01 x5 4.4 transmission problem

While I am working on fixing my e36, my mom's 2001 BMW X5 4.4 auto is having an issue with the transmission. My mom is a very light driver and does not tend to ever accelerate heavily. The problem seems to usually be when she is driving and the X5 goes from 3rd to 4th gear, and right around 20-35 miles an hour, but only when it is being driven lightly. It feels kind of like a vibrating/light shaking and hesitating. She has had me drive it to see what I think and it is hard to find this hesitation unless im in that speed range, am on a very slight incline and am driving lightly (which i dont tend to do in the x5). Her mechanic first said it was a cylinoid that needed to be replaced, but now he says it might be a sticky valve. After talking to the BMW dealership in Portland they said most likely we will need to buy a new transmission. But we do not want to do that. Has anyone had this issue or have an idea of whats going on with it? Thanks.

hi ther, you want to try and check the transmission fluid level, i know bmw state that the fluid is meant to last for life but just check the level and top it up with the long life fluid bmw use, your problem sounds like low on fluid, people should be aware of levels in their auto boxes, first sign of slip, check that level and stop expensive trans failure. people get misguided when bmw say it is a lifetime fluid in trans, it is, but over time the volume of oil decreases and NEEDS TO BE TOPPED UP so that the auto box can work properly, simple but very effective, hope this helps

alright thanks i will check this out and let u kno if the problem goes away

i agree with the second option of the mechanic about the sticky valve, sounds reasonable.. and the dealer, they arent real mechanics these days, just electritions mostly, when they cant find the specific problem, they say it is the whole thing.

Having the same issue and YahamaGreg was too...until he had the transmission flushed and refilled...problem solved...I'll be doing the same in the next week or two...I'll report as soon as it's done