One of the most common automatic transmission problems is shifting hard. If your Cadillac DeVille has a hard shifting transmission is not only can be uncomfortable to drive, it can be a sign of some serious problems.
Transmission Shifting Hard Diagnosis: Cadillac DeVille
Here is a list of practical things that most people can do when their transmission is shifting too hard.
1. Check The Fluid Level
A transmission with fluid that’s low, will not operate normally. That’s because automatic transmission fluid is a hydraulic fluid that transfers the energy from the engine to the rear wheels. Without it, your DeVille just can’t go.
More often than not, low fluid will cause a transmission to slip, which creates softer shifts. When it finally does grab, it can feel like a harder shift. It is possible for some transmissions to shift harder when they are low, but not too low, even if it is not slipping at all.
Look under where you park the vehicle and check to see if there is any fluid down there. That is an obvious sign there is something wrong.
2. Check the Fluid For Signs of Wear
So, the fluid level checked out. Now it’s time to see if the fluid itself may be causing your vehicle to shift too hard. Transmission fluid that is worn out can cause harsh gear shifts and damage the synchros and clutches.
Checking your fluid can tell you a whole lot about what is going on inside of the transmission. Here’s a good article on using transmission fluid color to help determine what is going on in the transmission. If it is really dark, burnt, or past the time that the manufacturer wants it changed, changing the fluid may stop the transmission from shifting hard.
3. Keep Your Nose Open
Even if you don’t see the transmission fluid, you can still smell that something is wrong with it. Burning transmission fluid stinks. It doesn’t smell like burning oil. It has more of the smell of burning rubber.
Beware that if you smell burning transmission fluid because it is leaking onto something like the exhaust, it is MUCH MORE FLAMMABLE than motor oil.
When it is getting burnt inside the transmission case, it’s usually due to it being too old, the level being too low, or your DeVille having done something that it was never designed to do (such as carrying too much weight).
4. Keep an Ear Open
Listen to your DeVille as you accelerate and decelerate. A transmission that is going bad will often make a whining noise. Listen for anything out of the ordinary. You already know that your transmission is shifting too hard, so it’s more than likely if you hear any strange noise they are related
This would indicate an internal transmission issue, which is item #6 on this list.
5. Check Engine Light
If your DeVille is shifting hard, and you get the check engine light, there may be a diagnostic trouble code stored in the memory. If the code is transmission related, you can use the information to help you diagnose why the transmission is shifting hard. It’s a heck of a lot better than being in the dark.
6. Internal Transmission Issue
Repairing an automatic transmission is one of the most difficult mechanical projects that there is. If you have used the practical advice above and gotten nowhere, then it may be time to have a professional take a look at your vehicle. They may find internal damage to the transmission, or the transmission controller.
Rebuilding or replacing the transmission in a vehicle is one of the most expensive auto repair projects that there is. You can save money by taking it in when it’s still shifting hard, before the transmission fails altogether.
7. Clogged Filter
If the transmission filter is clogged it can cause the operating pressure inside the case to get too low. This will change the shift quality.
Conclusion: DeVille Shifting Hard
If your transmission is shifting hard, the first thing that you are going to want to do is check the trouble codes if you have a check engine light. If you do not have a check engine light, make sure that the fluid looks good and that it is not burnt.
We recommend your DeVille to a transmission repair shop as soon as you have determined that it is most likely an internal transmission issue. The longer that you drive when it is not shifting right, the more long term damage that you will do.