T5 wc problem

mike-b · Post by **mike-b** » Sun Aug 26, 2012 2:40 pm

Hi All, Having posted praise for "Gearboxman" I am hoping not to eat my own words.
When I collected my `box I was told not to use any ATF but 75w/90 semi-synthetic gear oil that they sold.
I now get a whine on all gears. All my reading states a good bo`x that whines is due to either too low a level of oil or the wrong sort/grade.
Any ideas anybody?
The clutch, spigot & prop have all done less than 300 miles from new.
The gears change with ease.
many thanks, Mike

ian.stewart · Post by **ian.stewart** » Sun Aug 26, 2012 4:31 pm

Im with sidecar there, if you have an aftermarket uprated gearset, its highly possible they have less of a helix on them, which will make them noisy

sidecar · Post by **sidecar** » Sun Aug 26, 2012 5:25 pm

MY T5 with close ratio gears whines in all but 5th gear, the box was built by Gearboxman. They reckon that the 'nearly' straight cut large teeth are the cause. I use Morris semi syth in it. I guess you could try AFT in yours to see it it goes quiet. Personally I don't like the idea of ATF in a manual box. (I guess LT77 and R380 boxes and tales of them not lasting put me off the stuff)

DaveEFI · Post by **DaveEFI** » Sun Aug 26, 2012 5:52 pm

If it's been re-built using a mixture of new and used gears, it will likely be noisy. Gears tend to bed into one another. This is why there's such a big variation in 'recon' prices. To do the job properly requires all the internals replaced with new. A noisy box may last quite well, though.

sidecar · Post by **sidecar** » Sun Aug 26, 2012 6:15 pm

I guess you would know if the gear set was close ratio, it's not the sort of thing that you would end up with by accident. (Well I'd be very surprised)

I went for a close ratio set because I wanted a 2.5:1 first gear, this suits my engine and diff ratio, the gearbox housing has to be machined in order to fit the gears. (The actual gears are made by Quaife)

mike-b · Post by **mike-b** » Sun Aug 26, 2012 8:16 pm

Hi all again, The gear set in the box is gearboxmans wide gear set, they supplied the oil they tell me to use. However I know having a gearbox sorted isn`t a cheap purchase and at over £1500 English I wouldn`t expect a whine resembling an old model T ready to drop its gearbox.
I have to assume the job has been done well and it may get a little quieter as it wears in especially if they are straight cut gears.
All I can do here is wait and see, however if this is an example of work well done then I am very worried about the standard of work I have paid for what I have ended up with, the box wasn`t this noisy when it went for repair!

mike-b · Post by **mike-b** » Sun Aug 26, 2012 9:21 pm

Hi Sidecar, They are the Quaife wide band gears, I expect some noise from new straight cut gears `till they wear in a bit, perhaps I`m wrong but the noise they make really does sound like a buggered gearbox.
Will do what you asked and post here what gearboxman has to say.

sidecar · Post by **sidecar** » Sun Aug 26, 2012 9:25 pm

I would have thought that the standard gears should not whine at all, please post up what Gearboxman say about this.

Post by **katanaman** » Sun Aug 26, 2012 10:51 pm

straight cut gears will always whine that's why they are only ever used in competition boxes. Road boxes use helical cut gears which don't whine but you loose more power through these gears.

mike-b · Post by **mike-b** » Sun Aug 26, 2012 11:44 pm

Hi Marki, Thanks for your last, Ok fair enough noise from straight cut, and yes I did notice the car seemed to have some more power.
You have probably hit the answer, all seem to say expect noise from straight cut, I just think it seems a lot! This is probably a costly mistake on my part, though it wasn`t pointed out to me that they would make so much noise and the answer to that is "Hard luck" live with it!

sidecar · Post by **sidecar** » Mon Aug 27, 2012 9:08 am

mike-b wrote:Hi Sidecar, They are the Quaife wide band gears, I expect some noise from new straight cut gears `till they wear in a bit, perhaps I`m wrong but the noise they make really does sound like a buggered gearbox.
Will do what you asked and post here what gearboxman has to say.

Aha, if they are cut the same way as mine then they must make the same noise as mine. GBM said that they are not straight cut but they are more straight than the originals.

As my box is in a Cobra replica with noisy sidepipes so I'm not too fussed about the whine but I can see how it would be annoying other types of car. Mine sounds like a Moggie Minor with a duff diff, GBM said that I should think of the whine more as a British touring car!

ChrisJC · Post by **ChrisJC** » Mon Aug 27, 2012 10:00 am

The other point about straight-cut vs helical is that helical put a side-load on the bearings as they are continually trying to push themselves out of mesh. But on the plus side, you have stronger gears because multiple teeth are meshing at the same time. With straight cut gears, you don't have any side-loads on the bearings, but you are only driving through one tooth at a time.

Double-helical gears on the other hand are the best of both worlds, as Andre Citroen knew (hence the logo)!

Chris.

mike-b · Post by **mike-b** » Mon Aug 27, 2012 1:28 pm

Hi All, It seems to me I`ve got to accept the noise of a whine, fair enough when it comes down to it I have no one to blame but myself - I should have known or checked first.
As my old man would have said "You made your bed - now lay on it".
As usual on this site you learn a lot .......... IF you ask first you learn not to do certain things. I am grateful to you all for the info provided, I`ve even learned where a Citroen badge comes from!
Sidecar, I will still put gearboxmans answer here on Tuesday.

Post by **katanaman** » Mon Aug 27, 2012 4:55 pm

Have a look at some in car footage of the WRC and make yourself feel better. They use pure straight cut gears and the noise of the box is all you can hear usually. Some would actually say it sounds good!

mike-b · Post by **mike-b** » Tue Aug 28, 2012 7:35 pm

Back again ...Had a word with CTS ( gearboxman ) today seems I have nothing to worry about, we confirmed I was using the correct oil 75W/90 semi synthetic from themselves.
Marki ..... Thanks for that ..... I feel a lot better now.

Cheers guys many thanks for all your help, Mike