11 replies to this topic

[Bigtony2285]

Hi guys finally got my recent purchased mini on the road today. I've noticed 1st 2nd and 3rd gear are quite noisy but 4th is fine I didn't noitice it on road test when I bought it but now I've done 80-100 miles today in it I've noticed it. Is this a normal thing or is there bearings that 1 2 and 3 use that could b on there way out ??? Thanks

[cian]

Has it had gearbox work previously?

[sledgehammer]

Layshaft bearing on the way out?

 

1 2 & 3 use the layshaft for gearing

 

reverse is usually a bit noisier anyway 

 

the above is just a wild guess - fingers crossed for something cheaper - easier to get to

 

what state is the oil in ?

 

is the exhaust fowling the underside , exaggerating gear noise or an engine mount / steady , failing / moving 

 

the above may be noticed more in 1 2 3 gear , as the engine moves more in lower gears due to torque reaction

Edited by sledgehammer, 01 May 2017 - 08:25 PM.

[Bigtony2285]

No prevous gearbox work known of. I was thinking layshaft bearings but don't know much about mini boxes. I know like on truck boxes I've worked on, top gear is direct through the the box n don't transfer power through layshaft whilst in that gear. Cause it was a new buy I did do an oil change and the magnet on the bung had hardly any filings on it. If someone is wondering I used a quality 20w50 oil as most people on here recommend

[MacGyver]

Main gearbox double bearing... In 4th there is a 'cleaner' load on it and thus less noise. (4th is right next to the double bearing.)
You need a full strip down if I'm right...Sorry...

Ben

[Bigtony2285]

I thought box rebuild would be the case. Engine and box is coming out this winter to tidy up engine bay so will have to do then cheers

[MacGyver]

Might be a good idea to do some upgrades while you're at it like centre oil pickup.
And have a good look at the differential too, new bearings all round is the best option as it would be a shame to do half of them and have to take it out again next year for the other half.

My brother whished he listened to me, as he rebuilt everything... apart from the gearbox. And his car is immobilised indefinitely now, as he has no time to do it.
Take your time and check everything. 😀

Ben

Edited by MacGyver, 07 May 2017 - 02:31 PM.

[RooBoonix]

Main gearbox double bearing... In 4th there is a 'cleaner' load on it and thus less noise. (4th is right next to the double bearing.)
You need a full strip down if I'm right...Sorry...

Ben

4th is furthest away from double roller, it's closest to the single roller/transfer case end.

Your theory may still be right, or it may even be the single roller. I know the double roller in mine had a scored ball bearing but never made any noise. Replaced it anyway.

[MacGyver]

Main gearbox double bearing... In 4th there is a 'cleaner' load on it and thus less noise. (4th is right next to the double bearing.)
You need a full strip down if I'm right...Sorry...

Ben

4th is furthest away from double roller, it's closest to the single roller/transfer case end.

Your theory may still be right, or it may even be the single roller. I know the double roller in mine had a scored ball bearing but never made any noise. Replaced it anyway.

...Oh, yeah right...
Mine Had the plastic ball cage collapse in the double bearing, and less load in 4th so less noise.
Apparently the cage disintegrating is a common problem on later models, or so I've been told...
No matter what it is, if it sounds like it's grinding salt, it needs checking. 😀

[RooBoonix]

Main gearbox double bearing... In 4th there is a 'cleaner' load on it and thus less noise. (4th is right next to the double bearing.)
You need a full strip down if I'm right...Sorry...

Ben

4th is furthest away from double roller, it's closest to the single roller/transfer case end.

Your theory may still be right, or it may even be the single roller. I know the double roller in mine had a scored ball bearing but never made any noise. Replaced it anyway.

...Oh, yeah right...
Mine Had the plastic ball cage collapse in the double bearing, and less load in 4th so less noise.
Apparently the cage disintegrating is a common problem on later models, or so I've been told...
No matter what it is, if it sounds like it's grinding salt, it needs checking. 😀

Hadn't heard that, good to know.

Just make sure any replacement bearings are of the best quality available, preferably OEM, I think it's RHP for the double roller. Any doubts, contact guessworks on the forum he'll he able to sort you out.

[Bigtony2285]

Cheers for all the help guys

[Guess-Works.com]

To an extent all the above is true, but in essence the bearings, which ever one, two or three of them, are worn... With the double roller collapsing the gearbox can lock at low speed < less than walking pace, but as mentioned above once the mainshaft is spinning is has less tendancy do move... The laygear bearings are probably making the noise..

Long and short.... Engine out, gearbox off.