I have finally reached a stage in my life (46 1/2) where I feel able to change oils on my own cars. I take good care of my MX5 and i’d like to do my own oil and lube changes.
What i’d like to create or find is a shopping list of Engine, Gearbox, Diff, Power steering, Brake and Clutch fluids/oils and all related sundries eg.replacement washers with sizes, draining and filling equipment etc for my Mk3 NC (and all other models too as it would help owners or other models) but I can’t find one anywhere. Can anyone please confirm or correct/advise if the following is right and also advise on required volumes and where is best to buy them? Here’s what i’ve found so far.
Can a correct list be made a forum sticky if it hasn’t already?
Engine - ? Sump washer 14mm
Brake - Dot 4?
Clutch - ?
Diff- Full Synth Mobil 75w90 1ltr (NC takes 700ml)
Gearbox - Castrol Syntrans 75w90 GL4 3ltrs. (is this the same oil as used in the Diff?). Drain plug washer 18mm
Clutch feeds from brake fluid reservior so DOT 4 too.
Should be GL-5 I believe. Again, not sure of the size but sounds about right. You’ll need two washers if it’s a 6 speed.
ATF, Dexron II or higher. Not really a fluid that’s changed as a service item though.
8mm spanner for brake/clutch bleed nipples. 23mm & 24mm spanner for gearbox and diff plus a 14mm open ended if it’s a 5 speed. 17mm spanner for engine oil sump plug. Oil filter removal tool depending on tightness, try undoing it while it’s still warm. suitable container for draining fluids into and bits of tube and a funnel for refilling the gearbox or a fluid transfer suction thingy or just try and squeeze the oil in from the bottles the oil comes in if they have a spout. A piece of washer tube is good enough for bleeding the brakes with, just dangle the end into a suitable container (coffee jar for example).
However, regarding helping oneself finding the info etc.
Most of that info regarding types and quantities of fluids is in section 10 (Specifications) at the back of the NC Owners Manual that came with my car. There are a few permutations depending on type of gearbox, engine, climate, etc.
Clutch and brake share the reservoir in an NC. If bleeding the brakes the clutch is the last thing to bleed, and a must-do because the take-off is partway up side of the reservoir not on the base like the brakes.
The only significant omission I have noticed in Section 10 is to do with coolant type; although Section 8 (Maintenance and Care) does mention FL22 (premixed Mazda long-life special) along with lots of cautionary advice.
Of course the manual does not list details like specs for air filter, fuel filter, oil filter or sump plug washer. However every time I’ve bought an oil filter recently (GM car) the rubber seal ring and the sump plug washer came with the canister as a standard kit.
With the GM parts I found the dealer prices were cheaper than Halfrauds and competitive with on-line, and the parts were guaranteed and not fakes, and the parts sales staff were always helpful. I’ve not bought any bits for the MX5 yet (apart from an RX8 variable delay wiper stalk), instead I have just paid for a full service and MOT - lack of flexibility in aged joints also plays a part when deciding to balance cost vs convenience.
The Cstrol Syntrans 75W/90 is a gearbox oil that is used in the 6 speed gearbox box and is a GL4 oil and improves the gear change change at startup if the change is a bit stiff.
The Syntrans should not be used in the diff.
The 5 speed gearbox usually is not so fussy and it can use a 75W/90 GL5 oil which makes it easy to buy one type of oil for the diff and gearbox.
Interesting as I read a report recently that went in to great detail about differences between GL4 and GL5. It mentiones that GL5 contains more phosphers than GL4, which attaches to surfaces and offers wear protection.
However, these phosphers have a tendency to wear more of the yellow stuff away (bearing/bushes etc), than would normally occur with GL4.
It recommended not to put GL5 in to a gearbox for this reason, but diffs contain no yellow stuff so benefit from the added protection.
I believe that you are right regarding GL-5 oil in a gearbox not designed for it. Are modern GL-5 oils not backwards compatible with GL-4 though? I think, for example Fuchs Sintopoid LS is listed as GL-4 and GL-5. Certainly worth checking the oil that you’re planning to use though.
The spec requirement from Mazda changed on introduction of the facelift NC. Pre-facelift NC requires GL-4 or GL-5 in the 5 speed box and GL-4 in the 6 speed but facelift NC is compatible with GL-4 or GL-5 in both the 5 speed and the 6 speed box…
To be safe I used Castrol 75w-90 Syntrans (GL4) in my 6 speed NC ‘07’ plate and Castrol Universal 75w-90 (GL5/GL5) in the diff.
The only drawback with the above with the 6 speed is, you need 3 x 1ltr bottles as it takes just over the 2ltrs of the gear oil to complete the job. The 5 speed box the same oils but you will be ok with the 2 x 1ltr to fill, the diff in both models just 1 x 1ltr bottle.
For the engine I use Mobil 3000 FE 5w 30 x 5ltrs, it should take around 4.6ltr on the 2ltr engine and use a genuine Mazda filter.
