Any point changing gearbox oil if it's light and golden?
Any point changing gearbox oil if it's light and golden?
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Discussion

TroubledSoul

Original Poster:

4,665 posts

223 months

Wednesday 14th May 2014
quotequote all
I was going to.... to try and diagnose a strange noise but then checked the oil this evening and found that it looks like new. I've only had the car a week or so so it's possible it has already been done, probably by somebody also trying to diagnose the noise and then selling up as the oil change didn't fix it!

So is it worth me changing it, or would I be wasting my time and money?

kambites

71,447 posts

250 months

Wednesday 14th May 2014
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In my experience gearbox oil always looks perfectly clean, regardless of how old it is. I don't think that necessarily means it hasn't started to lose its lubrication properties, though. That's one of the problems with gearbox oil. It's nigh on impossible to tell.

J4CKO

46,819 posts

229 months

Wednesday 14th May 2014
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In my experience, (manual) gearbox oil doesn't really change colour, engine oil takes more stick and the blackness is particles of soot, it also gets much hotter and gets contaminated with water, the gearbox is a comparatively civilised environment, but the oil does get hot and it does get used, but will look very similar to when it went in, my explanation is it is a bit like a piece of chewing gum that you have chewed for ages and its gone all weird, it looks the same but at a molecular level, its knackered and my understanding is that is what happens to gearbox oil, looks ok but is actually worn out.

Boobonman

5,700 posts

221 months

Wednesday 14th May 2014
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Is it an auto? I've seen the oil from them look slightly frazzled on occasion. My guess is prev owner has already recently tried to fix the noise and you need to look elsewhere.

Jimmyarm

1,962 posts

207 months

Wednesday 14th May 2014
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kambites said:
In my experience gearbox oil always looks perfectly clean, regardless of how old it is. I don't think that necessarily means it hasn't started to lose its lubrication properties, though. That's one of the problems with gearbox oil. It's nigh on impossible to tell.
IME, old gearbox oil always looks like crap and smells horrid.

I work as a 'Mechanic'

If it is new and golden it has been changed 'recently', the car has done low mileage or it is a new ish car....

What flavour of vehicle is it ?


Edited by Jimmyarm on Wednesday 14th May 20:17

TroubledSoul

Original Poster:

4,665 posts

223 months

Wednesday 14th May 2014
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53 plate Impreza WRX Wagon. Had it just over a week. Very happy with it besides a strange "hissing" noise when the gearbox is in 1st, 3rd, or 5th, so the shifter pushed forward.

It's very strange. Doesn't matter if the clutch is depressed or not etc. Definitely not turbo noise as it's coming from under the centre console and it goes away instantly in 2nd or 4th....

Boobonman

5,700 posts

221 months

Wednesday 14th May 2014
quotequote all
Based on your description, I wouldn't be worrying about that. How obvious is it? Definitely only audible in the gears you said?

TroubledSoul

Original Poster:

4,665 posts

223 months

Wednesday 14th May 2014
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Yes, no other symptoms either. It's not something I've ever experienced before.

littleredrooster

6,358 posts

225 months

Wednesday 14th May 2014
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One of the bearings on the first-motion shaft is goosed. It will probably not heal itself, unfortunately.

TroubledSoul

Original Poster:

4,665 posts

223 months

Wednesday 14th May 2014
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I see. Is it something that would be done alongside a clutch change? Will it get any worse/damage the gearbox or is it just an annoyance to live with?

A.J.M

8,382 posts

215 months

Wednesday 14th May 2014
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When i changed the F/R diff oils in my car, it also came out light and golden.

I changed it anyway. There was no record in the service books of the diffs being done and with 117k done i changed it.
Curiously, we did my mates identical car's oil at the same time. Even with 15k less miles and 2 years newer, the oil came out looking like Cola, it was so black..

If the issue is internal in the box, you'll be putting new oil in it once it's rebuilt anyway.

TroubledSoul

Original Poster:

4,665 posts

223 months

Wednesday 14th May 2014
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I don't know for sure that it is! Easy enough to just change the oil anyway so I will, but not holding out much hope for a miracle.

Axionknight

8,505 posts

164 months

Wednesday 14th May 2014
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kambites said:
In my experience gearbox oil always looks perfectly clean, regardless of how old it is. I don't think that necessarily means it hasn't started to lose its lubrication properties, though. That's one of the problems with gearbox oil. It's nigh on impossible to tell.
At the other end of the spectrum I have changed the fluid on an old Volvo 850 and V70 (automatics) and found it to be dark brown in colour and on one of the occasions it smelled like it had been burning - it should have been a cherry red and obviously not "burny", both cars had dubious shifting properties and a good flush through of decent fluid solved any issues the cars were having.