What the transmission does
The transmission is the part that sends engine power to the wheels. It changes gears as you speed up and slow down. Inside are clutch packs, seals, valves and a small computer that runs the show.
When something in there goes wrong, you feel it right away. The car slips, shifts hard, or gets stuck in one gear. The good news is that a scary symptom does not always mean a big repair.
First, make sure it is really the transmission
Many so called transmission problems are something smaller. Low fluid can cause slipping. A leaking pan gasket can drain the fluid. A bad sensor can cause hard shifts.
On many BMW, Mercedes-Benz and Audi cars, the valve body is a common failure. The valve body is the part that routes fluid to change gears. On some cars it comes with its own computer. Replacing that one part can fix the car.
At Athens Import Auto Repair, we test before we decide anything. We scan the car with the right tool for the brand. We check the fluid. We drive it. Then we tell you what it really needs.
When a repair is the right call
A repair makes sense when one part has failed and the rest of the unit is still healthy. We fix or replace that one part, refill the unit with the right fluid, and road test it.
Many BMW, Mercedes-Benz and Lexus cars fit this picture. Their transmissions are well built, and the parts that fail most often are easy to reach. A repair like this can give you many more years of smooth driving.
- One part failed, like a valve body, a solenoid or a seal.
- The fluid is not burnt and there is no metal in it.
- The car shifted fine until one day it did not.
- The engine, body and frame are in good shape.
- You like the car and plan to keep it.
When a replacement is the right call
Sometimes the damage runs all the way through the unit. Burnt fluid, metal in the pan, or worn clutch packs point to that. At that point a repair would only be a patch. A quality replacement unit is the honest fix.
We do not rebuild transmissions. A rebuild means taking the unit apart on the bench and putting it back together with new parts inside. We have found that a good replacement unit is faster, and it comes with its own coverage. So when a transmission is too far gone, we install a replacement instead.
One special case is the CVT. A CVT is a transmission that uses a belt instead of gears. Nissan, Subaru and some Honda cars use them. When a CVT fails, it is nearly always replaced as a whole unit.
- The fluid is dark, burnt or full of metal.
- More than one thing inside has failed.
- The car has a CVT that is slipping or shuddering.
- A good replacement unit fits the car and your budget better than a long repair.
The lifetime fluid myth
Many makers call their transmission fluid lifetime fluid. But fluid still wears out. It gets hot and dirty. Worn fluid wears out clutches and valves faster. A fluid service means we drain the old fluid and change the filter if there is one. Then we fill it with the exact fluid your car calls for.
For many imports, a fluid service around every 60,000 miles is a good idea. It is one of the best ways to avoid a big transmission bill later. Buying a used import? Ask for the fluid history, or have us check the car before you buy.
How we can help
Not sure if it is the transmission? Call us and tell us what you feel. Slipping, a delay when you shift into drive, a shudder or a warning light are all clues. We will test your car and give you honest options, repair or replace.
Athens Import Auto Repair is on Winterville Road in Athens, GA, near the airport. Call 706-353-3880 to set up a visit.
Key takeaways
- Repair when one part failed and the rest is healthy.
- Replace when the damage runs through the whole unit.
- We do not rebuild transmissions. We repair or replace them.
- CVTs are nearly always replaced as a unit.
- Lifetime fluid still wears out. Service it around 60,000 miles.
- Test first. Never decide on a guess.
