Can anyone tell me what aTF to use in a Mk1 Eunos 1.6 auto?
Any ATF will do if it is Dexron II or III.
Is Dexron II or III also ok in the Mk 2? I thought I’d read somewhere that Dexron II is not suitable. I’m thinking of a fluid change, but have been advised to leave well alone if there are no problems; and there aren’t. It’s not really dirty, a light reddish brown, but don’t know how long it’s been in there. Original/20 years/70,000 miles? I would change it with engine running, drain fluid from return line from cooler, new fluid in simultaneously down filler tube, all carefully measured, in and out…Won’t touch the sump filter. Worked fine on my SAAB. Any thoughts, anyone, particularly on which fluid? Thank you.
Dexron II is fine. I have no opinion on whether you should bother changing it or not, sorry.
Light red-ish brown is OK really, but on the cusp of a change out.
I expect you are aware fresh claret colour is ideal.
Your current fluid is getting tired, what more is there to expect.
Had mine nigh on 15 years, but only flushed it out 5 years back with around 110,000 miles on.
It was ok-ish like yours, but I can tell you it was much smoother with new ATF and a bottle of American Forte autotrans conditioner. There was no filter swarf to speak of either but since I’d bought a new one, in it went. I expect the box to outlast both me and the car now.
So long as the ATF has no hint of rotten eggs, it’s a toss up what way you choose.
It’ll likely soldier on for possibly years without complaint but it’s not going to be at it’s very best either.
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Thanks for that. Any thoughts on my method, draining and filling at same time?
Best get it ramped frankly. Easy job for your local garage.
Armed with around 6 litres of ATF and a new transmission pan gasket, drop the old stuff out, check gauze filter for muck and clean it with brake cleaner or similar then MAKE SURE it’s dry as a bone.
Clean gasket surface area surgically , replace pan, then refill slowly with a filler cone to around 5 litres ONLY through the dipstick tube, then go through the gate with the tranny warmed up obviously with the hand brake on tight if you are solo ( OR… preferably with drive wheels in the air)…but best with a second man hard on the brake pedal (!) to circulate the new ATF. Then trickle in further ATF until the dipstick is up to its max.
** You need to take a bit of time checking the long dipstick while the ATF is HOT-ish NOT when cold**
You can phaff around with the radiator matrix pipes but it’s a two man job with potential pitfalls disturbing old piping and I’d not touch them. What ain’t broke is best left alone.
You will not get all the old stuff out.
The torque converter keeps as much a 1&half litres, but the new stuff will be more than sufficient to make the job viable.
Add a bottle of Forte Auto Tranny conditioner… optional. It makes the difference in my opinion. It’s designed to swell up tired seals.
Might as well check your PAS level…uses same stuff.
TBH, it’s a half hour / hours session at a decent garage with a 2 post lifter.
Might sound complex, but it’s not. A simple easy process tbh.
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Thanks for that. I’m probably going to renew the radiator and its ATF hoses soon anyway, so I’m inclined to do it then. The pipes from the gearbox look good, and easy to get at, so keeping everything clean, I’ll disturb less than dropping the pan. Do you agree it’s definitely Dexron 11 or 111?
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Cant recall re 11 or 111.
I could barely recall my reg plate the other day.
Only had it 15 years…or is it 14…maybe 15.
Oh…I just said 15…I think.
Who am I? 
Hi there,
Just reading this thread as I reckon my 1992 Eunos Automatic could probably do with auto fluid change too.
There’s a slight whiny sound coming from the centre console between the seats but it’s probably due to cold start ups.
Fluid doesn’t look horrid but some fresh stuff might be a good plan.
How did it go please and what grade fluid did you go for? Dextron 2 or 3?
Many thanks!
Hi there,
So just to confirm really;
You reckon about 6 Litres of ATM Fluid?
MX-5 parts says full capacity 6.7 Litres but I understand that not all fluid comes out as you say.
