Four warning signs that your truck transmission could be about to fail

broken down vehicle busy highwayTruck and bus drivers put a lot of faith in their vehicles and especially their transmissions. This delicate component is solely responsible for turning all of that engine power into miles per hour.

Without one, you are going nowhere. We all know the sorry site of a truck or bus sat solemn in a layby, bonnet flapped open, stranded.

Transmission manufacturers build their reputations on the reliability. Buying products from a trusted manufacturer means you can relax a little bit, but even the most well engineered gears cogs will come loose eventually.

And if unexpected maintenance issues do arise, then it’s best for them to emerge when you’re close to a well-stocked workshop, instead of in a freezing layby off the M25.

Fortunately, there are a number of warning signs which can indicate problems on the horizon.

Dashboard warnings and error codes

First and most obviously, dashboard warning lights and bespoke error codes are ace at predicting failures. Some of these warning lights are easily ignored, especially when your dashboard is lit up like a Christmas tree and the vehicle still seems to be functioning ok. But it is critical that you check them out as soon as possible (especially if they look important).

Aside from the normal warning lights, many of which are quite self-explanatory, many ZF products come with an error code reporting system. These report problems as a collection of numbers and letters. There are an awful lot of these so it is recommended that you keep a transcript close by so you can address a fault as soon as possible.

Serious faults which are ignored or otherwise get left usually ending up costing drivers more in terms of time and money wasted on replacing a unit which could have been repaired.

Unusual gear noises

When you drive commercial vehicles for a living you grow accustomed to the sounds of your vehicle. And this connection can come in very useful for when you diagnose a problem with your vehicle.

One of the most obvious examples of this is when your bus or truck begins to make a ‘funny’ noise when changing gears. Often it’s a buzzing, a clanking or a juddering sensation when shifting up or down. One common fault we hear is of an engine ‘bump’ when shifting to neutral. Sometimes you won’t be able to describe a fault but you know it’s there. We like to think of this as the truck driver’s sixth sense and we take it seriously.

Burning smells

To diagnose a fault early on you often have to rely on all five of your senses. One to add to your sight and hearing is a sense of smell.

Your nose can alert you to parts which might be running to hot and damaging parts of your engine. All vehicles use transmission fluid to bring down system temperature but if that fluid leaks and overheats it can cause irreparable damage. If you smell burning or a ‘hot’ smell then it could be a fluid leak. This kind of problem should be investigated straight away at the side of the road.

Badly behaving gears

Your sense of touch is also crucial in anticipating transmission failures. When gears begin to feel a little heavy or if you find yourself putting extra force into gear changes it might well be a transmission problem. Worse, if your vehicle slips out of gear then it should be taken to a workshop as quickly as possible.

Again, drivers who know their vehicles well will likely be able to spot more subtle changes in how gears feel. These might be important or they could be inconsequential.

If concerned its best to seek the advice of an expert. Our technical team are always on hand to answer transmission questions. Importantly we can offer advice on how serious an issue is so you know if you can wait to get it checked or if it needs addressing immediately.

Call 01204 701 812 to speak to an Ecodrive engineer.