Titan (sintered plate) oil

[CtrMint]

Hi, 

Having read various articles and posts on the forum and also the excellent guide here;

https://www.lotus7.club/guides/maintenance/bmw-differential-titan-limited-slip-unit-how-check-protect-while-service

I'm looking for confirmation regarding the correct oil for my new Titan.  The guide suggests  SAE 90 GL5 LS oil, however CC sent me 75W140 during my original build.

I'm about to order my new oil in readiness for the diff going into the 420R, so thought I'd double check.

Thanks

[David_Long]

Viscosity is really down to how you intend to use it, but the heavier grade, the better protection. I wouldn't get too concerned about the particular viscosity or the brand you use - it's probably more important to change it regularly. The trade off  of heavier grades is the power loss and possibly the noise that is generated. A modern GL5 gear oil that's LS 75w140 would be my choice for a road car. But a straight SAE 90 hypoid gear oil with an LS additive may be quietest.  For competition I use Redline shockproof heavy (rated at 75w240). For smooth LSD action (and the least chatter) use an LS oil.

[Geoff Brown]

As the author of 'the excellent guide' (thanks) the oil type mentioned is recommended by both Road & Race Transmissions & Tracsport . When enquiring about suitable oil with Steve Perks he concurred that an SAE 90 GL5 is OK as is any good LS multi grade.

Personally I filled my Tracsport diff with Castrol B373 SAE 90 GL5. It was a GL6 but has been downgraded to conform with current standards. 373 is a mineral oil so I intend to change it quite often. In fact it will be one year since diff refit with Tracsport LS unit so watch this space for details on oil sample & what may be found on the mag plug.

With 373 in it the diff is very quite with no chatter or any other noises one could associate with an LSD - especially a Titan. There is a slight wine at certain RPMs but this tends to fade as the diff warms up.

#1 CtrMint - Don't forget the Gold Mag Plug especially as you are fitting a Titan LSD - again ! 

 

[ScottR400D]

CC used to recommend a 90 or a 75/90. I believe they changed to the 75/140 when the Titan became the source of complaints. 

I've tried, over the past year/18 months, Redline 75/90, Redline 80/140 and the RRT 90 in both the Titan and the Tracsport LSD. I noticed no difference in the noises made by either LSD whichever oil was in there. 

As DL says the heavier oil leads to a small power loss Redline say 0.5%, 75/90 v 80/140 though at what temperature I'm not sure. 

The thing is our diffs, on the road, don't get particularly hot, IME. I measured the temperature after a 20 mile or so run with each oil. Steve Perks told me it would be around 70c and it always was. 

At 70/75c I wouldn't expect the viscosity of the 75/90 or 80/140 would be that much different, though I stand to be corrected.  
 

[Dan R]

I stumbled across this thread earlier regarding Diff oil, .... it may be of use in general ....

https://www.lotus7.club/forum/techtalk/differential-oil-and-lesson-learnt

 

 

[aerobod - near CYYC]

On track days the infrared thermometer shows my diff getting up to 100C in 30C ambient temps when measured immediately after returning to the pits, likely the oil is up around 120C or so around peak. I also sometimes drive the car in ambients down to -10C or so. With my wide operating temp range, synthetic 75W140 makes the most sense. I probably have one of the greatest temp ranges to contend with compared with any Caterham owner, though.

[CtrMint]

thanks all 

I'm surprised someone hasn't tried running something smiliar to the following to closely monitor the temps.

https://www.importcarparts.co.uk/parts-info?id=9425

[Geoff Brown]

#5 DanR - I had completely forgotten about that thread so it did not sway my use of B373 the performance of which I am more than happy with.

I may stand to be corrected but I believe that the multi grades have certain friction additives that make the LSD quite - less clunking & chatter - which historically may not work with a lot of Titans !

The use of which oil for what purpose is an informed, personal decision.