I’m planning on getting Mobil ATF 220 as it seems to be good for what I need:
- Mobil ATF 220 is a high performance, fluid for automatic transmissions in older vehicles specifying Dexron IID.
I’ll be getting the garage to do the change, so all I need to do is get the parts;
New gasket, New Filter, 2 New Drain Plug washers (assuming that’s the right amount?)
Then whilst I’m there thinking a couple of Magnetic Drain Plugs (one or two do you think?)
Then I’ll likely get washers and drain plugs for the rear differential as I’ll probably get that done at the same time…
Oh plus I may get them to change Power Steering Fluid (same fluid as the ATF 220 I believe?) so not sure if it’s just the fluid for the power steering or do I need any other washers/ knick-knacks?
I’ll probably ring MX-5 Parts as they’re quite knowledgeable, but since you’ve doe the Auto Fluid Change any advice is welcome!
Thanks in advance!
Sorry, I only just read your posts, Mk1-GNW. Despite saying nearly three years ago that I’d change the ATF, it’s still waiting to be done! I’m definitely inclined - when I get round to it - to drain it from the return hose from the cooler with the engine running, and simultaneously filling with fresh ATF down the filler tube.Worked very well on my old SAAB. No bothering with pan, gasket, filter. You need to be really organised with, say, 20 or 25 containers each with 1/2 litre of ATF ready to pour in at the same rate as it’s emptying. So you need someone standing hard on the brake and running it through the gears, someone checking and telling you how much is coming out - guiding the emptying hose into, say, litre or two litre bottles - and you filling the new ATF at the same rate. When it’s coming out clean it’s done. Measure how much came out. Count your empty 1/2 litre containers. Out/in should match. Three person job. You don’t change the filter, but I understand there are serious problems replacing one of the bolts/nuts which secure the filter, so leaving that alone sounds like a good idea to me. If it ever gets to the top of my list, I’ll let you know how it goes. Very clean chilled soup containers with lids are ideal, each filled with 1/2 litre of ATF and ready to hand as the job proceeds. Suitable funnel in the filling tube, of course.
Perhaps someone who knows what they’re talking about would care to comment on that method. If it worked without a hitch on my SAAB, is there any reason not to use this method on my NB?
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Hello I need some help/ advice please!
I took my Mk1 Eunos Roadster / Mazda Mx-5 to a specialist gearbox centre on Monday,
took the gasket and filter, along with 7 litres of ATF 220 fluid.
(For some reason it was cheaper to buy individual bottles of ATF than a 4 litre so I supplied 7 1 Litre bottles.)
Job has been done, picked up the car and in the boot are 3 litre bottles untouched.
So they’ve only used 4 litres.
Have they done the job properly or what?
Please advise I want to know before I ring them up and challenge them about it!
1st thing is to check the dipstick that is mentioned in a previous post just to make sure it is full.
You never get it all.
Torque converter holds up to or around 2 plus litres… at least.
As I said before.
Then there is the radiator which is a dual matrix affair cooling both water coolant and ATF. So yes, adding it all up it looks like they did a pretty decent enough job by probably just draining the box itself.
Some folk wait a bit for few hundred miles and do it again with remaining stuff to dilute old stuff further…but really…probable overkill. I think you will be fine.
As said, check the levels and shove the selector up and down the gate a few times then check it again.
So long as the level is good, so are you.
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Ah thank you that’s a relief.
I have done some enquiries about it and heard the same. I hadn’t even heard of a torque converter and didn’t realise it also went through the cooler.
I thought that as an option; to further dilute out the old stuff, which would be fine if there was a plug to undo but no such thing on the automatic it’s just the panel and gasket.
I asked the place that did it (happy to talk it over) if I could siphon out some fluid through the dipstick and then top up with new but he reckoned just best to leave it alone.
I’ll work the gearstick gate a bit and then check the dipstick level.
No worries.
Glad to help.
Happy Kickdowns!
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