Trans-x Differential

[mmt 15]

In respect of oil choice.

 

Trans X reccomends Millers LSD oil on their web page. This oil will be good to the diff and make it work as intended.

 

LSD oil will wear the syncros faster than "normal" gearoil.

 

Either you take care of the syncros or you take care of the diff.

 

Millers now has an LSD oil with "NT" apperantly "nano tecnology". I spoke to one of their "oil-engeneers" and the addition of NT should make the oil take better care of the syncros(than normal LSD oil) while the diff will work perfectly. I´ve been using the NT oil this season and it works perfect. Don´t know for how long the syncros will hold out though.

 

Oil companies don´t develop much in this aera because most LSD´s is in their own separate casing.

[Galifrey 1]

http://www.tran-x.com/diffs/pbe.html

 

Shows recommended oils as MILLERS CRX LS 80W-90 or MILLERS CRX TRANS/ LS 80W-140 1204 'BM'

 

Certainly mine is whisper quiet when cold, but once warm it gets noisier indicating that the thinning of the oil at temperature is leading to the increased noise.

 

The question for me is which oil gives the best balance of Diff and Synchro life without making your car sound like it has a broken driveshaft when going through a low speed manouver

 

Just to note, what Opie say about 80-140

 

Generally 0.5% less efficient that 75W90. Can also be used in differentials and transmissions where excessive noise is a problem and limited-slip differentials which vibrate excessively when turning a corner.

Edited August 8, 2010 by Galifrey

[Anthony 1,003]

For what it's worth, I'm running my Tran-X on standard 75W80 Total BV (as specified for BE boxes) and it's as quiet as a mouse, with no banging, clunking or juddering whatsoever - and because it's the correct oil for the synchros, the shift is lovely and smooth too

[andyjstone 6]

Mine is terrible at slow speed, particularly when trying to pull away at anything other than straight on when it clunks and grinds and knocks, to the extent that I was about to take it out and send it back to TranX (it's already been back once).

 

However, I have been speaking to TranX and their last comment was: 'AS THE LSD UNIT BEDS IN THE PRELOAD WILL SETTLE DOWN AND ALLOW A LITTLE MORE SLIP IN THE PLATES. I HAVE A DOLOMITE SPRINT WITH ONE OF OUR UNITS IN AND IT DOES THE SAME THING AND HAS DONE FOR 12000 MILES NOW. IT CAN BE ALARMING BUT IT IS A CHARACTERISTIC OF A PLATE TYPE UNIT. YOU DO FEEL IT MORE AS ITS FWD BECAUSE IT COMES THROUGH THE STEERING WHEEL AS WELL. WHEN YOU SENT IT BACK BEFORE WE WOULD HAVE LOOKED IT OVER AND WE WOULD HAVE FRESHENED IT UP AND THE UNIT WOULD NEED TO BED IN AGAIN. IT CAN BE MANAGED BY USING DIFFERENT OILS LIKE AN 80W 140, BUT THIS IS DIFFICULT WITH FWD CARS AS THE GEARBOX TAKES PRIORITY AND THE OIL NEED TO SUIT THE GEARS RATHER THAN THE LSD.'

 

I'm currently using FUCHS TITAN SINTOFLUID SAE 75W-80, but I'm thinking of giving the MILLERS CRX LS 80W-90 or 80W-140 to see if it makes any difference.

[matt.f 16]

Mine didnt make any noise when i first put it in but after about 300 mile now makes a few groaning noises when pulling away on lock,car is miles better with it in though

[andyjstone 6]

Mine didnt make any noise when i first put it in but after about 300 mile now makes a few groaning noises when pulling away on lock,car is miles better with it in though

 

Is it a TranX and what oil are you using?

[matt.f 16]

Is it a TranX and what oil are you using?

Yea Tran-x,think it was Total said on the back reccomended for citroen/peugeot gearbox's

[Tom Fenton 1,542]

but I'm thinking of giving the MILLERS CRX LS 80W-90 or 80W-140 to see if it makes any difference.

