8 Signs of Transmission Problems in Your Medium Duty Box Truck

Mechanical problems in your midsize import truck, as opposed to electrical problems, tend to come with distinct sounds and sensations that will help indicate that something may not be functioning the way it was designed to. After a while, transmissions are bound to start having some problems. Repairs to your medium or heavy duty truck's transmission can be expensive, so it's worthwhile to pay attention to anything that seems unusual.

Here are 8 signs of transmission trouble you should watch out for:

Leaking Fluid
Leaking transmission fluid is probably one of the easiest ways to identify that your transmission needs attention. Automatic transmission fluid is vital to your car's shifting capabilities, so a little fluid on your driveway can quickly turn into a major problem. Automatic transmission fluid is bright red, clear and a little sweet-smelling when everything's working correctly. If the fluid isn't there, or if it's a dark color and has a burnt smell, you will need to replace the fluid or take it to a mechanic.
Unlike your car's motor oil, the transmission doesn't really consume or burn up any fluid during use, so if you notice you're running low on fluid, then it's definitely leaking out somewhere.
If you have a manual transmission, checking the fluid levels may not be as easy as simply lifting the hood and reading a dipstick. Manual transmission fluid has to be checked right at the transmission case -- usually through the fill plug.

Related: #1 Reason For A Slip In A Standard Transmission

Burning Smell
If you start to smell burning transmission fluid it may indicate that your transmission is overheating. Transmission fluid works to keep the moving parts of a transmission lubricated as well as keeps the unit from burning itself up by providing the necessary cooling.
Common causes include low or inadequate transmission fluid, which can indicate a leak or dirty fluid that needs changing.

Transmission Noisey in Neutral
If the car is making noise when in neutral it could be the transmission. As with many of the problems on our list, adding or replacing the transmission fluid will usually do the trick. Keep in mind you should read your owner's manual before decideding which fluid to use.

Refuses to Go Into Gear
Another potential problem is that the transmission refuses go into gear when you press the clutch pedal and attempt to move the stick shifter. It may happen when trying to get into first gear from a stop, or at any point up and down the assorted gears. Common causes include low transmission fluid, wrong viscosity (thickness) of fluid, or required adjusting of the shift cables or clutch linkage.

Feeling Grinding or Shaking
For automatic transmissions, you'll most likely feel the car shimmy into each gear or the transmission will make a jarring transition into the next gear. If you notice anything other than a smooth transition between gears, then you might need to have your automatic transmission looked at for adjustments or repair.

Related: #1 Reason For A Slip In An Automatic Transmission

Gears Slipping
In a healthy transmission, the car stays in gear until a gear shift is intentionally initiated. But on a transmission where the gears slip, the car can spontaneously pop out of the gear it's in while driving and (in a manual) force the stick back into neutral.

Lack of Response
When your transmission hesitates or refuses to go into the correct gear it's a sure sign there's something wrong. With a manual transmission, you may notice after shifting into a gear that the car's engine will rev up, but the car won't be moving as quickly as the engine is running. In this case, a worn-out clutch or more serious transmission problem may be occurring.
Automatic transmissions have the same lack-of-response problem, but you will usually see the issue while engaging "Park" or "Drive." If your transmission hesitates to go into either one, then it's most likely an issue with the transmission.

Check Engine Light
The check engine light can be a great early indicator that something is starting to go wrong with your transmission. The check engine light can come on for any number of reasons not related to your transmission as well, but don't overlook this clear warning sign.
If you want to know if your check engine light is telling you about a transmission problem, you can purchase a diagnostic scan tool that you plug into your car underneath the driver's side of the instrument panel. The scan tool will display a code that corresponds to the area of the vehicle causing the fault.

If you or a co-worker is in an accident and you need replacement parts for your medium or heavy duty commercial truck, call us at (803) 564-3228 or (877) 564-6307. If you have any difficulties getting through our phone system, please use our Contact Form or Parts Request Form, or email sales@busbeetruckparts.com.

We have hundreds of Salvaged Medium Duty Trucks and Commercial Box Trucks for Parts including: Isuzu, Mitsubishi Fuso, UD, and GMC. With thousands of parts, including our most popular Isuzu NPR Truck Parts, we should have any part that you need in stock. Our sales professionals will be glad to assist you.  We are located at 4107 Festival Trail Rd, Wagener, SC 29164.


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#1 Reason For A Slip In A Standard Transmission

Because a standard transmission uses a driver-operated clutch engaged and disengaged by a foot pedal, and a gear stick operated by hand, he standard transmission could lose all fluid and never slip at all, unlike an automatic transmission.  Though, eventually it will lock up while driving down the road, which is worse.

