Important Diagnostic Terms For Truck Trailer Repairs

Frequently, when owners bring one or more of their fleet in for truck trailer repairs, various terms are used to describe a problem. It’s not uncommon to hear a thing-a-ma-bob, do-hickey, thingamajig, and more. As far as noises are concerned, you might hear someone refer to clunking, ca-thunk-ca-thunk, popping, chug-chug-chug, and more. Incorrect truck trailer repair terms like that can leave mechanics guessing.

To sound a little more professional and convey your engine/trailer/truck problems to a mechanic more accurately, you might want to consider using some of the below-listed terms. Of course, there are many more terms than this. But it’s a good place to start.


Quite the opposite of hesitation (see below listings), this is a change in engine speed, usually upward, that happens suddenly. Inconsistencies in pressure and fuel delivery are frequently to blame.


You may have encountered a sluggish engine if you’ve experienced either of these when flooring the gas pedal:

  • The vehicle feels jumpy
  • The vehicle barely moves down the road

 What this means is, based on your power input, the right horsepower isn’t being delivered.


From the tires through the steering wheel, this is a pronounced side to side motion. It results from an imbalance of some kind but, in every case, the details can be different. Usually, the guilty culprit can be brake rotors, treads, tires, etc. The mismatch is more noticeable when they are not symmetrical.


When the flow of power is interrupted due to one or more cylinders not igniting properly, this symptom/characteristic of hesitation can occur.


Most often, upon acceleration, this rattling noise is detected. Rather than fuel-burning in one continuous, smooth action, it is caused by uneven fuel-burning. This can also be referred to as detonation.


Hesitation is when you feel a sudden loss of power when you accelerate. The list of causes can be long, but some can be low voltages/weak sparks, poor quality fuel, slow ignition timing, or low fuel pressure.


This occurs when, for a moment after switching off the ignition, fuel still continues to burn and the engine runs. Without a spark, within the cylinder, an air/fuel mixture is combusting. Factors that can be evidenced by dieseling include temperature moderation issues, timing problems, and more.


While trying to change gears, if the transmission slips, your engine might lurch or hesitate. If so, you’ve experienced bucking. Because the engine needs fuel to maintain power, but isn’t getting it, the problem could lie in the fuel line.


Frequently when going over bumps, through the passenger area or the steering wheel, harsh vibrations or excessive noise may be felt/heard. So, where’s the problem here? Because, while driving, road imperfections are mediated by the shock system (i.e., shock absorbers), the issue could lie there.


Though not as common as in the past, these do still occur. The sound is hard to miss and comes from the tailpipe or engine, sounding like a gunshot. Igniting unburned fuel in the exhaust system rapidly combusts, causing not only the backfire but a loss of motion and power.

At Mickey Genuine Parts, our service technicians have a complete understanding of all technical terms involved with truck trailer repair – and some not-so-technical terms, as well. We have certified service centers conveniently located throughout the United States. If you do your own repairs, order parts from Mickey and we will expedite shipping in as little time as possible. Contact us today if you have any questions or would like to place an order.

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