7Up Posted November 1, 2020 Share Posted November 1, 2020 May I ask for advice - on a 420R, other than a lift to work on the car, what tools are required to change the oil in the diff and gearbox?Cheers all,Iain Link to comment Share on other sites More sharing options...
Roadsport06 Posted November 1, 2020 Share Posted November 1, 2020 This should be a good starting point for you. This was put together by a former member with Ford gearbox and diff.http://www.alcester-racing-sevens.com/maintenance.htm Link to comment Share on other sites More sharing options...
7 wonders of the world Posted November 1, 2020 Share Posted November 1, 2020 Final drives either Ford or BMW both have levels plugs, neither have drain plugs so you will need to suck the oil out with and oil syringe from the likes of Sealey.420 will most likely have a Caterham 6 speed or 5 speed Mazda gearbox, again both have level plugs, 6 speed has a drain, cant recall if the Mazda box does.NB the Mazda box also requires a small quantity of oil i the selector tower too - Mazda forums will give you the detail on this. Link to comment Share on other sites More sharing options...
Wrightpayne Posted November 1, 2020 Share Posted November 1, 2020 I sucked the oil out of my Ford diff via the boot with the car on the ground. Not sure about newer cars, but my part ply / part ally floor comes out by removing a few self tappers. I have cut the 'hoop' that goes around the filler neck so I dont have to disconnect the filler neck to get the ally panel out. Filling is easier using gravity too!Have a look and weigh up the entry options! Ian Link to comment Share on other sites More sharing options...
StevehS3 Posted November 2, 2020 Share Posted November 2, 2020 What is the recommended interval for changing BMW open diff and Ford 5sp gearbox oil please. Link to comment Share on other sites More sharing options...
timb2117 Posted November 2, 2020 Share Posted November 2, 2020 Hi Iain, I know this looks a bit game of thrones :) - I found the clearance between the 6 speed gearbox and my tunnel a bit tight so hacked off an allen key then welded it to a bit of spare steel. This gives plenty of leverage in a small space and gets the fill/level plug out neatly.Hope it helps on your mission. Tim Link to comment Share on other sites More sharing options...
ScottR400D Posted November 2, 2020 Share Posted November 2, 2020 That looks good Tim. I use a slug cut off the end of an Allen key and turn it with a ring spanner. Link to comment Share on other sites More sharing options...
Wrightpayne Posted November 2, 2020 Share Posted November 2, 2020 For 22 years I've just use a severely cut down allen key on the gearbox, with a short bit of steel tube to increase advantage. I find sliding under the car from the opposite side to the plug works best, as your fingers then naturally bend towards the plug / fill hole.Ian Link to comment Share on other sites More sharing options...
Baggiebird Posted November 2, 2020 Share Posted November 2, 2020 As has been said Caterham's own 6 speed gearbox has a drain plug. Both it and the filler/level plug are 10mm allen key but the filler plug access is very tight so you either need a tool such as Tim showed above or a cut down allen key that you can work with a 10mm ratchet spanner.For the differentials you will need a suction pump if you are renewing the oil. Link to comment Share on other sites More sharing options...
aerobod - near CYYC Posted November 2, 2020 Share Posted November 2, 2020 One thing to be careful on the 6-speed is that (at least on my 2012 R400) the fill plug is 3/8", the drain plug is 10mm. From the assembly manual: Link to comment Share on other sites More sharing options...
7Up Posted November 2, 2020 Author Share Posted November 2, 2020 Thanks to all! Have purchased the diff oil, trying to work out the best gearbox oil now. Link to comment Share on other sites More sharing options...
Adam Godfrey Posted November 3, 2020 Share Posted November 3, 2020 After struggling unsuccessfully to undo the drain plug out with a cut down allen key, I ended up removing the top plate (5 speed type 9 gearbox) and sucking the oil out with a Sealy syringe and refilling. Link to comment Share on other sites More sharing options...
