Bad Gas Mileage? Roaring noise from underneath. 4.8is
 

I am getting a roaring noise from underneath the pass side floor board front. Sounds like anytime I give it a little gas I hear it. Or sometime if im crusing about 60 -70 mph I can hear and feel a vibration. Has anyone ever expericed this with there x5 4.8is. Also my gas mileage is very bad seems like it gets worst.

I get the same thing, funny Don Jacobs can't feel it...... Not sure what it is though. What kind of gas mileage are you getting? I'm getting 14 mpg with about 90% highway. I thought I should get a little better than that myself. Is your X5 still under warranty? Who do you have work on it around here?

gas mileage
 

I get about 14 city and not that better highway. Don jacobs isnt worth a shit. They can never figure anything out. I use a buddy that used to work at Don Jacobs and he is good. He has the Gt1 Machine so he can do alot of what the dealer does. I belive it might be this valetronic thing alot of people are talking about. I hope not though.

Agreed Don Jacobs sucks.. Mine is there now, only because still under CPO. Would like to get the name of your buddy though for future. What is this valvetronic thing? Mine almost sounds like a wheel bearing or something. Same area you speak of though.

try to listen if it is coming from the transfer case.

U know I own 2 BMW a 745 and a x54.8is and before I found my friend I went to don Jacobs and they really pissed me off. They are thieves and all there parts are above the original BMW list price. I order my parts from a BMW dealership in Ohio and I save so much money. I am a dealer to so I get a little discount. If u ever need any parts or after ur Cpo is finished, u need a good reliable mechanic don't hesitate to email me. I can have same quality work done by a professional that has all the tools the BMW has. He is actually has friends over there at BMW and I believe I have heard about ur x5 is it silver?
The valvetronic is where u have random misfires because ur engine is running right which cause the valves not to fire right. It's a big job and it requires alot of parts I read technical service bulletin on it and I can email it to u if u want. The reason I'm not sure if that's what's wrong with mine is because I have no check engine light. I'm getting a really weird noise from the bottom on hard accelerations. But if I drive really smooth it is not noticeable. Also when first turned on in the morning it vibrates really hard for the first ten min or so. Is that the same issues u are having?

I lifted it off of all four wheels put it in drive and Pressed the gas. The transfer case moves around but nothing tO serious. I guess it only does it under pressure. I have a feeling it may be the rear differential since I just put a front differential in. I'm going to drain the fluid and refill to see if it help as for the vibration I think it may be the mass flow air sensor or something in that field . But again no check engine.

Yea, it's silver. What have you heard about it? I bought it from them CPO, even though I really didn't want to because of their service department. But it sat there and I finally got them down on price where my wants over took my needs and concerns. The first month I had it, it was in the shop three times trying to get the pre purchase issues handled. That added up to about three weeks. They finally got it close enough, and I just wanted to drive it, I I hadn't taken it back until last thursday. Still there, but I am driving a 2010 X5 3.5.
Anyway, this time it is in for the transmission slipping from either third to fourth or fouth to fifth, I can't tell which gear it shifts so much and doesn't seem to do it when shifting manually. And, I tilted open the roof and then it wouldn't close back down. But the roaring has been there and is one of the issues they still have yet to diagnosis. I was kind of thinking mine sounded like a wheel bearing or the transfer case, but it may be transmission related. How did you check your transfer case?

Hey Collie sorry to hear of the misfortune, the positive in all of this is it's CPO. To chime in though I think I came out to look at that one. I got a flakey feeling from them over at Don Jacobs as well. Glad you where able to talk them down because they weren't having it when I went in... Was the rear driver side door inoperable when you got it? If so I think it's the same one I looked at. NICE X though, and shit free repairs. :)

Yep, that's the one. I went out and looked at it when they first put it online at like 34-35k. I offered then 31 on the road, they said no way so I told the salesman alright I'll just let it sit. So three months later it was still there and I had that itchy back pocket feeling again and went back and offered them 26, told them they should have taken the 31 months ago. That's when they door carrier broke and they put it in the shop to fix it. After about 2 weeks of the salesman calling back to try to get more money I threw another 500 to the deal and two days later he called back and said okay you win! But my reservations with Don Jacobs has always been their service department, I had a 2001 4.4 that was in and out of there several times under CPO and they were less than satisfying. I moved to Tampa a few years ago (back in Lex now) and got service at Reeves BMW down there and it was night and day experience. Who else works on yours? What kind of fuel milage are you getting on yours?