Sometimes cars develop a language of their own and, after they’ve been in your possession for a while, you become attuned to it, even if you don’t know what it means.
Technicians have to be multilingual in car speak, but the average owner isn’t — they just know what seems normal and what doesn’t.
One of the more “vocal” parts of the car is its transmission; and being able to interpret some of what it’s saying can save thousands of dollars in costs.
Warning signs of a sad transmission
As a starting point, think about when the transmission was last serviced. Continuously variable transmission (CVT) or conventional transmissions are hi-tech and so you need to be particular about the fluid you use. Many transmission-related issues can be attributed back to lack of servicing or not using the correct fluid type.
Transmission fluid degrades over time and is also affected by operating heat which can be made worse by towing.
A general rule of thumb is to change the fluid every other year or every 30,000-40,000km. But, if you’re using your vehicle to tow or carry heavy loads, the fluid needs to be changed more frequently.
LOOKING AFTER A VEHICLE IS ALL ABOUT THE SENSES — WHAT YOU SEE, HEAR, FEEL AND SMELL. IF YOU NOTICE ANYTHING THAT’S OUT OF THE ORDINARY THEN WE’D SUGGEST A PROMPT VISIT TO YOUR NEAREST WORKSHOP
Slippery signs
Just like the slipping clutch in a manual transmission, an automatic can slip or flare, particularly between changes.
In the early stages of trouble, or in vehicles without a tachometer, it may be difficult to detect. But, if the engine seems to rev more than normal and it’s no longer matched by vehicle momentum, you may have a problem.
Flaring is where the revs momentarily increase between gear changes due to the accelerator still being depressed, but a delay between gears allows the vehicle to rev before the next gear is fully engaged.
This shouldn’t be confused with CVT transmission operation, where the revs will hold steady while the speed climbs. This can often translate as a slipping sensation, but doesn’t necessarily mean there’s a problem.
A common complaint for CVT vehicles is shuddering when moving off. This can be fixed by changing the fluid and adding an anti-shudder additive — but if more work is required this issue can be expensive.
Rough shifting
This one’s a bit easier to detect as there’s usually a noticeable clonk when engaging drive from park, reverse or neutral.
You might also experience harsh gear changes, disturbing an otherwise smooth drive. This could also be a symptom of a worn driveline component (differential or axle) that needs further investigation.
Delayed engagement
Sometimes there may be a delay in your vehicle’s transmission changing. If you select reverse and accelerate but, instead of smooth movement, the car jolts forward and you hear a slight bang, it could be an indication of low or dirty fluid.
In the worst instance, it could be due to an internal component malfunction.
This is commonly found in used vehicles with high mileage and, until the vehicle can be repaired, you can help prevent further damage by delaying acceleration for a few seconds after the gear has been selected.
Fluid leaks
A total loss of transmission fluid is commonly caused by a split or perished cooler hose and will stop any vehicle dead in its tracks.
Over time, a leak can do exactly the same thing, but it can potentially cause more damage, as the transmission has to work harder to try to maintain drive.
Slow leaks can be from a perished gasket or seal and can spread to look like a combination of leaks. Cleaning the transmission housing will allow you to pinpoint the location of a leak.
Keeping cool
Buzzing noises from a transmission could indicate low fluid. It can also highlight a problem with the fluid not being pumped properly due to a partially blocked pick-up or dented transmission pan.
Burning smells can be caused by an overheated transmission when towing, or it could also be a sign than a component is slipping and failing inside.
Transmission fluid should be clear. If the fluid has turned a dark brown or black, it’s a good indication the transmission has been worked hard.
For this reason an external transmission fluid cooler may need to be fitted on vehicles that tow significant loads. It’s all about keeping the fluid temperature down, particularly on a scorching summer day and in slow traffic.
Looking after a vehicle is all about the senses — what you see, hear, feel and smell.
If you notice anything that’s out of the ordinary then we’d suggest a prompt visit to your nearest workshop.