Help!! Serious Problem!

[bimmerfan124]

Hello all!! I drive a 95 BMW 540i and a serious problem has recently developed. When I turned the car on and put it into reverse u could hear a grinding/vibrating coming from somewhere down near bottom front of the car. It also does it when in drive to so I haven't driven it at all and I can't take it in till Friday. Some more specifics about the problem.

*In Reverse its a steady deep grumble almost like a exhaust
*In Drive it sounds really bad and slows down the idle to ~550-600RPM when its usually stable at 700.
*Once you put a little pressure on the gas it stops but only while driving forward not in neutral or park u still hear/feel it.
*Can't tell if turning the wheel affects it I think it does slightly seems to be worse when wheel turned to far left or right.
*Car shifts fine still but this does seem like a tranny issue?
*It also grinds worse when the pressure is put on the front end of the car for instance, Braking is bad, parking with the car at a downward slope is bad(UNLESS the car is parked uphill with the front being up it does not grind at all.)

Any ideas I will answer your questions to the best of my knowledge, help me diagnose this!! and thanks in advance to any ideas!

[BOLTEYES-82]

Hi,

is this a an auto box ? if so its probably an oil presure problem there are pressure regulator solenoids on the valve block that can be changed.

do you ever have a TRANS PROGRAM error message ???

[silverturbo]

have you had any recent work done on your car????? I completly agree with BOLTEYES-82. also what about a check engine light has it came on? i know stuip question but.....

[bimmerfan124]

Thank you for the responses..

Yes its an auto box.

No errors or lights on at all.

And no recent work except rear tires.

Any ideas heh :dunno:

[silverturbo]

idle valve?? any kind of vibrations? does the stering wheel shake at all? how loud is the noise? where is the noise sound like its coming from the best way to find that out is start your car up at night so there isnt alot of noise going on around you and open the hood with ur car running lol. also have you check all the fluids?

[texasbeachman]

You may want to check your transmission mounts.

[bimmerfan124]

I don't think its the idle valve because its more than just a rough idle something is restricting something from spinning properly which is causing a rough engine.

Yes a lot of vibration very steady when im in reverse along with a deep steady grumble, but in drive its not steady like it is in reverse but intermittent almost like sometimes it hits and sometimes it doesnt possibly something loose? Steering wheel does shake a little bit and u can def feel the vibration more through it. Noise is very loud inside the car, can't even hear it outside at all except the funny idle.

Need to check tranny fluid because its a sealed tranny I'm gonna take it in and have them check it out.

Tranny mounts do sound like a good idea, I had a mercedes once with the engine mounts bad and it sorta made the same sound as this except I dont think that car did it in reverse.

[BOLTEYES-82]

hi again could even be the torque convereter???

[jimoreno]

I think what you are experiencing is a bad central support bearing (CSB). Does it feel like something is hitting the car's floor right under the parking brake area? If it is, you'll need to drop the exhaust and remove the heat shield to gain access to the driveshaft. Since you'll be down there, check your flex disc (or guibo) and the transmission mounts (for my 530 they were like $9 each at the dealer!).