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Question:  2002 Toyota Corolla, miles: 89,000 I was told by some service person that it is recommended to change the transmission fluid completely at 30,000 and the same for the fluid in the radiator. This does not sound correct. The transmission fluid has only slight color change and the coolant had little or no color change.

Answer: Check your owner’s manual for the recommended service schedule. These schedules are only guides, however. You should be aware, service intervals very depending on driving conditions and habits. Depending on where you live, 30,000 may not be unreasonable. Color change is a criteria but it must be viewed together with chemical condition.

Question: 2001 GMC 1500 mileage: 101,000. The transmission in the "GMC" seems to be operating correctly but each week when the fluid is checked a pint or so of fluid must be added. There is no evidence of a leak at the transmission pan or anywhere else on the case. The transfer case is also dry. If we park the vehicle on clean paper to detect a leak, there are no drops of oil present even after a long weekend. The engine seems to be running clean with no signs of fouling or blue-black smoke. Where can the transmission fluid be going?

Answer:  If the outside of the transmission is completely dry, the only other place it can leak is into the transfer case. If this is the case, the seal in between the two has failed.

Question: 1999 Isuzu Rodeo, mileage: 50,000. I would like to change the automatic transmission fluid in my vehicle (I am familiar with the procedure on older vehicles) but on my Isuzu the transmission is a sealed unit. It has an overfill and drain plug. I drained approximately 3 quarts and filled it with about the same amount through the overfill hole so the best I was able to do was a partial change (total capacity = 9.1qts). I have searched everywhere for information on how to service this type of transmission (4L30-E) to no avail. Regardless of whether or not it is supposed to be serviced at 100,000+ miles I would rather change oil than change a transmission. How do you change the oil on this type of transmission? The service manual I have gives no specifics.

Question: 1999 BMW 325is mileage: 90,000. The automatic transmission was replaced under warranty at approx. 30K miles. I went to replace the fluid and noticed that there is a BMW sticker on the underside of the transmission that says the transmission is equipped with "lifetime ATF" and not to replace the fluid. What do you recommend regarding changing the fluid? If I should replace the fluid, for this particular car at what periodicity do you recommend replacing the fluid and filter and what type of fluid should I use (that is compatible with "lifetime fluid")?

Answer:   Lifetime fluid means you do not change the fluid. This fluid is only available from BMW.

Question: 2003 Toyota 4Runner, mileage: 61,000.   After running an hour or so on a long trip the transmission oil light comes on showing it is overheating.  Pull over and let it idle until cool down, but it will do it again unless speed held under sixty.  Had transmission flushed, but it keeps on happening.  Suggestions for fixing the problem most welcome.

Answer: Check the temp sender for the transmission. It sounds like it has failed and needs replacing to repair problem.

Question: 2001 Ford Explorer, mileage: 65,000.  I am going to change the transmission fluid for the second time in the vehicle.   I had no problems the first time, however I only drained the transmission, not the torque converter.  I looked for a drain plug in the converter but could not find one.  I would like to drain all the fluid this time around.  Any suggestions on how to drain ALL the fluid from both transmission and torque converter?

Question:  2001 Toyota Tacoma 4x4, mileage: 70,000.  Do you check A/T fluid with engine running or off, hot or cold?  The manual says nothing about checking AT fluid.

Answer: Normally the fluid is checked with the engine running in park at operating temperature.  However, your transmission may be “sealed” with no dipstick.

Question: 1999 Ford Windstar, mileage: 103,600.  Hi, I am sure you have heard some doozies.  What do I need to do when I put transmission fluid in my oil?  Did a complete oil change with a flush and a transmission fluid change.  It seamed to run better.  When I stop its slow starting out and something in the back of the van roars, and there is some jerking also.   Please help I am a waiting to hear from you.

Answer:  Your transmission may be low on fluid.  The transmission fluid level should be checked with the engine running and transmission lever in park. 

Question: 2001 Volvo V70 turbo, mileage: 50,000.  Volvo recommended a full AT flush every 20K miles.  Now (850/70 series) they do not call for any changes at all.  Several owners feel that this is because newer technology in the electronically controlled AT units (with lock-up in 3 of the 4 gears) does not harm the fluid as the older AT units did, hence does not need new fluid over the life of the car.  Furthermore, they claim that new fluid could actually be harmful, as the possibility exists that microscopic dirt particles enter the AT and cause damage.   With this as background, my questions are about newer electronic AT units in general, not just the Volvo units in particular: 1) Do newer electronic AT units need periodic fluid changes?  If so, at what interval?  2) Is it better to do a complete flush and fill over a longer duration or a partial drain and top-off over a shorter duration?  (The question arises because a complete flush and fill may be quite difficult to do, while a partial drain and top-off can potentially be done at every oil change.)  3) Have you ever heard of dirt introduced via the dipstick or with fresh fluid destroying a newer AT unit?  Any comments would be greatly appreciated.

Question:  1999 Jeep Grand Cherokee Limit, mileage: 93,887. I recently changed the automatic transmission filter, gasket & fluid. The fluid that I used was the Dextron 2. Now when I check the fluid, the fluid has several air type bubbles. What could be causing the bubbles and what needs to be done to correct the problem? If I check the fluid when the engine isn't running there isn't any.

Answer: Your transmission may be low on fluid. The bubbles may be the result of air and fluid being sucked up into the filter and pump. Check the fluid level first thing in the morning after the bubbles have settled down over night.

Question: 2001 Mercedes Benz C260 mileage: 90,000. Want to change transmission filter and pan gasket. Because of mileage and not sure when and if prior owner changed fluid, I am afraid to have fluid replaced. Present fluid clear and unburned. Should I chance or will someone just change filter and gasket?

Answer: Change the transmission filter and gasket and at the same time replace the fluid in the pan. With the transmission pan down, inspect for metallic particles. A slight amount is normal.

Question: 2004 Ford Freestar, miles: 78,000 . Recently in the morning after reversing the car out of our driveway and slipping into drive the transmission will not engage for a few seconds. Upon engagement, it drives fine all day long. Is this a band adjustment, or a symptom of worse trouble on the way? If this is a band adjustment, what is the band adjustment procedure and specifications I should use? Thanks in advance for our help. P.S. It has been a few years since I turned wrenches at repair shop!

Answer: A low fluid level in the transmission may cause the problem you describe. Check for external leaks. Also, you might have a problem in the seal for the torque converter.

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