Rear difflock actuator

[clivehorridge]

It should be obvious.

When the diff is locked, the rear wheels rotate at the same speed, so if you do a full-lock turn with it locked, one wheel (normally the inside wheel) will skid and hop.

If you do this, make sure you do it on wet grass, soil or gravel, because on asphalt you create huge forces trying to twist the two shafts at different speeds (wind-up) and something might give.

 

[diggerdave]

Victory!
Since I can't weld I couldn't follow Trevor's slide hammer route, so I though how best to impart torque rather than pulling force, but without using a BFH. So I carved what was left of the back plate into a rectangle with a power hacksaw and a sharp chisel so that I could apply a spanner and twist. It needed a LOT of repeated heat (top tip Andy Lomas - thanks) to break the corrosion and in the end a gentle twist was all that it needed, although I also had the option of using my favourite trick of jacking up the spanner and using the weight of the car to crack it. Photos poor because of lack of daylight, but hopefully give an idea.

It's not quite finished. My actuator is from an 80 front axle and the plug is a different shape (still 5 pins though) and will need to be swapped and the upper stud is out, but still has bits of old actuator welded to it!

Thanks for everyone's help and encouragement. A tough job.

 

[Trevor]

Result, top effort and ingenuity. Well done indeed.

 

[Coops]

Oh wow thats mad! Top marks for completing it.

 

[diggerdave]

Plug swapped, new M8 hole drilled and tapped to accept the guard (my second hand actuator was from an 80's front axle and didn't have a guard), all studs cleaned with appropriate dies, actuator installed, tested and working (solid red light). Phew

 

[Cruiserdude]

Great job and useful to see the pics, thanks for sharing. I still have mine to do at some stage but as yet don't have a replacement. I've considered looking into the ARB air lockers or similar, but imagine they'll be super expensive. Anyone any experience with that type of upgrade?

Cheers,
Mark

 

[BobMurphy]

Dave,
Apologies, I'm a bit late to the party. I have removed three of these for members (as well as doing mine).

I cut off as much as I could, leaving the remains of the alloy body plus what was left of the shaft sticking out of the diff then used a Bosch Hole Saw (20mm) to cut away the alloy 'nose' - just skimming the body of the diff casing.

Once you reach the rubber 'O' ring you're home and dry, the remains should pull out without the fear of losing the circlip and cog off the end.

As the alloy body corrodes, it swells, pushing the gear off the end of the shaft. The circlip then becomes very distorted, like this .

Hope this helps.

Bob.

 

[diggerdave]

Nice one Bob, I like the sound of your method and it might help others to know what size of hole-cutter is needed.

I shaped the remains of the backplate using a powered hacksaw and a sharp chisel into a shape that I could get a heavy spanner onto and twist. I figured that the hammering of the chisel couldn't do any harm because it wasn't creating stress on the circlip, only rotational stress on the remains of the housing and the incidental torque would only be beneficial in breaking the corrosion seal. Same applies for twisting with the spanner, which stressed only the housing remains and not the circlip and cog. The photo below hopefully makes it clear how I shaped the backplate.

Funny thing: the shaft with the cog on it was of course corrosion-welded into the remains of the housing backplate, so when I twisted clockwise with my spanner to break the corrosion-seal, the difflock engaged (for the first time in many years!)

 

[BobMurphy]

Dave

Glad to see you got it out!

My memory is failing with old age, but I have a feeling that 24mm (as shown in my picture) was too large and 20 or 21mm was better. I can't be sure now but if anyone is going to use my method go carefully and don't chew the diff housing!

Fortunately I have accumulated a box full of these Bosch cutters over the years so am able to experiment a bit .

As an aside, I have found different sizes of gears on these diff lockers, maybe Toyota changed the design at some point !

Bob.