[smashbie]

Hi,

I'm wanting to add some kind of additive to my manual gearbox. The oil has been recently changed by my mechanic which has made somewhat of a difference but it does still seem a little 'crunchy', not to much that it grinds but it isn't 'smooth'.

Was thinking of adding: Smooth Shift Manual Gearbox and Diff Treatment - Nulon Products Australia

Is this easy to add? Can I do it via the engine bay? I've had a look at the workshop guides but it isn't clear where the gearbox filler plug is in an 09 FD SX Petrol.

Cheers.

[nzenigma]

Dont know your kms ????? so thats a factor in smooth shift. I have used Nulon products for decades and they are good.
Look up gear box filling, thats where it goes.

[mickd]

If box is full, you will need to drain by the amount going in .
Might be easier to dump the lot put additive in then top up.
If you don't have the gear,  leave it.

[smashbie]

It’s done 240ks hence a lot to do as unfortunately I only have limited history (no log books). Good in isolation, as I’m learning a lot about this car. The engine seems good as it’s quite responsive under load. Cheers.

[mickd]

Might pay to change engine air filter and  cabin filter ( ( inside glovebox)

[smashbie]

Both done.

This is what’s been done so far:

Oil, oil filter, fuel filter, air filter, cabin filter
Wiper blades all around
Replaces control arm Bush, flushed brake and clutch fluid, throttle body clean
Spark plugs and leads changed
Coil changed
Rocker gasket changed
Rear gearbox mount
Changed master window and rear passenger window switches
4 tyres
Flush and replaced coolant and manual transmission oil

Apparently starter motor and all belts were changed by previous owner.

Cheers.

[smashbie]

That being said too. When changing all of these things pretty much everything is genuine ie never been changed. Leads were genuine Hyundai for example.

I also have a knocking sound at very low speeds when turning the wheel. Mechanic thinks it could be steering rack ends and quoting $300. But hoping to hold off on that for now.

I think the shocks also need changing doubt they’ve ever been changed. I’d love to actually learn now to change that myself. I can get second hand struts with springs as one unit and from what I’ve read it’s fairly easy to replace as one unit.

Cheers.

[Jack Daniels]

If your box is the same as mine, then 75w-85 GL4 oil will be specified. This is not very common so many workshops will use 75w-90 which has very different viscosities than 75w-85. Several lubricant producers specify 75w-90 because they don't manufacture the correct grade, 75w-85.   Apparently the additive package in a straight GL4 will be better for the box than a GL4/GL5 kombi product.
  Do you have the correct spec lubricant in the box? That's probably more important than introducing an additional Fluid.

[smashbie]

My mechanic put in 75W-85.

[Jack Daniels]

My car is a 2008 and probably has the original fluid, I haven't been able to get hold of 75w-85 GL4 yet.  The Kia dealer can order some for 90 euro which is a bit steep for just 2 liter.  Have you changed the clutch fluid and bled the line?

[smashbie]

Yes clutch fluid has been changed as well. Thanks.