G'day,
My name is joe a newbie to the site.

I have an 83 998 classic look Mini with a dreadful rumbling, clunking expensive sounding noise from under the front left of the car at any speed or load.

I say any speed but read less than 80k as I reckon that would just about be the cars top speed, the diff ratio is really low so that will have to sorted one day.

I have replaced everything in the drive line, wheel bearings, upper/lower ball joints, tie rod ends but not the inner and outer CVs which feel fine.

So that leaves the diff bearings, my question is can they be replaced with the engine/trans in situ, I guess the answer will be, yes, but with great difficulty,
joe.

I don't think you could do them without taking out the engine (at least without great difficulty). You've got to get the driveshafts off, diff housing off and remove the diff to replace the bearings. You've got to re-shim the bearings too when you re-install them.

If you have a clunking noise it could well be the diff pin and/or planet gears are worn. The CV joints might feel ok under no load, but they could be worn out enough to clunk under load.

It could also be something in the front suspension - cone, knuckle joint, tie bar, top/bottom arm...

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G'day timmy202,
Thank's for your reply, all the suspension arm pivots are kosher as are the upright bits, you could well be correct about the feel of the cv's not being enough to discount them from the noise sourc, the outers are cheap enough so are on the replacement list.
I checked the drive shafts inners for movement while in situ and found that left side had too much play for me so I took the shafts out, that's when I discovered that the left side diff output spline was pretty sloppy hence my suspicion about the bearings.
It appears that the whole lot will have to come out, at least I will be able to fix the ratio a bit,
Joe.

Was it the Pot that was sloppy? If its that your talking about that then you are likely to need the side cover bush done.

A clunk could be coming from the subframe mounting bolts. I would check all of them as well as your engine mounts.

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1963 Morris 850 Smoke Grey
1963 Morris 850 Shadow Blue
1965 Morris Mini Smooth Van
1966 Morris Mini Van
1969 Morris Mini Deluxe Resto
5/72 Clubman Gt

Have you tried running on hoist to determine where the noise is coming from. I would be more of the opinion that worn diff bearings would cause a whine rather than rumble. I'd be doing a bit more investigating before ripping engine out.

My guess is the inner pot joint. Or the muffler bearings.

Muffler bearings sound hard to replace

_________________
1963 Morris 850 Smoke Grey
1963 Morris 850 Shadow Blue
1965 Morris Mini Smooth Van
1966 Morris Mini Van
1969 Morris Mini Deluxe Resto
5/72 Clubman Gt

If you lubricate the blinkers to much you wont hear them flashing. Make sure you follow the directions on the back!

_________________
1963 Morris 850 Smoke Grey
1963 Morris 850 Shadow Blue
1965 Morris Mini Smooth Van
1966 Morris Mini Van
1969 Morris Mini Deluxe Resto
5/72 Clubman Gt

G'day,
and thanks very much for your replies.

The first thing I did was jack up the car and check drive shafts for up/down movement and exhaust system ( I thought it might be bearing, pun intended, against the body, but no)

The left side inner had quite a bit of slop at the inner CV and I was hoping for it to be crook but no, it is in the shaft coming out of the diff.

Whacking it up and running is a good suggestion, pity most of the front is on the floor, hmmm,
joe.

follow the DIRECTIONS, does it INDICATE how much to use?

Haha. Nice one

_________________
1963 Morris 850 Smoke Grey
1963 Morris 850 Shadow Blue
1965 Morris Mini Smooth Van
1966 Morris Mini Van
1969 Morris Mini Deluxe Resto
5/72 Clubman Gt

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'72 Clubman Van - 1022cc, 295 head, 731 cam - Daily Driver
'69 Morris 1100 S - Dinged by a bus, in shed under repair
'64 Morris 1100 - Early 1100, long term project

G'day,
I sprayed the area round my computer with Bullsh*t Repellent last night and have the can and a long handle shovel for severe cases handy so here goes again.

Hey I thought about the left side diff housing and remember a bush replacement being mentioned, I guess it is pressed into the bolt in/on diff housing side ( anyone got a better description than that) where are they available? Also if someone has an inner can handy could you run a set of callipers over the diff input section please, mine looks WELL polished and could be down a bit.
The sub frame mounts were also mentioned, any experience of before and after front end noise would be appreciated, any ideas about where can I get a couple of front mounts and about how much do they cost?
see you later Joe.

Try reading through some old threads with similar issues to yours.

viewtopic.php?f=2&t=88562&hilit=front+end+noise

I will have a look later at some pot joints for you a measure them.
Minikingdom online or Karcraft would have the bushes you are after.

_________________
1963 Morris 850 Smoke Grey
1963 Morris 850 Shadow Blue
1965 Morris Mini Smooth Van
1966 Morris Mini Van
1969 Morris Mini Deluxe Resto
5/72 Clubman Gt