Series 2 Broke my rear differential

A couple weeks ago I changed the oil in the rear differential. The fill plug was odd I thought, it did not look like something Land Rover would do, so I suspect a previous owner down the line. The plug can be threaded all the way in so it could potentially drop inside the differential. I threaded the plug in most of the way and realized I had better stop. Well yesterday there was road construction and a bump. Not a huge bump but I was going 80km/h and then it sounded like the gearbox cam loose for a couple seconds. 30 minuted later I get to a spot where I can have a look underneath. I see oil under the rear diff. The bolt came half way through the housing plate cover on the diff, so that means the bolt / plug fell in and got slammed around inside there. I had another hour to go to get home. On the way I guess all the oil left the differential and the landy lugged down real hard 15 minutes from home and then started making some grinding noises. I assume I fried a bearing now too. It was night time so I drove at around 10km/h until i got it home. Lots of loud noises mostly grindy gearbox noises. As I watch some videos today, does anyone have any suggestions? Is it easier to remove the axle or can all be done with jack stands? sigh I plan to heat up the plate and bend the metal where the plug came half way through and weld it. I'm assuming i melted a bearing somewhere. 50/50 on if I messed up a gear. Its almost morning where I am, Ill post pictures later.

Edit: Its morning now, you can see in the pictures its going to be nasty. Looks like I have to remove the fuel tank? I wonder if I should just take the axle off.

Thats is a salisbury diff.
The level plugs are tapered, and after time they can wear as people over tighten them so you can wind them all the way in, red hermatite on the threads will hold it in place nicely.

lynall said:

Thats is a salisbury diff.
The level plugs are tapered, and after time they can wear as people over tighten them so you can wind them all the way in, red hermatite on the threads will hold it in place nicely.

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Well, I just finished driving it with the drive train and half shafts removed. Gearbox is fine I think. I have been blowing petrol in with a air tool and then putting in a telescopic magnetic, I have been pulling out tons of metal shavings. Gears look fine but the front where the drivehsaft enters (bearing for pinion gear) has play in it. Going to patch up the cover at friends house and will put back together tomorrow with update. Is this a hard job to get at that bearing?

CakeBandit said:

Well, I just finished driving it with the drive train and half shafts removed. Gearbox is fine I think. I have been blowing petrol in with a air tool and then putting in a telescopic magnetic, I have been pulling out tons of metal shavings. Gears look fine but the front where the drivehsaft enters (bearing for pinion gear) has play in it. Going to patch up the cover at friends house and will put back together tomorrow with update. Is this a hard job to get at that bearing?

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I have never worked on a salisbury, but believe it is diff out to get at the pinion bearing.

lynall said:

I have never worked on a salisbury, but believe it is diff out to get at the pinion bearing.

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This guy seems like solid advice/tutorial.

Going to sleep on it if I want to try and pull it out to get at pinion.

If you have got away with no gear damage lucky.

EDIT: The threads originally would have been tapped into a pressed sleeve formed from the thin cover metal.

This doesn't appear to be there in the photo. The plug may have been over-tightened in the past, which could have split the threaded sleeve. The damaged sleeve may have been removed and a larger hole drilled into the cover in its place.

The plug looks to have only been held on less than one thread by the thickness of the pressed metal cover alone.

The vibration caused it to turn and work its way inside the diff casing.

page 51-2 of workshop manual s3 see Salisbury diff

Webley1991 said:

EDIT: The threads originally would have been tapped into a pressed sleeve formed from the thin cover metal.

This doesn't appear to be there in the photo. The plug may have been over-tightened in the past, which could have split the threaded sleeve. The damaged sleeve may have been removed and a larger hole drilled into the cover in its place.

The plug looks to have only been held on less than one thread by the thickness of the pressed metal cover alone.

The vibration caused it to turn and work its way inside the diff casing.

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I searched for a new plug to buy, and wow, so many reports of this happening to other owners on google search. Must have been 8 or so topics on other land rover forums. What a design flaw. I ordered parts for just about everything except the shims and the internal gears RTC4488. I think those are fine, so after I cleaned out the diff with petrol and let it dry, when I spin the pinion by hand it makes a grinding noise. My son thinks it becuase there is no oil in it. Im going to say the oppisite and they got wrecked (the inner and outer pinion bearings.

