Allison Transmission Problems: Top 5 Common Issues

Allison Transmissions are some of the most well-built and reliable brands out there. We rarely see issues with this brand, so it’s going to be a solid choice if you’re looking for a replacement transmission. In fact, our sister company, Breeding Roll Off Service, exclusively uses them for their fleet of roll off trucks.

However, nothing is perfect, and any transmission can develop problems. With Allison transmissions, our technicians have found that the first sign of trouble is your warning light. If you take care of that right away, you shouldn’t have further problems. However, these are the signs you need to watch for when it comes to transmission issues, no matter the brand.

Rough Shifting

One of the prime suspects when your Allison transmission (or any brand) is shifting roughly is the transmission fluid. It may be dirty or running low. Problems could also stem from a faulty sensor, worn gears, or computer issues.

If you’re experiencing rough shifting in your truck, don’t hesitate to book a diagnostic and repair appointment. We’ll get to the root of the problem and get you back on the road in no time.

Slipping Gears

“Slipping” occurs when your truck shifts gears unexpectedly and regardless of the speed you’re going. Technically, this happens when the transmission gears cannot get enough friction to grip. Other causes of slipping could be due to a defective solenoid or torque converter problems. This can be pretty scary, since your control over your vehicle is compromised.

Sometimes, you can fix this yourself pretty easily by getting the transmission hot, and then draining all the fluid and putting fresh fluid in. If that does not solve your slipping problem, you’re going to need a transmission pro – like any one of the Benton Brothers.

Delayed Engagement

If you notice a delay between shifting into gear and your truck moving, you’re experiencing something called delayed engagement. This problem can also indicate issues with your transmission fluid, which should be flushed every 60,000 miles or so. While this is one of the more minor transmission issues, it can become a much bigger problem if ignored.

Overheating

Transmissions get hot while in use, but there’s a point it gets to be too much. If your Allison transmission gets above 220 degrees, the fluid can actually start to burn, harden, or even vanish completely. Eventually, if transmission service is delayed, the transmission will fail.

Overheating is a symptom you’ll want to look out for in the hot summer months, in particular. It’s a reason to have your transmission serviced right away, any time of year.

Leaks and Smells

Lastly, any time you notice leaks or smells coming from your truck, you should identify the source right away for your safety. Sometimes the root cause of the leak or smell can be from an issue with your transmission, but not always.

It’s always wise to get a professional to look at your transmission when you’re experiencing issues with it. Besides the engine, it’s the most crucial component of your truck, and it can be a complicated beast to try to patch up yourself. At M&L Truck Service, we’re happy to take a look and get your transmission back in business.

Meet Heavy-Duty Truck Mechanic, Donald Benton

Donald Benton has worked as a trusted diesel mechanic with M&L Truck Service for 45 years. He says his favorite part of the job is the satisfaction he gets from repairing things that were broken, and getting them back to working order.