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I'm about to do a manual transmission oil change, just picked up some Nulon 75W90 Fully synthetic gear oil.
I've heard different methods ranging from using a pump to filling up the gearbox with a long hose up through the exhaust headers..

Filling up using a hose, funnel and threading it down through the exhaust headers and into the gearbox filler sounds like the easiest, has anybody used this method and if so.. what size hose approx. do I need? I haven't looked at the underside of my gearbox so I have no idea how big the filler how is..

i use the hose way though its easier with a helper.

i cut an ordinary garden hose fits snug in the NB8B diff and gearbox filler hole.

u also will need four car stands and a good jack if jack cant slide underneathfit drive a wheel onto piece of wood or something similar.

never get underneath with only a jack...... even though heaps of people have done it, its just not worth it.

I never get underneath my MX5 without a safety stands. I've got a trolley jack that just fits underneath my car so its all good, been changing my oil and working on the car like this..


anyways, is the filler hole to the NB tranmission the same size as a NA? I've used garden hoses and a funnel to fill up automatic tranmissions before and it works quite well.

spikes wrote:...threading it down through the exhaust headers ...,

Through the wheel well is easiest.

Also gear lever turrett needs filling separately on the 5 speed.

93_Clubman wrote:Also gear lever turrett needs filling separately on the 5 speed.

Gear lever turret?

This is when you take out the gearstick (super easy, just look yourself youll work it out) and fill straight from inside the cockpit, this is how I fill my 6 speed.

Dann

NitroDann wrote:This is when you take out the gearstick (super easy, just look yourself youll work it out) and fill straight from inside the cockpit, this is how I fill my 6 speed.

Dann

Yeah just did some googling and found this neat photo article

93_Clubman wrote:Also gear lever turrett needs filling separately on the 5 speed.

not according to Mazda it doesnt?

I've got the Mazda workshop manual and it makes no mention of touching the gearstick, simply drain the oil from the gearbox, and then refill it.

although mine is an NB, maybe the NA was slightly different?

hks_kansei wrote:

93_Clubman wrote:Also gear lever turrett needs filling separately on the 5 speed.

not according to Mazda it doesnt?

I've got the Mazda workshop manual and it makes no mention of touching the gearstick, simply drain the oil from the gearbox, and then refill it.

although mine is an NB, maybe the NA was slightly different?

Nic, NA6 & NA8 5 speed requires turrett to be emptied & filled separately. My understanding is same applied to NB8A 5 speed, however NB8B 6 speed was different, & so didn't require filling separately. Also my understanding that NB8A 10AE & Heritage 6 speed GB differs in some minor respects to NB8B 6 speed GB, so not sure how the rule applies with them. Doesn't really surprise me Mazda don't mention it as it's something that seems to get overlooked.

hks_kansei wrote: I've got the Mazda workshop manual and it makes no mention of touching the gearstick, simply drain the oil from the gearbox, and then refill it.

If your goal was to simply replace the oil that relates to the gears, then yes, you don't have to change the turret oil. The oil in the turret (under the gearknob/stick) only relates the shifter arms and doesn't impact the quality of the oil on gears themselves. So technically speaking, the Mazda workshop manual is correct - it isn't related or required.

I'd bet that if you think you need to change the gearbox oil, then chances are the gear turret boots are worn/broken and if you are replacing them, you'd may as well replace the turret oil too

G

spikes wrote:Filling up using a hose, funnel and threading it down through the exhaust headers and into the gearbox filler sounds like the easiest, has anybody used this method and if so.. what size hose approx. do I need? I haven't looked at the underside of my gearbox so I have no idea how big the filler how is..

This. Hose size - whatever fits in the hole, and you can stick a funnel in to, I can't recall.

PS getting off the square head filler bolt is a right c....... well let's just say it makes me swear more than my mother in law who has Tourettes.

make life easy on yourself and buy something like this: http://www.supercheapauto.com.au/online ... escription

They also have one you can buy without the bottle that will screw on to the bottle the oil comes in, I have one of those.

I jack the car up, undo the filler plug and then under the drain plug...They should not be silly tight. I then lower the car as you will not get all the oil out with only the front jacked up.

I then get the car back in the air, drain plug in and use the handy transfer pump to get the oil in with no mess, no funnels and no lengths of hose.

I jacked both the front and rear end up so it'd sit level and changed the diff oil as well.

Filler plug was pretty easy, you just gotta wait for the car to cool down so the exhaust headers and pipe won't burn you. Undo with a 15mm open ended spanner and threaded a 9/16" clear nylon hose into there through the engine bay with a funnel at the other end and tipped in the oil. Was really easy and no mess at all..

Diff oil change was so easy to do, dead set about 5 minutes to get done.

Change my transmission oil a few weeks ago. I tried both putting the pipe next through the engine bay next to the exhaust and through the passenger side wheel well. Found going through the wheel well was easier for me. Funnel into hose and end of hose into fill hole. Clear hose is better if you have it.

Even when cold I found that filler plug hard to remove, I cleaned the threads before putting it back on. Oh and always remove it before you remove the drain plug.