Worn Diff and how to know what gearbox’s what?

[Rob Mudhouse]

My car is a 1999 1.4 “Atlantic “ estate on a portuguese plate. It’s in fair condition (bodywise at least) due to the salt free roads , but it’s got about 160k miles on it with probably a fair bit of neglected maintenance. 

What I believe it has got is a worn bush or bearing in the diff, as I can grab the inner end of the driveshaft and move it  up and down in the oil seal about a cm or so! 
I’ve yet to see a parts diagram so I’m not quite sure what’s likely to be worn. 
I’ve had the oil out of the gearbox twice in quick succession in September and there was a lot of ground metal on the magnetic sump plug, both times.

So as far as identifying it, what I’ve got is 20CE28 stamped on the box. I’d really like to try to find another low mileage or rebuilt box while I’m in the UK BUT I could use some help finding a compatible replacement.

All the 20CE28’s I’ve found online are actually in Spain or Portugal.

What complicated buying spares so far is when I’ve used the VIN online I’ve been recommended parts that just aren’t the same as in my oily hands; for instance my driveshafts have 22 splines at the diff and 25 at the hub. The VIN apparently says otherwise!

What I’m hoping the wise on this site can tell me is:

Is there a way for me to identify a 22 splined box from codes, or from being fitted to another variant?

Or alternatively is replacing the worn parts in the diff viable for someone decent mechanics skills but only a basic workshop- definitely NOT an engineering set-up!

I’d be changing the clutch while I’m in there too. 
I hope someone can help me out with some useful info
Thanks 
Rob
My VIN for what it’s worth is VF37EKFXT32833677

---

[ekjdm14]

That does sound like one of the diff bearings has collapsed, I'm surprised it even holds oil and manages to drive still! Testament to these tough little 'boxes.

The diff bearings will be taper roller type and inner race will be pressed onto the diff assembly (you could take it to a machine shop when out, outer race sandwiches into the housing where it splits. If you go in that far, take note of the location of any shims.

I would be concerned about any other wear/damage that may have occurred to the ring gear/output gear and the diff housing considering how bad it is, but I think I'd personally pull the diff off the back of the box & inspect all that and then if it looks usable, order up the bearings and seals you'll need.

Be wary about splitting the actual gearbox case by the way, that's a lot more complex than just dropping the diff off the back & very fiddly to get back together as I found out, so if the rest of it is working OK I'd be tempted to leave that side intact despite the metal shavings and just repair the diff.

[Toms306]

The splines are different between the TU engines and the XU engines.

Weak MA box fitted to the TUs! You should be fine with any box from a 1.4 or 1.6, or even a 106/Saxo etc with the same engine.

I had 2 used boxes on one of my 1.4's before it was even 10 years old but they were cheap and easy to find back then. Replacing the diff bearings might be a better option nowadays. It's quite easy to drop the diff alone as mentioned above.

[ekjdm14]

Just a thought, some TU5 cars (our '97 XS for one) have the BE box fitted so be sure it's correct if buying a replacement online. I believe the easy way to tell "on car" is to look at the hub nut. MA cars have a peened over lock nut whereas BE cars have a larger CV joint with a collar and R pin to lock it. (is my understanding anyway, happy to be corrected by those more knowledgeable)

We've got a decent MA here but it's off a 1.4HDi 206 so the ratios wouldn't be great I don't think & it's hydraulic clutch. Having said that, if the diff tooth count is similar I could just pull the diff out (good bearings) and give you the housing as well in case that's been damaged. How to find the tooth count on the ring gear though?

[welshpug]

306 only ever use an MA on a TU.

[ekjdm14]

Oh, that's a strange one then. Guess the larger driveshafts aren't as concrete as I'd always thought? Times like this I wish servicebox hadn't been taken from us...

[Rob Mudhouse]

Thank you very very much guys,I’ve just spotted your replies I appreciate your input.
I will get a chance to sift this info this evening and respond.
Regards
Rob

[Rob Mudhouse]

You guys are really helping me out thank you
I appreciate the reference to servicebox cos I was hoping to put my VIN in to get some more details on the car but is it maybe now only available paid-for?
Yeah the hub nuts on mine are the peened over type.
So... If it’s the case that the 20CE28 stamped  isn’t overly important and I went for any 1.4/1.6 MA box am I risking  ending up with different splines..?
I waded through a lot of listings for driveshafts last year and it seemed there were quite a choice of spline numbers being offered  (I thought it best I count them myself.)
Although ekjdm14 that’s a kind offer I would prefer to accept if you know the number of output splines is 22.
Probably though I really ought to mention the other continuing mystery noise  It just might relate to the wear in the diff or indicate the box is screwed even
For context you should know that my 1.4 lives on a steep hill at the top of a rough as dogs dirt/rock track , so if there’s a noise brewing this is where it’ll find it’s voice!
Taking off on the flat there’s a bit of a  clunk  but taking the car up the track with any of the necessary gusto needed yields a dull THUMP! Loud, low down and probably central
So, I’ve changed everything I can think of: ARB rubber, ARB extensions , RH wishbone arm TRE , RH driveshaft and support  bearing , rebuilt the Front suspension.replaced the RH hub too.

Still this bloody THUMP, which really sounds like an engine part hitting  the body but I’ve changed all the engine /gearbox mounts in the hunt...
COULD that be emanating from the diff wear or gearbox wear?! I can’t believe it, but I haven’t found the cause of it yet either!
Thought I’d better mention it though...

[ekjdm14]

I'll have a look when I get a chance, got to move the engine/box in the next couple of days anyway. I imagine it could cause a thump if the diff bearings were that shot, although still amazed it's still got drive with the play being that bad! Another favourite for thumps on acceleration are the exhaust hitting somewhere along it's run so worth making sure it's aligned well and the rubbers aren't buggered.

[Rob Mudhouse]

I did wonder about that and changed two exhaust rubbers but fair point , I shall replace the rest to get a complete set

[welshpug]

from memory for a 1.4 there will only be 2 choices of driveshaft, one for abs that used the larger wheel bearing off the bigger engined cars, and the non abs small bearing stuff, the inner ends are the same for all ma boxes.

your code is fairly important, as there are a number of different ma gearbox variants, some linkage differences also.

[Rob Mudhouse]

Thanks for that. So by the sounds of it, it would be ideal to retain the box and just to change the diff .
(On that note ekjdm14 I’ve sent you a message)

---

Mine is non ABS

[welshpug]

changing the diff by itself is not a simple process with an MA, its the first part that goes into the casing before everything else, its also pressed on not bolted.

[Rob Mudhouse]

Ah OK , thank you for the advice. So I may in fact need to be looking for another box, as it sounds like I’d need more of an engineering set up than I’ve got available in Portugal.
Like I said ,those 20CE28 gearboxes I’ve seen online are all out of Spain or Portugal with very limited details of mileage