Some humming goin on

[Rockinlittle325i]

so on the way back from the bech my car starts humming, kind of vibrating the body, whenever I have it in gear at 3-4k revs
it seems like its coming from the rear too....
any ideas?



also she died at a stop light, but restarted later, and has lost power but I'm sort of sure its the fuel pump (a result of the 6 hours driven)

[bimmer_E30]

Diff is going?

[bataangpinoy]

for that vibration, check the guibo bolts, trans mount bolts etc. if they are loose or if you are down one shit will shake

[Rockinlittle325i]

I just got back from a test drive, it is only under throttle and letting off at high speeds in 3rd 4th and 5th gear,
some times I get it when I put it in neutral at those speeds (55-80 mph) but at 90+ it's as smooth as glass

(stupid question: what are guibo bolts?)

[Rockinlittle325i]

how do I test if the diff is going?

[catchuk]

guibo bolts, guibo is the rubber between the transmission and the driveshaft.

It may be a bad guibo, or center bearing on the driveshaft.

[Rockinlittle325i]

would any of those things be affected by only torque?

[blunttech]

would any of those things be affected by only torque?

yes like said, its most likely a bad guibo or center bearing. if you find one is bad replace them both while its apart and dont buy that indian world pac shit. if you buy world pac be certain youre getting febi or the like

[M-technik-3]

Check fluid levels as well. Lack of lubricants make a lot of noise.

[Rockinlittle325i]

I'll check the fluids tomorrow

how would I know if any of those are bad? visually?

[M-technik-3]

You need to open the diff and transmission filler caps to check them. Stick a finger in and feel for apparent fluid if none in immediately below hole, it's leaking.

Are the cases wet? differential and transmission? have you checked the drive shaft yet?