BMW X3, 2004 Automatic transmission shifting issues
 

Hello, It looks like that the shifting of the automatic transmission in BMW X3, 2004 2.5L are kind of delayed. I noticed while I push the gas pedal and speed is accelerating real well to the point when gear supposed to be switched but it does not happen. I have to temporarily, for one sec, reduce the gas acceleration and then it is shifting. As a result, the car drives is on lower gears than it should. The engine RMP is always on a high side. I am wondering what can be done to resolve this issue. Will the change of the transmission oil change this behavior?According to the manual, the oil is lifetime. I am not sure what can be done. Any advice is highly appreciated.

Thank you in advance.

First check is whether the fluid level is correct, as low fluid level can cause shifting problems. Look for obvious signs of fluid leakage around the transmission.

While the fluid can be changed, there are two schools of thought. Replacing fluid adds new fluid that by design has a high level of detergent in it. That can clean out the transmission, and since there isn't anywhere for the residue to go, it can cause problems in the valve body which has lots of small passages and check valves. Transmission failures can be precipated by changing the fluid in a transmission that is otherwise fine, expecially at higher mileage.

Others feel that clean fluid is better than dirty fluid, and that all transmissions that fail after a fluid change were about to fail anyway.

If the fluid level is correct, and the shifting problem is enough to be noticeable, then you can always decide to change the fluid based on not having anything to lose. I would probably do that myself. If a fluid change doesn't have any effect, take it to a transmission specialist for diagnosis. Your dealer doesn't repair transmissions, so you would need to find an independent that you trust.

Great reply! Thank you for doing it. I will check the fluid level. What would be the best fluid I can add?

Look at the tag on the transmission. Get it from your dealer, that is the safest bet, and it won't matter much because you will only be adding a litre or less. It is probably Dexron, but it pays to be safe.

Thank you again. I'll check this out.

I decided to do it by myself. I assume I need to get Infrared thermometer to check the tranny temperature before adding the oil. I'd like to know which one will be OK to use. I found the one for $29 here: Non-Contact Infrared Laser Thermometer. will be this a good choice?

What is the tranny temperature should be on adding the oil?

Thank you again!

The ATF should be changed at intervals of 160.000km or 100.000mls. The revised Maintenance booklet states this.

Back many years ago, there was a software update that slightly alleviated this problem, where 3rd and 4th gear hold gears too long when going up a gradient. Obviously you are out of warranty, but if you are willing to pay, you could ask and see if the dealer still has the EGS update and how much they charge for the service.

Good to know. Thank you!