MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Cleaning out the rear axle

I've just treated myself to a new tran-x LSD. :)) Before I start the swap from my standard open diff, I was wondering if there's anything I can do to clean out the axle casing?

I've never broken a half shaft or the standard diff, so I haven't put any shrapnel in there, but I don't know the long term history, and I'd like to protect my investment. I don't want to remove the axle from the car.

Mark

M Crossley

I don't think you need to do anything special. You may want to check the bearings and oil seals in the rear hubs. Sometimes the large locking nut in the centre comes loose so another check there. Also check the expansion valve on the axle casing is working OK

I just washed my diff casing out with a suitable solvent and made sure it was all dry.

With the car up in the air its also a good idea to go over all the rear suspension and make sure its all nice and tight and the bushes are in good order.
Bob Beaumont

Ta Bob,
Good point. I've recently replaced the hub bearings and wheel studs breather etc. The axle fixings/polybushes/RTL are all good. I went over everything recently having found that the bodywork is closer to one wheel than the other.(I believe they're all like that sir! L/H arch closer than R/H)
The diff assembly is a new build, so I don't need to disturb that, I just thought that there might be a way of cleaning the axle casing, so any old muck wouldn't get to contaminate my shiny new CWP/bearings/LSD.

At present I'm thinking of bottle brushes and petrol.

Mk
M Crossley

All sounds good. I wiped out as much oil as I could and used Brake cleaner to wash out the casing as it dried quickly. I prefer to use brake cleaner for cleaning jobs and buying in 5 litre containers is reasonably ecoonomical
Bob Beaumont

Some recommended to fill the axle with paraffin then jack the car up start it and put it in gear to get the back wheels turning and to stir up the paraffin. Stop the car and drain.

If you have recently done an oil change when changing your hub bearings, the fresh oil will probably have done a reasonable job of "washing" the internals.

Malcolm
Malcolm Le Chevalier

Mark,

What oil has been recommended for the Tran-X LSD?

Using a straight SAE90 LSD oil can cause an irritating clicking from the diff when turning at low speeds.

Using Castrol Syntrax/SAF-XJ 75W-140, which was developed for BMW's LSD's, eliminates the clicking.

Richard
Richard Wale

Malcolm

You're probably right about the oil changes. I've done a few just recently. I'm probably making extra work for myself.
I'll be in touch for some more of your halfshaft gaskets. The ones that came with the diff are the thick ones. Yours did a good job last time.

Richard

I asked the Quaife people. They recommended Millers Oils CRX LS full synthetic LSD oil. The first one I came across was a 75w-90 grade. I ordered it from Opie oils. I've bought it now, so I'll see how it goes, but I'll bear the 75w-140 in mind.

Mark
M Crossley

Cool, when you are ready give me a shout at chevalierclassics@gmail.com rather than buying through eBay.

Cheers,
Malcolm
Malcolm Le Chevalier

midgetbr>
What settings are you using for ramp angle and pre-load?

We fitted our ~14 years ago and it came with a choice of 2 ramp angles - 55
Richard Wale

Malcolm,
You have mail.

Richard,
I'm very much a beginner, having only done one car track day at Anglesey, so my impressions will be very amateurish.
I supplied a spare diff to Heathrow Transmissions and explained that I would like to drive to track days, play, and drive home. They ordered the lsd from Quaife and it came marked 45/90 and lightweight. Apparantly there's also an ultra lightweight option, but that's for things like Westfields.
I'm running Frontline front and rear, and one of their RTL setups. The rear springs are saggy standard. The fronts are 340lb and the arb is 11/16". 165/70x13 uniroyals.
With an open diff it seemed to steer quite nicely and I could gain on the MX5's in the corners.
The diff is sat on my bench taunting me at the moment. Daughter number one gets married in a fortnight, so I might not be playing out for a bit.
I'll report back soon.

Mark
M Crossley

Mark,

Sounds like the same settings - should work very well.

Good luck with the wedding using wedding cars sevenoaks!

Richard
Richard Wale

Very interested to read all this as finally I have the spare cash to be fitting a lsd so this proves all very relevant, but...

Can i ask why you went for the tranx? I use a tranx in one of my other cars and its very good so im not disparaging of it, but, the 3j from magic midget at 900 with halfshafts seems to be the best deal i can find for what is a very similar diff? Or do you know something I dont?

(The evolution lsd from minispares is even cheaper but I cant find anyone who has any experience of using one??)

If anyone can give me a recommendation or experience on any of these diffs please say as im about to place an order for a light preload 40/90 3j this week...

Sorry for thread hi jack.

(Car is 1293 ~90bhp fast road and autotest)
C Mason

When I bought ours, the choice was either the Quaife ATB or Tran-X plate type LSD. Since the ATB unit only works when both wheels have some traction, and the problem was the RH side of the axle lifting under torque reaction, the only real choice was the Tran-X.

It has done ~50,000 miles and as part of a recent rear axle rebuild, nothing to do with the LSD, I stripped it and found very little wear, so very pleased.

Now the 3j and EVO have come along and look very similar to the Tran-X - are they 'spin-offs' from the original Tran-X company?

Definitely get the EN40 halfshafts - I broke a 'toughened' one almost immediately after fitting the LSD.

Richard
Richard Wale

Yes I used to have a quaiffe atb in another car and never got on with it.

I noticed magic midget sell "en40b" and "competition" halfshafts and wondered what the difference was...

But yes absolutly understand that the extra strain given by a lsd will overload a standard shaft very quickly.
C Mason

My first port of call was to Kim at Magic Midget, but unfortunately he had no stock of the 3J or half shafts. I got Peter May shafts.
Heathrow Tranmissions advertised the 3J ex stock, so I sent my spare diff assembly. In the end they couldn't get a reliable date for when they'd receive the 3J with suitable settings, so they offered Tran-X with a proper lead time. They built my diff with new bearings, crown wheel and pinion etc and of course the new lsd. All I have to do is pull the new half shafts again, disconnect the prop and swap units.
I had intended having a go fitting the lsd myself, I've done bike final drive assemblies, but in the end I bottled it. I liked the idea of new CWP and bearings, and there were too many things to get wrong with expensive components. There'd also be a nagging doubt in the back of my mind that I hadn't tightened everything up!

I decided against the ATB style. I was put off by the lack of traction if a wheel lifts. I must admit that the low maintainance aspect of the ATB does have its attraction.

Ive not fitted the unit yet, life has intervened, but I'll report back when I'm up and running.
Mark
M Crossley

This thread was discussed between 04/08/2016 and 07/08/2016

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.