Diff drain bolt!
Discussion
Don't bother, get an oil sucker and suck it out of the fill hole. Works a treat.
https://cpc.farnell.com/clarke-international/cht61...
https://cpc.farnell.com/clarke-international/cht61...
I am a big believer in Oil Extractors, I have a Pela 650 that I use for every oil change, and also for removing coolant
There's a copy of the Pela on eBay for just £27
https://www.ebay.co.uk/itm/113665277396
However, I think it could be quite difficult to get the extractor tube to the bottom of the diff, not least because the fill hole is horizontal
So I suggest you persevere with the drain bolt
It's unlikely any bolt will resist Mr Cerbera's method, just make sure you use a really good ring spanner
There's a copy of the Pela on eBay for just £27
https://www.ebay.co.uk/itm/113665277396
However, I think it could be quite difficult to get the extractor tube to the bottom of the diff, not least because the fill hole is horizontal
So I suggest you persevere with the drain bolt
It's unlikely any bolt will resist Mr Cerbera's method, just make sure you use a really good ring spanner
Bolt is neither 12mm or 13mm - 1/2 inch!
Got a socket, wrench, extension bar + jack = didn’t work! My wrench just bust instead! Looks like a ring spanner is next.
No lidl here I’m afraid, just got Aldi. Will an oil sucker really work as I’m not sure the depths of the diff can be really accessed.
Using Castrol 80w 90 - presuming that is good stuff?
Got a socket, wrench, extension bar + jack = didn’t work! My wrench just bust instead! Looks like a ring spanner is next.
No lidl here I’m afraid, just got Aldi. Will an oil sucker really work as I’m not sure the depths of the diff can be really accessed.
Using Castrol 80w 90 - presuming that is good stuff?
Wolvesboy said:
Bolt is neither 12mm or 13mm - 1/2 inch!
Got a socket, wrench, extension bar + jack = didn’t work! My wrench just bust instead! Looks like a ring spanner is next.
No lidl here I’m afraid, just got Aldi. Will an oil sucker really work as I’m not sure the depths of the diff can be really accessed.
Using Castrol 80w 90 - presuming that is good stuff?
Needs to be LSD oil! Assuming it is a plate diff.. That temp range sounds like normal diff oil.. Should be 80-140 ish..Got a socket, wrench, extension bar + jack = didn’t work! My wrench just bust instead! Looks like a ring spanner is next.
No lidl here I’m afraid, just got Aldi. Will an oil sucker really work as I’m not sure the depths of the diff can be really accessed.
Using Castrol 80w 90 - presuming that is good stuff?
Be careful what oil you use, i have seen many warnings on here about what can happen if the wrong oil is used in the diff.
I changed my diff oil a while back, heres a link, it might be worth a read. And a picture of the oil i used.
https://www.pistonheads.com/gassing/topic.asp?h=0&...
I changed my diff oil a while back, heres a link, it might be worth a read. And a picture of the oil i used.
https://www.pistonheads.com/gassing/topic.asp?h=0&...
I had to resort to welding a 19mm wheel nut on my BTR diff drain plug to get it out, immediately after the weld and while everything was still hot I put a six sided socket on the nut, I then used a long breaker bar with a length of pipe over it as an extender.
Like this it still took a lot of force to crack the plug free, my guess is BTR used some serious thread lock compound and crammed that drain plug up to a crazy torque too. Its clear BTR didn't want to make oil changes easy, and even more clear most TVR dealerships ignored the oil change intervals.
If your drain plug is so tight it seems impossible to undo, it's highly likely the oil in your diff has never been changed!
Sucking the oil out is a less satisfactory work around in my opinion, as with an engine oil change I far prefer to use the drain method. Sludge is the issue as it tends to sit at the bottom of the diff or sump, this is is why manufacturers fit a drain plug and position it at the lowest point, the reality is you'll never completely suck out all that sludge with a vacuum pump.
