Broken Diff? Rear grinding/rattling noises.

[islipaway]

Volvo 740 GL 1987 UK

Hello! I am trying to decipher the mysteries held within my recent accident. Some background.

I had my clutch replaced which involved a new clutch, bellhousing and slave parts (all required, long story).

While driving on the motorway the rear left wheel locked up and I did a big skid and ended up on the verge.

I was able to move the car afterwards with some force. While driving forward the passenger side rear brake caliper would occasionally stick and could be seen visibly moving forwards.

Today I removed that caliper, however there is a grinding noise which remains, and the car still holds position as if brake force is being applied. All wheels move freely while in the air.

While jacked up and in neutral spinning the passenger side wheel made the other wheel spin in the opposite direction.
While jacked up and in gear and with the clutch engaged the passenger side wheel spins forward and the drivers side wheel can be stopped by hand or turned backwards.

In neutral the the car holds position as if left in gear. I always put this down to the caliper binding, however there is now no caliper on that side and the other wheel spins freely.

Does any of this ring alarm bells?

Thank you for your time.

[islipaway]

[YOUTUBE]www.youtube.com/watch?v=wtxFEwYRGMk[/YOUTUBE]
(video is being processed, so might appear turned 90 degrees, sorry about that).

[Laird Scooby]

Eeeeekkk!!!!!

Watching the video at about 44s onwards, you can see the propshaft and the diff input flange. It might be my eyesight or the camera angle but it looks distinctly like the flange is out of line so is spinning with the front end of the flange off centre.

Have a look, i think you'll see what i mean.

If i'm right, this would suggest internal damage to the diff and may be doing damage to the propshaft and the centre bearing.

It certainly sounds very strange and even mine that has a bit of wear in the diff sounds nothing like that, even with 150mph showing on the speedo!

[islipaway]

Interesting, could that be cause by improper installation of the propshaft when the clutch was replaced? I already strongly suspect the caliper seizing was related to air trapped in the line when the clutch slave was replace. I find it very hard to trust work done by other people.

I will try and get clearer images of that area.

When I crashed I ended up on an embankment, It may have been knocked in that instance also.

As you can see the condition underneath is not the best. Likely this is the end of it!

[mocambique-amazone]

Sorry to see and hear this. The differential is gone for 100% my opinion? The crossshaft inside the differential is broken. Remove the screw at the lowest point, the oil will run out. Remove the rear cover and have a look. You will find broken parts.
You will find a rear axle at the scrap yard or in this forum even cheaper. Maximum 50 pound I think so. The swap is done in!a few hours on the driveway with a jack and on stands. With enough tee or coffee time too.
The video isn't good enough to see anything on my mobile.
Good luck you didn't hit the tree and didn't do a roll-over. Lucky guy.
Regards, Kay

[islipaway]

Yeah,if it had happened like 250m before this I would have gone down a hill, into a river, into a barrier and been wrecked by a truck. Very lucky.

[Laird Scooby]

Interesting comments there from Kay about the axle being 100% FUBAR - looking at where you ended up i'd say if there was a problem before, that finished it up! Wouldn't be surprised to hear that you find broken bits inside the diff though.
Last time i enquired about a secondhand back axle from Lakes, i was quoted about £250, similar everywhere else i've tried. You may be lucky and get one cheaper, i hope you do!

If the propshaft was seriously out of balance and fitted the wrong way on the flange (can only go on two ways, usually everything is balanced together so doesn't usually matter) then that could potentially cause it but i think that's clutching at straws to be fair.

I'd say you probably had a noisy/worn halfshaft bearing for a long time and it suffered catastrophic collapse/failure, resulting in the halfshaft jamming against the axle shaft housing, just bad luck although whoever did the clutch should have noticed something i would think.

That said they may have just done the job, checked what they had done was ok and called it good to go.

For the record, although the clutch and brake share a hydraulic fluid reservoir, the two systems are independent and it would have to be a big bit of air under severe pressure to cause the brake caliper to seize - in other words almost impossible and you'd have a very spongey brake pedal before that happened too.

Out of curiosity, is that silver-green, colour code 403 by any chance? It looks like the same colour as mine, quite a rare colour!

[islipaway]

Yeah! I am quite fond of the colour. I have contacted some breakers on ebay to see what the cost of the diff parts will be. At £250 + I need to restore all the brakes, at least another £250 and then there's an old idle issue that never got fully resolved... reaches a point I can't afford to pursue it. I checked the compression the other day and it seems decent, 160-175 across all cyls, it idles dead level on LPG now but has a bit of a stumble on petrol. I know you're not a million miles away from me, if ends up I need to be rid of it would you be interested in taking it as spares or project? Not looking for money, just don't want to scrap it but can't really keep it where it is and will be moving across country in a few months and you helped me a lot earlier with the idling issue diagnosis.

[Laird Scooby]

PM sent!

[855 tdi]

that's a real shame you hadn't had this up a bit earlier. I just scrapped a 740 that you could of had the whole rear axle off for free.. I didn't want to waste it but I was fed up of it on the drive and needed the space. Ask about and maybe someone on here has a spare axle for a reasonable price?