I don't have a spreader, thats a bit out of my budget for one job. So if I understand I can take 2 spanners/wrenches, put the closed end of the spanner on one of the studs, so it would be one spanner on each side, and the open end of the spanners I can put together at top and put a bar into the open ends and use the casing for leverage to spread it? Im on the fence if I want to shim it and do the load preload stuff. I have a lot my plate right now.

tottot said:

If you have got away with no gear damage lucky.

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I guess this diff is solid (salisbury). I was reading about how you can beef up this or that, well I would for sure weld a washer to that filler plug. That seems to me to be the weakest link. Kinda glad that the cover is somewhat thin metal and gave way instead of the crown gear.

I removed my Salisbury diff without needing a spreader, you might be lucky if you just give it a go.

Lmao and to think I m going to just fill the diff oil in my Salisbury as a beginner
So to summarise it : The filler plug is that where you fill the oil right? it went into the diff and then bolted out from its inside opening a new hole

Ekenoos said:

Lmao and to think I m going to just fill the diff oil in my Salisbury as a beginner
So to summarise it : The filler plug is that where you fill the oil right? it went into the diff and then bolted out from its inside opening a new hole

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correct, it will thread all the way in. I hit a bump and with most of the weight of the plug inside, it fell in. So just imagine a long solid plug screwed into sheet metal. A quick fix would be to dent the threads at top of plug and only thread the plug in no more than 50%.

question, Im going to get my yearly road worthiness test done today. So I am just about to put the transmission brake drum back on with the rear drive shaft and both half shafts removed. What are the chances I burn up a wheel bearing with not having gear oil in the differential. I know it lubricates the wheel bearings through the axle, i just think that the oil seal by the pinion gear is probably melted, so i don't want a puddle of oil there if they check. I was just going to put cover back on the rear diff. I found a plug from a oil drum I xan silicone to the fill hole while I wait for parts. Then front wheel drive it about 45 minutes there and 45 minutes back. Is this a big risk or should i just fill it up with gear oil and hope it doesn't leak out. If no gears are spinning in the diff maybe fill it up and the seal holds?

I'd suggest if you're going for an annual road worthiness check that you make the repairs and get it road worthy first.

WoodyO said:

I'd suggest if you're going for an annual road worthiness check that you make the repairs and get it road worthy first.

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Its just brakes, lights, emissions test. nobody cares if its front wheel drive here or rear wheel drive. my question was about the bearings. I'm going to buy some gear oil and fill it just to be safe.

Edit: Passed I took the lazy route in the end since im overdue for a win. Did not fill the diif. I remember pushing grease into them a few years back (wheel bearings) then i remembered I had brake trouble which then heated everything cherry red, which then destroyed the seal. I remember gear oil running down the tires. Its just one thing and a domino effect. If i wasn't so stubborn on keeping everything original she would have had disc brakes years ago.

The hubs will still have some oil in them even with diff drained.

Here is a link to a site selling a genuine original cover (price £195).

The photos show what the thread should look like a lot better than it can be explained in words.

https://www.landrovertreasureshop.c...-salisbury-axle-land-rover-series-def-101fwc/

Webley1991 said:

Here is a link to a site selling a genuine original cover (price £195).

The photos show what the thread should look like a lot better than it can be explained in words.

https://www.landrovertreasureshop.c...-salisbury-axle-land-rover-series-def-101fwc/

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Thanks, Found one on fleabay with cork gasket and plug. Shipping and import duties doubles the price for me, but its still cheaper than buying parts for some of these new vehicles that are OEM parts from factory. I was reading about guys running their diff with no oil, and every one had there pinion gear wrecked, they found metal shavings at first. So I am expecting the same when I pull it out, even though it looks ok when looking at a distance with flashlight.

Edit: Oh, I checked your link, I see the thread, mine did not have that, it was like just a plug screwed into sheetmetal thickness. I hope the one I ordered is like that picture.