When I drained my diff for the first time the car had covered 35,000 miles and it was quite clear from how tight the plug was it had never been changed, quite a bit of nasty thicker emulsified oil came out towards the end of the drain process so I left it a good few hours to fully clear. It's important to understand the diff will make pressure during normal operation which is why it needs the breather, the thing is as the diff cools it will draw moisture from the air through that same breather which over time will emulsify the oil and create sludge.
Diff, engine or gearbox I firmly believe it's well worth the effort getting the drain plug out as it allows for a proper and complete drain, having open filler and drain holes also allows you to complete a flush. I always feel its reassuring to see clean oil coming out of a drain hole before refitting the plug as it's a visual guarantee all the old oil and any sludge has been completely purged from the diff, engine or gearbox.
It's why drain plugs are fitted... and should always be used
Like this it still took a lot of force to crack the plug free, my guess is BTR used some serious thread lock compound and crammed that drain plug up to a crazy torque too. Its clear BTR didn't want to make oil changes easy, and even more clear most TVR dealerships ignored the oil change intervals.
If your drain plug is so tight it seems impossible to undo, it's highly likely the oil in your diff has never been changed!
Sucking the oil out is a less satisfactory work around in my opinion, as with an engine oil change I far prefer to use the drain method. Sludge is the issue as it tends to sit at the bottom of the diff or sump, this is is why manufacturers fit a drain plug and position it at the lowest point, the reality is you'll never completely suck out all that sludge with a vacuum pump.
When I drained my diff for the first time the car had covered 35,000 miles and it was quite clear from how tight the plug was it had never been changed, quite a bit of nasty thicker emulsified oil came out towards the end of the drain process so I left it a good few hours to fully clear. It's important to understand the diff will make pressure during normal operation which is why it needs the breather, the thing is as the diff cools it will draw moisture from the air through that same breather which over time will emulsify the oil and create sludge.
Diff, engine or gearbox I firmly believe it's well worth the effort getting the drain plug out as it allows for a proper and complete drain, having open filler and drain holes also allows you to complete a flush. I always feel its reassuring to see clean oil coming out of a drain hole before refitting the plug as it's a visual guarantee all the old oil and any sludge has been completely purged from the diff, engine or gearbox.
It's why drain plugs are fitted... and should always be used
ChimpOnGas said:
Sucking the oil out is a less satisfactory work around in my opinion, as with an engine oil change I far prefer to use the drain method. Sludge is the issue as it tends to sit at the bottom of the diff or sump, this is is why manufacturers fit a drain plug and position it at the lowest point, the reality is you'll never completely suck out all that sludge with a vacuum pump.
I don't agree, because every time I change the engine oil I inspect the drain plug magnet afterwardsNo more than a few drips of oil is ever left in the sump of any car whose oil I've changed this way
100% with CoG on this, well said Sir.
Professionally speaking, it's an absolute bodge to suck oil, the sort of malarky you'd expect from KrapFit or Halfrauds and their ilk. It should only ever be done as a desperate last resort when all attempts to remove the DRAIN plug (there's a clue there somewhere...) have failed. The only exception is where there is no DRAIN plug, eg those godawful so-called 'Smart'-car pieces-of-sh
te (that's 'smart' as in 'smart' motorways) And boats.
Otherwise, remove the DRAIN plug, and let it all DRAIN out whilst you're getting on with other stuff.
Professionally speaking, it's an absolute bodge to suck oil, the sort of malarky you'd expect from KrapFit or Halfrauds and their ilk. It should only ever be done as a desperate last resort when all attempts to remove the DRAIN plug (there's a clue there somewhere...) have failed. The only exception is where there is no DRAIN plug, eg those godawful so-called 'Smart'-car pieces-of-sh
te (that's 'smart' as in 'smart' motorways) And boats. Otherwise, remove the DRAIN plug, and let it all DRAIN out whilst you're getting on with other stuff.
At least there is a drain plug, too. I've had diffs where there wasn't, you had to unbolt the cover and let it out that way. Did give good access to check and clean it out though.
Bet that saved 50p per diff in production, too, so I suppose someone got brownie points for that decision.
Bet that saved 50p per diff in production, too, so I suppose someone got brownie points for that decision.
Gassing Station | Cerbera | Top of Page | What's New | My Stuff