Diff oil change

Hi people,

Im about to change my diff oil, but how do i pour it in? do  i need a pump of some sort? if so whats it called and where can i get one?





Diff oil normally comes in a squeezy bottle. Put the spout in the hole and just squeeze the bottle—

You can also buy a large syringe type thingy majig! One of these


The diff is easy to get oil into.  The gear box a little less room.  Both can be done with the squeezy bottle but the above do da makes it much easier.

Thanks guys :wink:


Do i need Ramps?



Ramps make it easier, but is doable without—


Will this oil be ok?


That’ll do fine—

Comma 80W90 will also do fine. You can get this from Wilko and it will be much cheaper than Halfrauds. I bought Comma 75W90 fully synth for mine from our local trade motor factor and it was only £6/litre.

Ramps/stands might be useful to get some leverage, especially if the crush washers have been overtightened and/or are corroded. I had to use a breaker bar on mine and it didn’t help that a previous owner had chewed up the filler plug with a badly fitting spanner/socket. Use the correct 23mm and 24mm wrenches/sockets and use new crush washers on the drain and filler plugs.

I guess you can pay as much or as little for these types of oil. I prefered to go the other way and used Redline at about £15/L. It’s one of the oils that isn’t changed that often and I like to use a premium product.

There are some good oils here


Getting the crush washers is looking almost impossible.Found them on Ebay, anyone know the size?

Ill do it on Thursday my next day off, today is a little wet, prolly not in Aussie land.

MX5Parts, AutoLink or your local Mazda dealer parts counter will have them.

 If these washers are copper you can anneal them that is if you have access to a flame i.e. gas cooker or one of those little gas flame throwers, use a piece of wire and support the washer in the flame until it goes cherry red the douse in cold water the washer will have softened up a little and will make a good seal.

Ramps or axle stands are recommended that is unless you have a figure like racing snake make sure to chock the front wheels if you are to jack up the rear of the car.

The washers cost pennies from the local Mazda dealer, they are aluminium—

 Oh well but its a good tip

Diff washers are the same size as mk1 sump washers


thanks guys, sump washers it is then :wink:


This is from the FAQs—

The washers are Mazda part number 9956-41-800, they come in packs of 5. They measure

18.25mm id

24mm od

1.43mm thick [new thickness, the washer is aluminium and is designed to crush when the correct torque is applied].

Torque should be:

22-30ft/lb for the engine sump

29-43 lb/ft for the gearbox drain, 18-29ft/lb for the filler

29-40ft/lb  for the diff drain and filler/level plug

Spanner sizes needed

Engine sump 19mm

Gearbox drain 24mm, fill/level 14mm open ended spanner, or 16mm bi-hexagonal ring spanner

Diff drain 24mm, fill/level 23mm

Thanks for all the help, ill orderr the washers monday.

Once again thanks



Remember to drop the car down once you have filled the diff to allow the excess oil to come out of the fill hole. You may need to jack it back up to get a torque wrench on to tighten the filler bolt.

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