Tips & Tricks

Are Gearbox Additives Worth It?

Are Gearbox Additives Worth It?

Well it’s never really a good thing if you’re considering using gearbox additives…

And I am speaking from experience, my 120 Prado isn’t very new and has got a few gearbox niggles.

It’s done 470KMs as of writing this and the gearbox probably needs a rebuild, but it won’t happen yet.

So I thought, let’s chuck in some gearbox additives and run some tests – and find out if gearbox additives are really worth it.

Feel free to watch this video if you want to see a visual representation of this topic.

Let’s throw in some additives

So I threw in 2 squeezey tubes of gearbox additives from Penrite. This is about the right amount to throw in for my gearbox.

I had to take about 200mLs of gear oil to fit in these lubes.

I actually had a little look at the additives and they are quite thick in-comparison to gear oil.

And these products are made with teflon, similar to the non stick coating on your frying pans.

So theoretically these additives should do something…

Gearbox additives by Penrite.

These are the products I used from Super Cheap Auto, they were on sale for SCA members.

So what were the results?

I decided to do 2 test:

  • On a cold morning with a cold gearbox
  • In a warm gearbox after it’s been driven

So here is what I thought of the changes.

Cold gearbox results

I actually thought that gearbox additives might of made a small difference here.

I do think the gearbox was a little less sticky in the cold mornings. But we’re talking about maybe a 10% difference, there are no game changing results.

Warm gearbox results

The results here weren’t amazing…

I thought the gearbox pretty much functioned as normal.


Look let’s be real.

You’re getting what you’ve paid for.

I paid $30 buck for 2 tubes of additives, it’s not a $2.5k gearbox rebuild.

But in saying that, I don’t think the gearbox additive has hurt, especially in the cold weather!

Best Gearbox Additives!

I was recommend 3 different brands of gearbox additives, and I thought I would leave them at the end here.

Honestly do your own research, for what is right for your vehicle – this is just what people recommended me.

  • Nulon Smooth Shift
  • Red Line Shockproof Gear Oil
  • Penrite Ezy Shift

Thanks guys!