Gearbox and diff oil additives. Yay or nay?

Gearbox and diff oil additives. Yay or nay?

Author
Discussion

nomis36

Original Poster:

314 posts

131 months

Thursday 20th May
quotequote all
I’ve had my quaife atb equipped diff bearings replaced. I’m going to refit it this weekend but started thinking about maybe adding a friction reducer when I fill it. These Quaife LSD’s don’t require any special oils so will be using the standard 75/90 stuff.
On the gearbox side it’s the original unit with 158,000 miles on it. I changed the oil in that recently which made all the gear changes better but it’s still a bit tight engaging first, especially when cold.

Anyway, what are your thoughts on additives?

rustednut

591 posts

14 months

Thursday 20th May
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nomis36 said:
I’ve had my quaife atb equipped diff bearings replaced. I’m going to refit it this weekend but started thinking about maybe adding a friction reducer when I fill it. These Quaife LSD’s don’t require any special oils so will be using the standard 75/90 stuff.
On the gearbox side it’s the original unit with 158,000 miles on it. I changed the oil in that recently which made all the gear changes better but it’s still a bit tight engaging first, especially when cold.

Anyway, what are your thoughts on additives?
The right oil for the right application is all that is needed.

SlimJim16v

3,570 posts

110 months

Thursday 20th May
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I would use Millers Nanodrive NT+ in the diff.

Gearboxes are a bit trickier. I've read good things about Redline, but also some horror stories. I went for Motul.

Pastie Bloater

694 posts

130 months

Tuesday 25th May
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Gear additives are a waste of time and money, ring and pinion treatment works but not on a used diff, only new.

imagineifyeswill

1,169 posts

133 months

Thursday 27th May
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I would beg to differ, had a customer with a rover 214 with a bit of a noise of the gearbox possibly noisy bearing. He didnt want to spend money on a rebuild or replacement gearbox thought he would trade it instead. To try to quiten it temporarily put in a tube of Slick50 gearbox treatment, it quitened it so well he was still running it 3 years later.

Pastie Bloater

694 posts

130 months

Thursday 27th May
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In that case he'd have probably still been driving it 3 years later with the noise (if he could put up with it).
An additive can't cure a worn or failing gearset, and from a mechanical engineering POV additives are snake oil.
They can reduce noise but so can sawdust, and using them in OPs case achieves nothing.
As an aside I'd be interested to hear what Quaife say about using friction reducers.

SlimJim16v

3,570 posts

110 months

Friday 28th May
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Pastie Bloater said:
As an aside I'd be interested to hear what Quaife say about using friction reducers.
Maybe in a dog/crash/unsynchronised g/box?