Gearbox oil

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AndrewJZX100
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Re: Gearbox oil

Postby AndrewJZX100 » Thu Aug 28, 2014 12:01 am

sorry to dig up an old post, and with a bit of a novice question to boot, but this has been bugging me for some time.


Are you guys just pouring the g/box oil into the box from the shifter opening, or getting it into the fill hole on the side of the box somehow? (assuming the MX5 box has one, I can't say I've had a good look)

just thought I read somewhere that the 6 speed box has a remote shifter housing and not to fill the box via it.

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hks_kansei
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Re: Gearbox oil

Postby hks_kansei » Thu Aug 28, 2014 12:25 am

Use the fill hole.

That's why it's there.
Don't fill via the shifter housing, apart from wasting time in pulling apart half the interior you can't correctly judge the correect oil level in the box from up there.

You can buy a pump bottle for about $30 or so to do the job properly.
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93_Clubman
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Re: Gearbox oil

Postby 93_Clubman » Thu Aug 28, 2014 12:17 pm

AndrewJZX100 wrote:thought I read somewhere that the 6 speed box has a remote shifter housing and not to fill the box via it.

The 5 speed can't be filled via the turret as it's self contained.

AndrewJZX100
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Re: Gearbox oil

Postby AndrewJZX100 » Thu Aug 28, 2014 3:11 pm

hks_kansei wrote:You can buy a pump bottle for about $30 or so to do the job properly.


That makes more sense, was envisaging much difficulty trying to pour the oil from a regular bottle into the side of the box while its in the car lol.

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hks_kansei
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Re: Gearbox oil

Postby hks_kansei » Thu Aug 28, 2014 7:02 pm

Some people have made do with long lengths of hose, a funnel, and then snaking the hose up through the engine bay to pour via.

But, the pump is just so much easier.

$30 give or take, I've seen them a Autobarn and I think repco.
Image

Look for that.
The hooked nossle goes into the fill hole, and just pump until the gearbox oil starts to overflow.

Diff is the same, and depending on what diff you have in the car is generally the same oil as the box.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

Mr Morlock
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Re: Gearbox oil

Postby Mr Morlock » Thu Aug 28, 2014 8:19 pm

HKS is right- no workshop should be without one. Another thing is an automotive syringe type - I have had one for many years and its useful for filling and also for taking liquid out e.g. stale petrol out of a lawnmower etc etc. All these things are available in automotive supply shops and often shown in catalogs.

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gslender
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Re: Gearbox oil

Postby gslender » Thu Aug 28, 2014 10:48 pm

hks_kansei wrote:Some people have made do with long lengths of hose, a funnel, and then snaking the hose up through the engine bay to pour via.

But, the pump is just so much easier.


Having tried both methods, I would do the long hose snaked via the engine bay with a funnel - much easier, less mess than a pump bottle for clean up, and works as quick, plus you get to be upright when doing it. Only downside is that you need to be aware of how much you are pouring or it will over fill, but I do that anyway and catch the excess in a clean container and put back in the oil container. Your supposed to fill to the top of the fill hole anyway - a little more only drains out anyway.

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KevGoat
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Re: Gearbox oil

Postby KevGoat » Thu Aug 28, 2014 11:03 pm

Also always used the pipe and funnel method for gearbox. Used syringe for diff.

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AndrewJZX100
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Re: Gearbox oil

Postby AndrewJZX100 » Mon Sep 01, 2014 3:50 pm

Working at Toyota we'd use the 20l drums with their own pump, never thought to look up a small, home garage based equivalent until now.

hks_kansei wrote:$30 give or take, I've seen them a Autobarn and I think repco.
Image



You'd think having worked at Autobarn I'd know of this little gem, but we never stocked such an item lol.


Thanks for the help all, I am now enlightened :D

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Re: Gearbox oil

Postby Silvia » Sun Sep 07, 2014 1:11 pm

Another vote for Redline MT90 impressive improvement to cold gear changing and gearbox generally.
Got it for half Bursons price by checking internet for sellers and used cheap pump to fill.
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Aussie Stig
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Re: Gearbox oil

Postby Aussie Stig » Fri Sep 12, 2014 1:48 pm

And just when I thought I had worked it all out I found this....

Not recommended:
Redline MT-90 & MTL: These used to be popular choices... until people found abnormal wear, and conflicting information arose about this fluid being appropriate for hypoid gear transaxles. It is also a poor choice fluid in cold climates as it causes difficult shifting until the car is sufficiently warmed up.
Royal Purple: subpar product not even worth discussing.

GL-4 vs. GL-5: According to a transmission rebuilder, when GL-5 synthetic gear oils were first introduced , they contained high amounts of reactive sulfur harmful to yellow metals, such as the brass components in transmissions. So, theoretically, and according to the expert, modern GL-5 gear oils (now which most contain no or low reactive sulfur) should be fine to use.
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marty085
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Re: Gearbox oil

Postby marty085 » Fri Sep 12, 2014 1:54 pm

Aussie Stig wrote:And just when I thought I had worked it all out I found this....

Not recommended:
Redline MT-90 & MTL: These used to be popular choices... until people found abnormal wear, and conflicting information arose about this fluid being appropriate for hypoid gear transaxles. It is also a poor choice fluid in cold climates as it causes difficult shifting until the car is sufficiently warmed up.
Royal Purple: subpar product not even worth discussing.

Source? Or did the transmission rebuilder say this?

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Re: Gearbox oil

Postby Silvia » Fri Sep 12, 2014 2:16 pm

Causing difficult shifting until warmed up is exactly what MT90 does NOT do - it makes a most welcome improvement to this.
and that's from my and dozens of others direct experience
Can we therefore dismiss all the other "evidence" that was found?
I would.
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AndrewJZX100
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Re: Gearbox oil

Postby AndrewJZX100 » Fri Sep 12, 2014 3:18 pm

I'll throw a different outcome into the mix, my shift quality seems to be all over the shop after putting MT90 in it.

Old oil would be very stiff on the first few gear changes out of my driveway, but would come good reasonably quickly and once warmed would be generally fine, not 'hot knife through butter' quality but not worthy of complaint. I've no idea what oil it was unfortunately (was in the car upon purchase)

The MT90 is smoother slotting into first or reverse after sitting for a while, and generally much better in the first couple of gear changes, but after that it's a bit erratic. sometimes I'll get 2nd to 3rd so smooth it's barely discernable that there is mechanical movement going on inside the box, other times it'll be so stiff trying to engage the synchro I have to back off the pressure and go again. 3rd to 4th is mostly ok, not brilliant but not worse than before, but with the occasional very stiff change. 5th and 6th are pretty much as they were too.

I havent taken it on a drive longer than about half an hour yet, but it's been up to operating temp and still given me these issues.

Overall I'd hardly rave about it, the old oil was at least 2 years and 20ish thousand kays old and the fresh MT90 barely feels like an upgrade.

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Aussie Stig
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Re: Gearbox oil

Postby Aussie Stig » Fri Sep 12, 2014 3:23 pm

Royal Purple gear oil crap, accelerated wear with MT90 ??? Sacrilege.
Just saying there seems to be a sniff of snake oil about gear oil choice.

http://www.cabby-info.com/transmission.htm#Fluid
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