The vast majority of garages have a big drum of 75W/90 GL5 and use it in both diffs and manual gearboxes.
I have used it in many Mk2, Mk2.5 and Mk1 gearboxes without an issue.
In this case, I wonder if it was Mazda not checking if the 6 speed was up to using GL5 but just said it would cause confussion so just keep the standard spec oil as in the book for the past 10 years or so.
Went to Mazda service centre this morning and picked up OEM Oil Filter and a set of five washers for the engine sump, diff and gearbox bolts.
I have a couple of questions and I need some more help before getting stuck in.
Is the use of engine flush recommended? I imagine it to be a sort of detergent which removes absolutely everything which has coated the moving parts and thus protects it from wear. I’m changing from Semi Synth to Full Synth and bought some Comma Xtech Full Synth 5w30 and I believe engine flush is recommended before switching.
Brakes. Is bleeding the brakes a straightforward thing (£10 Halfords brake bleed kit and dot 4) or do I need to also consider ABS and engine management?
Once again, I really appreciate your help with this. It’s the first time i’m attempting to do this myself and while i’m not entirely kack-handed, I like to know what to expect before I find myself stuck.
If the engine oil is clean of contaminants, and the filter looks clean, and no metal or gunge stuck to the sump plug, then a flush is not necessary. Modern oils and filters prevent sludge build-up, especially if they are changed before getting denatured and clogged.
If you have not already got a copy then you need a proper Workshop Manual if you plan to do any serious work on the car.
The section on the Brakes is comprehensive and answers all the questions. This link below is for the LHD Miata Manual and is in a collection of PDFs, but almost everything is relevant to both LHD and RHD, and common sense allows one to work out the differences.
Also understand that fully synthetic oil is just longer life oil not better oil. If you are going to change it regularly then I wouldn’t be over concerned.
For engine flush, if you want to, just put half a cup of diesel in the oil and let it idle for 10 minutes before draining.
A rubber glove is often as good as any filter removal tool. However if you do need one, the scissor pliers types are far better than the chain or knurled finger types which just split. You can always bang a screw driver through them as well.
It’s not just longer life Nick, synthetic oil has physically different properties to regular oil, film strength and resistance to higher temps, for instance.
There is no need at all to worry about synthetic or not.
The engine uses a 5W/30 A5
The six speed gearbox in the Mk3.0 uses 75W/90 GL4.
All the others gearboxes can use 75W/90 GL4 or GL5.
The diff 75W/90 GL5.
There are some other grades advised by Mazda but these are to spec in the UK.
The user only has to check those specs are on the bottle not worry about whethere it is synthetic or not.
The very latest non synthetics if you can find them as they are probably semi synthetic anyway are up to the job if the bottle has the above specs on it.
Suction gun, GL4 and GL5, 5w/30 FSynth, rubber gloves, OEM filter, replacement washers, door trim removal tool set for when I change the rusting window uprights (the ones which hold the 1/4 glass in and which rust at the bottom. Mazda quoted around £25 each for upgraded ones)…bought a jack today but the axle stands I bought the other day are too high, so they’ll have to be exchanged… wheel chocks worked a treat too.
Firstly, i’d like to thank you all for all the helpful and generous advice you’re giving me. I love my little car and I thoroughly enjoy looking after it…with your help of course.
So I’ve got all the gear and some idea. It’s a good start. I took one front wheel off and gave as much as I could easily get to a good rub over with a wire brush and some wire wool. Then i’ll paint the suspension arms etc so next time, all it’ll need is a wash down. I also picked up some caliper paint (Gold), but my neighbour reckons red would be better. dunno.
The ex-RX8 ARBs arrived and I can see that I could probably get to the ARB clamp nuts but i’m thinking my mechanic would find this much easier to do, with the car on a lift and they’ve already agreed to fit them for me.
Brake bleeding. i’m reluctant to meddle with this because I can see me running into trouble, so one more job for my mechanic though i’ll be there to see how it’s done for next time.
All in all, it’s early days and a bit faffy but I can already see that there are lots of easy jobs that I could do myself and I can barely wait to get going.
Thanks again and i’ll keep this thread running if you don’t mind, in the hope of being able to ask the questions as they arise.
Brake bleeding is straightforward and you don’t need the engine on. I usually start furthest from the master (rear left wheel) and use about 1L DOT4 doing 2 or 3 reservoir fills for each wheel. Do be extremely careful not to get air in the abs unit by letting the fluid go too low in the reservoir as it can be very difficult to purge. Do 5 pumps then check how far it’s dropped and top up etc. This little tool from Halfords is all you need for occasional use (the rubber pipe goes through the other hole in the plastic plate then onto the nipple with the plastic hole around it to keep it really tight on smaller nipples if working alone), http://www.halfords.com/motoring-travel/engine-oils-fluids/brake-clutch-fluid/europat-vizibleed-bleed-aid