John Vine Posted November 5, 2020 Share Posted November 5, 2020 Re #9:...or a cut down allen key that you can work with a 10mm ratchet spanner.As the ratchet spanner works in the one direction, take care that you don't trap it on the key as the plug unscrews. IIRC, a certain regular contributor didn't, and ended up with the key hard up against the tunnel side, with no way to screw the plug back in so as to release the spanner!JV Link to comment Share on other sites More sharing options...
ScottR400D Posted November 5, 2020 Share Posted November 5, 2020 JV, that’s a very good point. The bit I use is about 15mm long so doesn’t hit the tunnel before the plug is out but what you say is quite possible. Never dawned on me before though!And as Aerobod says the fill and drain are two sizes, 3/8” and 10mm. Link to comment Share on other sites More sharing options...
7Up Posted November 5, 2020 Author Share Posted November 5, 2020 Does anyone know the size or description for a magnetic diff drain plug? (I've the BMW titan)thanks Link to comment Share on other sites More sharing options...
ScottR400D Posted November 5, 2020 Share Posted November 5, 2020 This: https://www.ebay.co.uk/itm/283500049956but it’s for the filler plug, there is no drain, but if there are any ferrous bits banging about it will hopefully pick them up! Link to comment Share on other sites More sharing options...
Baggiebird Posted November 11, 2020 Share Posted November 11, 2020 All interesting as on my 6 speed gearbox (1996) and yes, the level and drain plugs fit a cut down section of 3/8" Allen Key. As John says take care if using a ratchet spanner.I have just filled the box with Redline MTL using a Sealey plunger operated mini pump. I was a bit sceptical how effective this would be as each stroke is about 10cc. However it worked a treat to fill approx. 1.5 litres quite quickly. The pipe comes with an alloy U bend at the end and there was just enough room to hook this into the filling hole in the narrow gap between the gearbox and tunnel. Link to comment Share on other sites More sharing options...
Wrightpayne Posted November 11, 2020 Share Posted November 11, 2020 For those with the 5sp ford box there was a post a few years ago about putting a cap in the pressed metal lid and making a dip stick. Also ideal for filling and evacuation.Ian Link to comment Share on other sites More sharing options...
ScottR400D Posted November 12, 2020 Share Posted November 12, 2020 #17. Yes the Sealy pumps are quite good, I’ve been using one for both the box and diff since I built my car. A word of caution; I’m certain the the drain and filler are different sizes in many 6 speeds The fill is 3/8” and the drain 10mm. A cut off 3/8” will undo both but it’s a poor fit in the drain plug and there’s a risk of damage, it being about .020” smaller than it should be. Link to comment Share on other sites More sharing options...
7Up Posted December 1, 2020 Author Share Posted December 1, 2020 When you originally posted this link, they were out of stock. Now they are back in, but the page looks different. Can you confirm this is the correct plug for the BMW/titan diff? Thanks! https://www.ebay.co.uk/itm/283500049956 Link to comment Share on other sites More sharing options...
ScottR400D Posted December 1, 2020 Share Posted December 1, 2020 Yes, Iain, that’s the one! Link to comment Share on other sites More sharing options...
Aerial_stu Posted January 7, 2023 Share Posted January 7, 2023 Hello, can anyone help me with the tool name / size required to open the fill/drain bolt for the BMW diff on my 310s please? just under the "m" of Caterham. Link to comment Share on other sites More sharing options...
Dixa1225 Posted January 7, 2023 Share Posted January 7, 2023 14mm Allen key Link to comment Share on other sites More sharing options...
Aerial_stu Posted January 7, 2023 Share Posted January 7, 2023 Thank you Link to comment Share on other sites More sharing options...
Area Representative Geoff Brown Posted January 8, 2023 Area Representative Share Posted January 8, 2023 The important accessories are patience, limbo qualified & prepared to create some oily mess.I know people do it but IMO accessing via the boot floor for the diff is as much if not more of a faff than just going 'up & under'. Link to comment Share on other sites More sharing options...
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