How to undo the rear diff plug?

[gavgavgav]

I've the GKN diff that I want to change the oil on, same as the photo below;



(Pic borrowed from http://www.pistonheads.com/gassing/topic.asp?t=948...

What is the trick to getting a tool to the plug/ what tool works? It seems to be a 1/2 inch plug but it is a bugger to get to, and the chassis/ body makes it tricky to get a socket driver into it.

[TVR500Morgan]

Last one I did I used a 3/8 breaker bar with no extention. It really depends what position the plug is with regards to how difficult it will be. As soon as you've broken the seal jiggle the bar out and do it by hand or you won't get the bar or plug out. Hope this helps !

[TVR500Morgan]

Just realised you said it was 1/2 in. Same applies just use a 1/2in. Breaker without any extention. I'm sure I used a 3/8 breaker on the last one I did though.

[Barreti]

I used every extention bar I had to get my air impact wrench to it in the wheel arch.

It took ages to undo and eventually let go with a hell of a bang.

[gavgavgav]

Barreti said:

I used every extention bar I had to get my air impact wrench to it in the wheel arch.

It took ages to undo and eventually let go with a hell of a bang.

I'm not sure you are referring to the same plug? You would need to be a magician to get a impact wrench on this one (it faces the rear of the car not the side). Note there are 2 kinds of GKN arrangements.

[DarkMatter]

Barreti said:

I used every extention bar I had to get my air impact wrench to it in the wheel arch.

It took ages to undo and eventually let go with a hell of a bang.

Was yours a GKN diff, with the filler hole at the back?

I've done it two ways, and they are both fiddly.

The first time I used a piece of 1/2" square steel bar of sufficient length to protrude just beyond the chassis cross member. This is where my memory is a bit vague, I can't remember whether I turned it with an long adjustable wrench or by usinf a suitably sized socket % wrench.

The second time (when I was only tightening it) I used one of those special sump plug 'sockets' and found that I could just get an open ended spanner to it by kind of reaching up the side of the diff.

[gavgavgav]

DarkMatter said:

Was yours a GKN diff, with the filler hole at the back?

I've done it two ways, and they are both fiddly.

The first time I used a piece of 1/2" square steel bar of sufficient length to protrude just beyond the chassis cross member. This is where my memory is a bit vague, I can't remember whether I turned it with an long adjustable wrench or by usinf a suitably sized socket % wrench.

The second time (when I was only tightening it) I used one of those special sump plug 'sockets' and found that I could just get an open ended spanner to it by kind of reaching up the side of the diff.

Thanks for that, have ebay'ed a suitable length of bar to try out.