These transmissions are found in trucks like the Isuzu F-series and Mitsubishi Fuso.

If you have a standard transmission that's slipping, the problem is usually in the clutch. There a several different reasons why a clutch would slip but the most common reason is simply that it's worn out. A clutch disc can last anywhere from 20k miles to 200k miles, it all depends on how well you drive a standard transmission.

Related: #1 Reason For A Slip In An Automatic Transmission

Riding your clutch on hills, or just not being very good at using it can cause a lot of wear and tear. Learning on a standard transmission can end up costing you a small fortune if you don't get the hang of it quickly.

If you think your clutch is starting to slip you can try a stall testby putting your car in third gear and starting off like you would normally. Once you let the clutch all the way, the engine should stall, if the clutch is slipping you will know right away because the engine RPM's will rise, the car will slowly start rolling, and you will have a strong, burning smell coming from the engine compartment.
Another common reason why a clutch may slip could be a faulty or damaged pressure plate. The pressure plate works on high tension spring pressure, if for some reason the pressure is not even on the clutch disc, the clutch will start to slip.

If your input shaft seal is leaking gear oil onto the clutch disc, this could also cause a slipping clutch.
Search Our Standard Transmissions

If you or a co-worker is in an accident and you need replacement parts for your medium or heavy duty commercial truck, call us at (803) 564-3228 or (877) 564-6307. If you have any difficulties getting through our phone system, please use our Contact Form or Parts Request Form, or email sales@busbeetruckparts.com.

We have hundreds of Salvaged Medium Duty Trucks and Commercial Box Trucks for Parts including: Isuzu, Mitsubishi Fuso, UD, and GMC. With thousands of parts, including our most popular Isuzu NPR Truck Parts, we should have any part that you need in stock. Our sales professionals will be glad to assist you.  We are located at 4107 Festival Trail Rd, Wagener, SC 29164.

Be sure to Subscribe to the Busbee Blog for more helpful tips and tricks for safe and easy driving. Follow us on Facebook and Twitter, and sign up for our Free Monthly Newsletters.

#1 Reason For A Slip In An Automatic Transmission

An automatic transmission can automatically change gear ratios as the vehicle moves, freeing a driver from having to shift gears manually. These transmissions are found in certain mid-size import trucks including the Isuzu N-Series and Mitsubishi Fuso.

If your automatic transmission is slipping, you will feel it. You will notice that the gears take longer to engage than normal and that's exactly what's happening.

The number one reason why automatic transmissions slip is low fluid.

Related: #1 Reason For A Slip In A Standard Transmission

So the next question is why is your transmission low on fluid? We're going to guess that you have done your regular check ups and your transmission fluid is low because there is a leak. Maybe you've noticed some small puddles where you park your car at night but it never dawned on you that it could be your car leaking.

A transmission has several different seals that hold the fluid in the transmission, most likely your leak has been caused by a failing seal. If you do have a seal that is leaking, and you catch it in time without damaging your transmission, costs could be quite low to repair it. Changing a seal of any kind on an automatic transmission involves removing some type of shaft and sometimes the labor can get intense. At the minimum, you are probably looking at about two hour's labor, and depending on where the leak is located it could cost a lot more.

There are other common causes of a transmission slip that range from poor cleanup to defective parts. Another cause could be that the transmission band is worn out or broken. With this type of problem, you will not only have to deal with the transmission slipping but a multitude of engine troubles, including worn out transmission gears.

Both automatic and manual transmissions uses clutches, and sometimes the clutch can become too thin, causing the transmission to slip.

Search Our Automatic Transmissions

If you or a co-worker is in an accident and you need replacement parts for your medium or heavy duty commercial truck, call us at (803) 564-3228 or (877) 564-6307. If you have any difficulties getting through our phone system, please use our Contact Form or Parts Request Form, or email sales@busbeetruckparts.com.

We have hundreds of Salvaged Medium Duty Trucks and Commercial Box Trucks for Parts including: Isuzu, Mitsubishi Fuso, UD, and GMC. With thousands of parts, including our most popular Isuzu NPR Truck Parts, we should have any part that you need in stock. Our sales professionals will be glad to assist you.  We are located at 4107 Festival Trail Rd, Wagener, SC 29164.


Be sure to Subscribe to the Busbee Blog for more helpful tips and tricks for safe and easy driving. Follow us on Facebook and Twitter, and sign up for our Free Monthly Newsletters.