It is never pleasing to find out a sound on your car that you don’t know where it comes from. You may be questioning what to do when you identify a reversing gear noise that persists on your smart forfour? Any gearbox problem can be critical, but before making sure, it is better to do a few investigations. Our team has created this article to support you solve it. First, we will see what the origins and the different gearbox noises can be on smart forfour, and second, what are the solutions available to you.
Classical reverse smart forfour noises and some tips to preserve your gearbox
Why does the reversing of my smart forfour make a different noise from my other speeds?
De facto, adding all gears, bearings and pinions into a gearbox is a difficult process. The noise generated by the reversing of your smart forfour is logical. It can be explained in a fairly simple way. In fact, the gears used for conventional speeds (1st to 5th or 6th) are so-called “helical” gears (oblique gears) . The use of such a pinion makes the noise caused by the gears less important than with spur gears used for the reverse gear.
Tips to limit wear on your clutch and gearbox
- Don’t give a big boost:
Certainly, if you kick the throttle hard when you are in reverse or when you put the car in the revs, you risk to burn your clutch or gnawing at the gearbox pinions. - Never reverse while the car is in motion or vice versa:
Reversing the direction of operation of the gearbox during operation is a very bad practice. In fact, the pressure you will apply on the gears will be enormous and you will make a premature wear and tear of the gears. You can even break the gears of your gearbox at speed by doing so. It will therefore be completely common if you notice a reverse noise on your smart forfour if you shift gear under these conditions.
Different smart forfour reversing noises and their causes
Finally in this section, we will move on to what you are probably most interested in this page, to learn about the origin of reversing noise on smart forfour. Here are the 3 typical sounds you may be victim of.
I perceive a grinding noise when starting in reverse gear
If you find out a grinding noise when you start in reverse with your smart forfour, it may be the engine mounts that are tired. In fact, when the engine is in reverse gear, due to the pinions we saw above the vibrations made by the gearbox are higher and it is therefore possible that due to their wear the silentblocks no longer absorb the engine vibrations well. In this situation, do not hesitate to check this content for more info about strut mount noises on smart forfour.
An increased reverse knocking noise on smart forfourX
If you are subject to a knocking noise when you are in reverse with your smart forfour and this noise tends to build up as you gain speed. It is possible that you are going through a serious problem that needs to be fixed rather quickly before wrecking your entire gearbox. In fact, an intensifying rattling noise means that the gears are damaged. If they are, debris will disperse to the rest of the box and damage other gears before long. Take your car to your repair shop quickly or read this content page about gearbox noise on smart forfour for more details.
I hear a noise when I go in reverse
Hearing a noise when you shift into reverse is normal and related to the gears and sprockets used in the gearbox. If, on the other hand, you have the feeling that your smart forfour reverse gear makes more noise than before, it is possible that filings have been produced and are moving around in it. It is therefore time to empty the box.
