Noisy Drivetrain

[Tom86]

I’m trying to fix or at least quieten all the whirling and rumbling noises from the rear of my car. Anyone have any experience with this? What is the first thing I should check? The diff? tailshaft? Wheel bearings?

[Skylar]

Depends what the noise is.

First thing I'd check is gear mesh between crownwheel and pinion for whirling. I noticed the other day that my F-series whirls like hell after the LSD was put in and it didn't when the open centre was in it. It might be the diff bearings as I got new ones put in but I doubt it. My FC has a lot of backlash but it's relatively quiet from gearmesh, just bad engagement noises from kaaz. My T-series used to 'bang' on overrun, not sure of what caused that, probably the entire diff. One sprinter I was driving had real bad rumbling, like a metal drum was being dragged/rolled behind the car. That was diff bearings.

[ke70dave]

yer diffs are interseting things, you really need to get the nose cone (centre/pinion/crownwheel) setup buy a diff shop, setting all the backlash and what not is pretty crutial for the longetivity and noise of the diff.

if someone has been playing with the rear drums sometimes the backingplates can get bent and rub on the drums, thats a pretty annoying sound.

my gearbox whines slightly in 5th gear, but its quiet in the otheres, not sure whats goin on there.

tailshaft shouldnt cause you to much troubles, if the centre bearing is stuffed you would get noise, not sure how you can tell if its stuffed or not. pull it off and give it a spin?

[Tom86]

It just a constant rumbling type noise at any speed. Very hard to pin point where it is coming from exactly. Also, how much backlash is normal? I noticed that when I spin the tailshaft by hand a fair bit of play before the rear wheels start to spin is this normal?

[Skylar]

Tailshafts bang around when you load them up.

My F-series was set up by a diff guy and I'm disappointed by it. None of the other cars/diffs haven't been touched by me.

Whiney 5th is normally a sign of the heat treatment being worn off. My RB20 tranny whines fierce in 5th gear that I sometimes want to shift down to 4th on the freeway. Can't do that coz i got a 4.5 rear end and would rev at ~4k. Boo.

Shouldn't have more than a few degrees of tailshaft movement with handbrake on, I reckon. Anymore than that and you can feel it going on and off throttle.

[H8CHIR6KU]

It just a constant rumbling type noise at any speed. Very hard to pin point where it is coming from exactly. Also, how much backlash is normal? I noticed that when I spin the tailshaft by hand a fair bit of play before the rear wheels start to spin is this normal?

yeah there is a bit of movement which is normal tom. i would check all your oil levels in your gearbox and diff first and maybe change them. a change of oil wont hurt it and if the noise changes then you atleast know where the problem is coming from.

alot of 86 i have been in have really loud wheel bearing noise and when they are bad they can be noisy from any speed. wheel bearings take a heap of abuse esp when the car is thrashed.

i usually find with diffs that they are noisy more around the 60kmh mark and upwards except when they are run dry.