 

If you do this you will find the shift horrible, even to the point of it not wanting to go in gears, especially when it is cold. You need to use 75/80 for the synchros to work, as Tranx correctly say.

 

My diff also makes some noise, these are after all designed primarily for competition use. If you want a quiet diff then a Quaife is the one, not ultimately as effective as the Tranx but much better mannered.

[matt.f 16]

^^^^^^Spot on

[Galifrey 1]

If you do this you will find the shift horrible, even to the point of it not wanting to go in gears, especially when it is cold. You need to use 75/80 for the synchros to work, as Tranx correctly say.

 

My diff also makes some noise, these are after all designed primarily for competition use. If you want a quiet diff then a Quaife is the one, not ultimately as effective as the Tranx but much better mannered.

 

5 viscosity rating really makes that much difference cold?

 

Funny thing is, mine is quiet as a mouse when cold, it's the warm viscosity that appears to be causing the noise, the difference between 80 and 140 in the warm performance ratings just means the oil thins less at temperature, it is not actually massively thicker at low temps, and at temperature, the oil will be thinner than a 75w oil when cold.

 

to explain:-

 

75w = will be no thicker viscosity than a 75 single viscosity oil at low temperature

80w = will be no thicker viscosity than a 80 single viscosity oil at low temperature

80 = will be no thinner than a 80 signle viscosity oil at high temperature

140 = will be no thinner than a 140 single viscosity oil at high temperature

 

In effect, the oil has modifiers that stop it thinning as much as the temperature gets higher, so in reality, the 80-140 higher rating oil will have more drag than a 75/80 at higher temperatures but will never be more viscous than an 80w oil at low temps.

 

Now of course I know very little about the impact of changing from 75-80 oil in a Pug box, and therein lies the crunch (pardon the pun).

 

The biggest issue with a plate diff, is that the oil in the gearbox reaches far higher temperatures than a normal diff due to the increased energy release due to the plates "slipping" when not fully locked.

 

The Millers oil is not recommended for Synchro boxes, so that is clearly not a good recommendation from Tran-X

 

Think I am gonna try the Total 75w-80 many seem to say it works well.

Edited August 16, 2010 by Galifrey

[Tom Fenton 1,542]

5 viscosity rating really makes that much difference cold?

 

yES SUPRISINGLY (oops caps sorry) it does. I found this out years ago when I put some 80W/90 in my old 306 diesel turbo, as I was skint and had the 80-90 kicking about.

 

From behaving itself, it would refuse to go into 1st gear, and generally be horrible until it had warmed through after a few miles use.

 

Swapped to the correct grade 75-80 and straight away it was how you would expect, no gear selection problems.

 

The clearances (I once explained this and said tolerances, and got shot with sh1t) between the synchro rings and cones are designed with the oil grade in mind.

[Galifrey 1]

Thanks Tom

 

although my car is likely being sold soon, would like to minimise the diff noise if possible as it may make potential buyers nervous.

[andyjstone 6]

Think I am gonna try the Total 75w-80 many seem to say it works well.

 

Is this going to make the diff any quieter than the Fuchs TITAN SINTOFLUID SAE 75W-80 I'm using now?

[matt.f 16]

Not sure about the Fuchs but mine is a bit groany at slow speed with Total,gearbox fine aswell.

[andyjstone 6]

Quick update on this - I changed my gear box oil from Fuchs TITAN SINTOFLUID SAE 75W-80 to Total Transmission BV 75w-80 and either it has suddenly bedded in or it has made a massive difference as the diff hardly makes any noise at all now, much better

[Anthony 1,003]

That's what I run Andy, and as per my reply earlier in the thread, my Tran-X is nigh-on silent and doesn't clunk, bang etc

[tri_longer 25]

Just had my Tran X in for a service, though turned into more of a re-build at £225.

 

I though that was bad until my mate removed his and some of the planet gears fell out when he removed it. His re-build has just cost best part of £500.

 

If in doubt I'd say get it checked, just in case.