friend need advice.

[yen187]

All,my friend needs some advice for his E46...i dont know as i do not encounter these issues...1) sometimes when gears are changing there is a jerk or when slowing down there is a thud as the gear drops.2) humming sound coming from engine.Any advice on whats happening?this is because no errors are recorded and no error pops up.thanks in advance

 

[wolverine]

Firstly, u need to specify what engine & year model is the car...

In general,
1) try to determine if the jerk & thud feels like from the gearbox or chasis. If the gearbox, which most of the time will record a fault code, are the sensors inside gearbox. Can be replaced easily & cheap too. Also, fresh gearbox fluid with new filter will help a lot.
If it feels like the chasis, hoist the car & check for the front arms bushes, rear subframe bushes, rear differential mounting too.

2) humming sound from engine could be from alternator, belt tensioners, even water pump...

 

[yen187]

sorry for not updating it...

its a E46 320 2.0 6 cyclinder

i think its the gearbox because it only happens when changing of gear (just sat his car)
according to him the gearbox fluid was changed about 20k or 30k km ago...

but how to identify whether it is gearbox or chasis?
he just changed lower arm so i think it should have been checked right? i'm just guessing

 

[anaksarawak]

Where is the car? Check out the list of workshop we always go as listed or mentioned many times in the forum go to seek their views. Remember go to at least 2 workshop including the famous mscope at batu cave

Good luck bro

 

[Iceduke]

All,

my friend needs some advice for his E46...
i dont know as i do not encounter these issues...

1) sometimes when gears are changing there is a jerk or when slowing down there is a thud as the gear drops.
2) humming sound coming from engine.

Any advice on whats happening?
this is because no errors are recorded and no error pops up.

thanks in advance

allow me to give my 2sen...I think this thud is normal for older cars, I have the same as well when the car slows to a stop. The thud is normally heard at the rear. This I attribute to the differential or rear subframe mountings that are past its age. If the sound is from the rear then its the 4 subframe bushes. Its a common wear item on e46s.

Hope this helps.

 

[Alex5522]

Yupe bro Iceduke was right if the "thud" sound came from rear most properly the Rear axle Rubber Mounting was the culprit. Pls..refer my posting on #49 http://www.bmwclubmalaysia.com/forums/showthread.php?43703-Sound-while-going-into-reverse-gear-*THUD*/page5
Hope it's help.