-tech vehicles may still apply drum brakes in the rear, as does your two-wheel-bulldoze Montero.

One can readily identify rear brake type with a peek through the slots of almost wheels. If a shiny surface is seen, you have disc brakes; a black or rusty surface is likely the face of a brake drum. Vehicles with rear disc brakes may incorporate a small pulsate brake within the center of the brake rotor for the parking brake.

Pulsate brakes crave periodic adjustment; disc brakes do not. Since the mid-1950's, self-adjusting drum brakes accept been the norm, with a slight adjustment correction occurring when needed, as you mentioned, when backing up or applying the parking brake. Some as well self-adjust during forwards stops.

Drum brakes come in a diverseness of configurations, each with its own self adjustment strategy. In general, a larger, typically domestic vehicle self-adjusts when backing up and stopping, and a smaller, typically Asian vehicle self-adjusts during parking brake application or during forrad stops. Consistent employ of the parking brake is highly advised on all vehicles.

During the many years between brake service, a drum brake'southward self-adjusting mechanism can become sticky due to dirt buildup or lack of lubrication and may not advance a "click" as it should when excessive brake shoe travel suggests the need. Symptoms include: poor parking brake performance, when the handle or pedal travel is excessive without acceptable function; a low brake pedal that must be depressed farther than usual; or mild pulling to one side during stops. Manual aligning of the brakes is possible, and once the self-adjusting mechanism is cleaned and lubricated, or perhaps if a worn part is replaced, self-adjustment tin resume.

It'southward interesting that this was noticed during a smog check. With the rear wheels driving the emission dynamometer's giant rollers, the technician likely noticed it was difficult to slow downwardly at the conclusion of the examination. On the route, lazy rear brakes would be much less noticeable, as the front brakes perform the majority of the piece of work.

(Brad Bergholdt is an automotive engineering science instructor at Evergreen Valley College in San Jose. Readers may transport him e-mail at under-the-hood@earthlink.net; he cannot brand personal replies.)

Top Ads

AUTOS

Cabinet Refacing

Cabinet REFACING Existent wood or RTF Laminate Dovetailed drws & Rollouts Finest Mat. & Workmanship Phone call Gary 805-368-9051 Lic#341411

Cars

Cadillac ATS Loses Doors, Gains Style

To say Cadillac has the cross-hairs of BMW's roundel in their sites is an understatement. Cadillac rightly calculated BMW'due south M3/M4 was the primary target for the ATS-V and doesn't mind the comparisons considering ATS-Five is an able challenger. It'due south not perfect yet but all the heavy lifting's been done.|January. 08, 2022

Frontier Pro-4X an Honest Pickup

Wallpaper bores me. I've never been fond of racing stripes to make a car sporty and genuine 4-bike drives shouldn't require a "4x4" label, so the first thing I'd do with this Frontier is hairdryer the wallpaper off the back. Then I might add a few small accessories like trail lights, a burn extinguisher (information technology already has a first aid kit) and a two-way radio for cell-dead zones. And that'due south it…the P4X is a perfectly proficient 4WD pickup.|Dec. 29, 2022

Petersen reopens

After a yr-plus renovation and wrapped upwardly in 100 tons of stainless steel ribbon, Los Angeles' Petersen Automotive Museum has reopened. Expected to cease with a ix-digit toll tag, the museum is home to cars with similar value merely there's more to information technology than that.|December. xviii, 2022

Sprinter van now 4WD

With the influx of slab-sided vans from outside the U.South. information technology's easy to forget the Sprinter—wearing Freightliner, Dodge or Mercedes-Benz badges—has been here for nearly fifteen years. And for 2022 information technology offers four-wheel bulldoze from the factory, the first heavy-duty van to do and then in Northward America.|Dec. 11, 2022