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MG MGB Technical - MGB rear clunk

After an exhausting weekend trying to remove one stubborn (seized on and adjuster sheared off) rear brake drum on my 69 MGB I am now ready to tackle the rear wheel clunk which from reading past posts could be the diff thrust washer. Am I on the right track here? Or could it be something else before I start pulling the back end apart? The rear wheels when raised and rotated move from 12 o’clock to 2 o’clock and then you get a clunk. I just wanted someone else’s experience and advice here. Regards AG
Albert Gate

I would be ruling out the propshaft UJ's first by getting a big screwdriver in there & checking for play.
G Britnell

Do you have wire wheels? More of a click than a clunk, but they can be noisy when you pull away if not tight or the splines are worn.
David JM

I will check the prop shaft UJ's when I get home from work, could be that. My splines are good; with the car jacked up & wire wheels removed I rotate the half shaft by hand and still get the unrestricted movement and then something engages and then a clunk. If it is a thrust washer can I do the job with the fuel tank in-place? I spent allot of time refitting it after a re-furb and don't really want to take it out again.
Albert Gate

Doing you own, partial, re-furb of the dif is quite simple with the axle in place. As a minimum their are 4 washers (2 bronze 2 fibre)to replace, the pinion shaft and a roll pin. If you can get them pinion gears, and more difficult to get, are the half shaft gears.
Allan Reeling

I get the same sort of clunk as I take up drive and release, I have always thought it is just wear in the drive train. Have not checked the propshaft as just by looking at it and feeling is not enough, yes probably need to get a good long screwdriver or bar. With the wheels off the ground there does seem to be a large segment of the discribed circle which is slack before drive, as it were 'connects'. Funny, you seem to get used to it and modify the driving tecnique to compensate for the wear, anybody else find this? MIke
J.M. Doust

My 77 Roadster has the clunk and its deffo the diff. I have the thrust washers but have not attempted the job yet. I think I am right that you need to remove one halfshaft but yes the job can be done in situ and you dont have to remove the tank.
PC Holdsworth

Albert, check the dif backlash by applying handbrake and turning the nose flange. Also check the hubs on the half shafts. The splines can wear especially if the securing nut wasn't properly torqued up when the seals/backplate were played with. This is at least 150ft/lbs?
Allan Reeling

Support the body to allow the axle to hang down to give you more access.
PaulH Solihull

All theories about the 'clunk from rear' says it's the diff.

My '74 Jubilee (Car no 730/750) has the same clunk, and new washers have been ordered.

Having seen a couple on youtube-videos on the subject, as well as reading a lot about it, have convinced me it's a DIY job, done in a few hours.

Björn-Anders Haverstad

This thread was discussed between 23/05/2011 and 31/05/2011

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